Terry's Astronomy Thread.

[Myattboy]

Originally Posted by Bluearrowll

With a budget in that area, you enter a whole new field of view.

http://www.telescope.com/Orion-StarB...on%20StarBlast

Take a look at this telescope. It comes with a computer object finder which becomes functional after you align it with 2 very bright stars. Its database contains thousands of objects that you can punch in and the telescope will move to that specific spot in the sky that it should be in (provided it's been aligned correctly).

I am getting ready to leave for class now, and I need to prepare for my astronomy final exam tomorrow, and I can go into further detail if you want. But this is definitely one to take a look at. As an added bonus it's one of Skyandtelescope's hot products of 2010 (means it's very good.)

I suggest taking a look at the video gallery and customer reviews, they're quite helpful and sometimes customer reviews have photos taken with the product!

That sounds perfect! Definitely at the top of the list. Do you think it'll be good for taking long exposures as well?

Hope your exam went okay as well mate.

[Spenner]

As far as cameras go, the Canon 20Da, while I'm not sure WHERE to get it, is designed specifically for astrophotography, being that it doesn't filter out infrared light and will produce higher contrast and sharper photos.

http://en.wikipedia.org/wiki/Eos_20d#EOS_20Da

However apparently now there's a Canon 60Da which clearly would be more desirable for basically the same cost

http://en.wikipedia.org/wiki/Canon_EOS_60Da#EOS_60Da

Though these are quite pricey. What is your budget for the photographic end of this? With that telescope all you'll be needing is a body for the camera and either using it with a remote shutter, or simply plugging the camera into a laptop and doing it live.

EDIT: Woops, didn't read that you've already been doing astrophotography. Either way, some more info if your camera isn't up to par :P

[Bluearrowll]

What's in the Sky Tonight?
April 6, 2012

-Full Moon (exact at 3:19 p.m. EDT). This evening the Moon shines in the east with Spica a little to its left and Saturn farther left — a pretty lineup, as shown here. Farther to the Moon's right, look for the four-star pattern of Corvus, the Crow. Much farther to the upper left (outside the picture here) is bright Arcturus, the "Spring Star."

-Mars (magnitude –0.7) shines bright fire-orange under the belly of Leo. Regulus is 5° to Mars's right in the evening, and Gamma Leonis is 7° above it. Mars was at opposition on March 3rd. Now it's fading and shrinking as Earth pulls ahead of it along our faster, inside-track orbit around the Sun. But at least Mars is shining higher in the evening sky now. It's highest in the south by around 10 or 11 p.m. daylight-saving time.

Astro Picture of the Day:
April 6, 2012

Source:
After wandering about as far from the Sun on the sky as Venus can get, the brilliant evening star crossed paths with the Pleiades star cluster earlier this week. The beautiful conjunction was enjoyed by skygazers around the world. Taken on April 2, this celestial group photo captures the view from Portal, Arizona, USA. Also known as the Seven Sisters, even the brighter naked-eye Pleiades stars are seen to be much fainter than Venus. And while Venus and the sisters do look star-crossed, their spiky appearance is the diffraction pattern caused by multiple leaves in the aperture of the telephoto lens. The last similar conjunction of Venus and Pleiades occurred nearly 8 years ago. As it did then, Venus will again move on to cross paths with the disk of the Sun in June. It is the last time in our lifetime that it will do so. Unless you plan to live through the late 22nd century.

---------------

What's in the Sky Tonight Archive March 1, 2013 - July 31, 2013

July 31, 2013

-Find Altair again high in the southeast after dark. To its right, by about a fist and a half at arm's length, is the dim but distinctive little constellation Delphinus, the Dolphin, jumping leftward.

-Solar activity remains low. The only action on the Earthside of the sun is a minor crackling of C-class solar flares from departing sunspot AR1800. NOAA forecasters estimate a 10% chance of M-class flares and no more than a 1% chance of X-flares on July 31st.

July 30, 2013

-Bright Vega shines nearly overhead these evenings, for those of us at mid-northern latitudes. Look southeast for Altair, almost as bright. Above Altair by a finger-width at arm's length is its little orange sidekick Tarazed, 3rd magnitude.

-Earth is passing through a stream of debris from Comet 96P/Machholz, source of the annual Southern Delta Aquariid meteor shower. The shower's broad peak, centered on July 30th, is expected to produce a meteor every 4 or 5 minutes during the dark hours before local sunrise. Southern hemisphere observers are favored.

-On July 24th, about an hour after sunset, Gerardo Connon of Rio Grande city in Tierra del Fuego, Argentina, walked outside and witnessed a rare display of nacreous clouds. The colorful apparition was as bright as the street lights in the city. These clouds, also known as "mother of pearl clouds," form in the stratosphere far above the usual realm of weather. They are seldom seen, but when they are, the reports usually come from high-northern parts of our planet. This apparition over Tierra del Fuego was unusual indeed. Atmospheric optics expert Les Cowley explains the special conditions required to create such a cloud: "Take an unusually cold lower stratosphere (15-25km high), use some gravity waves generated by high winds and storms in the troposphere to stir in some water vapour, and - voilà! You get these clouds made of tiny ice crystals shining after sunset with unforgettably bright iridescent colors."

July 29, 2013

-Last-quarter Moon (exact at 1:43 p.m. EDT). The Moon rises around midnight tonight, shining below the stars of Aries. As it climbs higher through the morning hours, look well to its lower left for the Pleiades.

- A pair of CMEs launched into space on July 26th by erupting solar filaments will apparently miss Earth. The odds of a geomagnetic storm this weekend are low.

July 28, 2013

-Starry Scorpius is sometimes called "the Orion of Summer" for its brightness and its prominent red supergiant (Antares in the case of Scorpius, Betelgeuse for Orion). But Scorpius is a lot lower in the sky for those of us at mid-northern latitudes. This means it has only one really good evening month: July. Catch Scorpius due south just after dark now, before it starts to tilt lower toward the southwest.

-Jupiter is climbing higher above faint Mars low in the dawn. What morning can you first pick up Mercury?

-On Saturday, July 27th, the Russian Space Agency launched a Progress supply ship to the International Space Station. The Progress quickly caught up with the ISS and docked to the outpost, delivering food, fuel, and the last-minute addition of a repair kit for a U.S. spacesuit that malfunctioned during a spacewalk last week. Shortly before docking, Monika Landy-Gyebnar saw the two spaceships fly over her home in Veszprem, Hungary:

"The ISS appeared in the NW sky, glowing brightly," says Landy-Gyebnar. "About 10 seconds later I noticed a very faint dot of light following it - the Progress!"

"At the middle of its route across the sky, the Progress spacecraft produced a very bright flare, even brighter than ISS," she continues. "It was short, but very spectacular. At maximum, the flare's astronomical magntitude was about -5, while the ISS was only -2.5. Other observers from Hungary saw it, too." (The flare was caused by sunlight glinting from a flat surface on the spacecraft.)

"As the spaceships flew on towards the NE horizon, Progress became less and less bright and soon it faded into the sky background," she concludes. "The ISS remained bright until it set. Then I packed my gear and came home to watch the docking on NASA TV."

-Spaceweather can tell you when fly bys will happen in your area through here: http://spaceweather.com/flybys/

July 27, 2013

-During the late hours of July 26th, two filaments of magnetism erupted on the sun. The first to blow was this loop on the sun's southwestern limb. A second filament connecting sunspots AR1800 and AR1805 erupted shortly thereafter. The explosions hurled coronal mass ejections (CMEs) into space. One of them (the one propelled by the filament connecting AR1800 and AR1805) might be heading in the general direction of Earth. An analysis the CME's trajectory is in progress as more imagery becomes available.

-The students of Earth to Sky Calculus have recovered the petunias they sent to the stratosphere last Friday. The flowers left Earth July 19th onboard a helium research balloon, ascended to 110,570 feet, then parachuted back to Earth on the same day. The below four screenshots show the following scenarios:

(1) The flowers were pink and alert when they left Earth. (2) An hour later, in the stratosphere, the flowers appear limp and wilted, but they were not. Actually, the flowers were frozen. The petals were bent downward by onrushing wind during the ascent, and they froze in place as the petunias passed through the tropopause where the temperature was -63 C. (3) You can see that the flowers were frozen stiff because when the balloon exploded, they did not move at all. (4) Finally, as the payload parachuted back to Earth the flowers thawed and turned deep purple.

July 26, 2013

-The Delta Aquariid meteor shower should be in its broad maximum all week. This and other weak, long-lasting July showers with radiants in the southern sky increase the chance that any meteor you see will be flying out of the south.

-Mercury, Mars, and Jupiter shine low in the east-northeast during dawn. Jupiter is the highest and brightest (magnitude –1.9). Look for faint Mars (magnitude +1.6) a little to Jupiter's lower left. Look below them, and perhaps a bit left, for Mercury, which brightens from magnitude +1 to 0 this week. Best time: about 60 to 40 minutes before your local sunrise. Binoculars may help with the fainter two planets, especially through summer haze.

July 25, 2013

-The waning gibbous Moon rises due east late this evening. If you have a distant, flat eastern horizon, mark the spot. The Great Square of Pegasus stands on one corner well to the rising Moon's upper left.

-Solar Cycle 24 is shaping up to be the weakest solar cycle in more than 50 years. In 2009, a panel of forecasters led by NOAA and NASA predicted a below-average peak. Now that Solar Max has arrived, however, it is even weaker than they expected. It may be premature to declare Solar Cycle 24 underwhelming. Solar physicist Dean Pesnell of the Goddard Space Flight Center thinks Solar Cycle 24 is double peaked - and the second peak is yet to come. Also, weak solar cycles have been known to produce very strong flares. The strongest solar storm in recorded history, the Carrington Event of 1859, occurred during a relatively weak solar cycle like this one.

July 24, 2013

-The two brightest stars of summer evenings are Arcturus in the west now and Vega nearly overhead. They're 37 and 25 light-years away, respectively.

-Mars and Jupiter are low in the east-northeast during early dawn. Jupiter is by far the brightest at magnitude –1.9. Binoculars help with finding Mars, magnitude +1.6, right close by. Jupiter and Mars passed just 3/4° from each other on the morning of July 22nd.

July 23, 2013

-Look northwest after dark for the Big Dipper, hanging diagonally. Its handle is on the upper left. Follow the curve of the handle on around leftward, for a little more than a Dipper-length, to land on bright Arcturus in the west.

-Solar activity has shifted from low to very low. None of the sunspots on the Earthside of the sun are actively flaring. NOAA forecasters expect this situation to continue for the next 24 hours. They estimate a slim 10% chance of M-class flares and no more than a 1% chance of X-flares on July 23rd.

July 22, 2013

- Twinkly Regulus is now 1¼° below Venus at dusk.

-Full Moon (exact at 2:16 p.m. EDT). The Moon travels across the sky tonight in western Capricornus.

July 21, 2013

-As twilight fades away, spot Venus low in the west-northwest. Look 1¼° to its lower left for much fainter Regulus. Bring binoculars.

-Venus (magnitude –3.9) shines brightly low in the west-northwest during evening twilight. In a telescope it's still small (12 arcseconds) and gibbous (85% sunlit).

-Solar activity is low. The biggest sunspot on the Earthside of the sun, AR1783, has been quiet for days even though it has a 'beta-gamma' magnetic field that harbors energy for M-class solar flares. NOAA forecasters estimate a slim 10% chance that AR1783 will break the quiet with an M-flare on July 21st.

July 20, 2013

-Look upper left of the Moon after dusk, by roughly three fists at arm's length, for Altair, the bright eye of Aquila the Eagle. A little less far to the Moon's right is Antares, the fiery heart of Scorpius.

-Earth's "noctilucent daisy" is glowing brighter than ever. Seeded by meteor smoke, noctilucent clouds are surrounding the north pole in a luminous circle visible from ground and space alike. Tadas Janušonis photographed this display on July 18th from Vabalninkas in the Birzai district of Lithuania:

July 19, 2013

-Telescope users looking at the gibbous Moon from most of North America tonight can watch the Moon's invisible dark limb creep up to and occult the 4.4-magnitude star Xi Ophiuchi. Only Florida and the West miss out.

-Some times of the star's disappearance: in western Massachusetts, 12:38 a.m. EDT; Atlanta, 12:32 a.m. EDT; Chicago, 11:10 p.m. CDT; Winnipeg, 10:50 p.m. CDT; Kansas City, 11:00 p.m. CDT; Austin, 11:07 p.m. CDT; Denver, 9:39 p.m. MDT. Start watching early.

-Opening up like a zipper almost a million kilometers long, a vast coronal hole has appeared in the sun's northern hemisphere. Coronal holes are places in the sun's upper atmosphere where the magnetic field opens up and allows solar wind to escape. A broad stream of solar wind flowing from this particular coronal hole should reach Earth on July 19-20.

-In addition, NOAA forecasters say a CME could hit Earth's magnetic field late on July 18th. The combined impact of the CME and the incoming solar wind stream could cause some stormy space weather around Earth in the days ahead. NOAA forecasters estimate a 65% chance of polar geomagnetic storms on July 19-20.

July 18, 2013

-Look lower left of the gibbous Moon this evening for the red supergiant Antares. Also nearby are other stars of upper Scorpius.

-Noctilucent clouds are our planet's highest clouds - but exactly how high are they? The textbook answer is 82-82 km, but textbooks can be wrong. Peter Rosén of Stockholm, Sweden, decided to find out for himself. "On July 4th I photographed some interesting NLCs," he explains. "After uploading them on Spaceweather, I noticed that P-M Hedén had photographed the same formations and at the same time from a location 26 km (16 miles) north of mine. I decided to make precise measurements of the same features in both pictures with respect to the stars and try to determine the exact geographical position and height of these NLCs.Some years ago I found a very useful calculator put online by Paul Schlyter to measure the position and altitude of Perseid meteors. By entering the geographical position of both observers and the respective coordinates of an object in the sky, it will compute the position and altitude of the object. In this case, I used it for NLCs." He picked four features color-coded in the figure below and measured their positions. "The height of these NLCs ranged from 75.1 km (blue dot) to 78.6 km (red dot)," he says. "These results seem to be a little bit lower than the value of 83 km that is often referenced."

The calculator is found here: http://stjarnhimlen.se/calc/metnlcalt_en.html

July 17, 2013

-The Moon stands in central Libra this evening, about midway (for the longitudes of the Americas) between Saturn to its right and the stars of upper Scorpius to its left.

-Venus (magnitude –3.9) shines brightly low in the west-northwest in evening twilight. In a telescope it's still small (12 arcseconds) and gibbous (87% sunlit). But for the rest of the year, watch it grow in size and wane in phase until becoming a long, ultra-thin crescent.

July 16, 2013

-This evening the Moon shines below Saturn, with Spica now off to their lower right.

-Aisle or window? The next time you're making that decision at the airport, consider the following snapshot. "I was expecting auroras when I boarded Air Canada flight 854 from Vancouver to Heathrow on the evening of July 14th - and I was not disappointed," reports photographer Yuichi Takasaka. "Above the James Bay in the northern Manitoba, the lights grew so bright that I could see them through the twilight. Note the colors reflected from the wing of the plane, these were the strongest auroras I've seen from an airliner ever!" A 0.25 second exposure yielded this image:

-According to NOAA forecasters the odds of a polar geomagnetic storm on July 16th are 20%, increasing to 50% on July 18th when a solar wind stream is expected to hit Earth's magnetic field. Add to that the near-certainty of high-latitude noctilucent clouds and ... pick the window seat.

July 15, 2013

-First-quarter Moon (exact at 11:18 p.m. EDT). Look quite close to the Moon for Spica. Saturn glows off to their upper left. Think photo opportunity.

-The Moon occults (hides) Spica for skywatchers in Hawaii and parts of Central and South America. For Timetables: http://www.lunar-occultations.com/io...0716zc1925.htm

July 14, 2013

-Do you live too far north to see Alpha Centauri? The nearest star for northerners is Barnard's Star, a red dwarf 6.0 light-years away in northern Ophiuchus. At magnitude 9.6 it's fairly easy in most telescopes.

-Mars and Jupiter are low in the east-northeast during early dawn. Jupiter is far and away the brightest at magnitude –1.9. Look just upper right of it for Mars, magnitude +1.6. Binoculars help. Jupiter is drawing closer to Mars daily. They'll pass just 3/4° apart on the morning of July 22nd.

July 13, 2013

-Summery Scorpius struts in the south right after dark. Now is the time (before the Moon grows bright) to explore its Milky-Way-rich southern part, full of bright deep-sky objects. The northern part of Scorpius includes orange Antares and, to Antares's right, Delta Scorpii, a star that 13 years ago doubled in brightness and still rivals Antares for attention.

-Saturn is near eastern quadrature during July and August (90° east of the Sun), so this is when its globe casts the widest shadow onto the rings behind, as seen from Earth's viewpoint. That's the black band on the rings just off the globe at lower right of center (celestial northeast).
Meanwhile, the rings are now casting an almost equally prominent shadow onto the globe. That's the black rim above the rings (south here is up). Both add to Saturn's 3-D appearance in a telescope.

The gray band on the globe just inside the rings is the semitransparent C Ring, the sparse "Crepe Ring," with no shadow currently behind it to confuse its appearance.

Damian Peach shot this extraordinarily fine image through excellent seeing conditions on July 8th.

July 12, 2013

-The crescent Moon, faint Regulus, and bright Venus form a curving line low in the western twilight, as shown below.

-Not all colorful lights in the sky are the aurora borealis. The green light in the picture below is called "airglow." Airglow is a luminous bubble that surounds our entire planet, fringing the top of the atmosphere with aurora-like color. Although airglow resembles the aurora borealis, its underlying physics is different. Airglow is caused by an assortment of chemical reactions in the upper atmosphere driven mainly by solar ultraviolet radiation; auroras, on the other hand, are ignited by gusts of solar wind. Green airglow is best photographed from extremely dark sites on nights when the Moon is new or below the horizon. It often shows up in long exposures of the Milky Way: more airglow.Astrophotographer Kenneth Edwards discovered this for himself on July 4th when he was taking a long exposure of the Milky Way over Big Bend National Park, Texas:

July 11, 2013

-As twilight fades, spot the crescent Moon low in the west. Venus is roughly 1½ fist-widths at arm's length to its right (for North America). As dusk deepens, watch for Regulus and Gamma (γ) Leonis coming into view above them, as shown below.

-Despite its unstable magnetic field, big sunspot AR1785 has resisted exploding. Even so, it's putting on a good show. Pretty sunsets could give way to actual solar flares if the magnetic field of AR1785 finally erupts. For the 5th day in a row, flare probabilities remain high: NOAA forecasters estimate a 55% chance of M-flares and a 10% chance of X-flares. Pete Lawrence of Selsey UK photographed the active region as a dark-mark in the sunset on July 9th:

July 10, 2013

-Soon after sunset while the sky is still bright, watch for the thin crescent Moon coming into view just above the west horizon, to the lower left of Venus. Binoculars help.

-A minor CME hit Earth's magnetic field on July 9th at approximately 20:30 UT. The impact was weak, and at first had little effect, but now a geomagnetic storm is in progress as Earth passes through the wake of the CME

July 9, 2013

-If you have a dark enough sky, the Milky Way forms a magnificent arch high across the eastern sky after nightfall. It runs all the way from below Cassiopeia in the north-northeast, up and across Cygnus and the Summer Triangle in the east, and down past the spout of the Sagittarius Teapot in the south.

-Astrophotographer Thierry Legault is known for his razor-sharp images of spacecraft. Yesterday, for a change of pace, he photographed a razor-sharp crescent.

"This image shows the tiny lunar crescent at the precise moment of the New Moon, in full daylight at 7h14min UTC on July 8 2013," says Legault. "It is the youngest possible crescent, the age of the Moon at this instant being exactly zero."

"From the shooting site in Elancourt, France, the angular separation between the Moon and the Sun was only 4.4° (nine solar diameters)," he continues. "At this very small separation, the crescent is extremely thin (a few arc seconds at maximum) and, above all, it is drowned in the solar glare, the blue sky being about 400 times brighter than the crescent itself in infrared and probably more than 1000 times brighter in visible light. In order to reduce the glare, the images have been taken at near-infrared wavelengths using a pierced screen placed just in front of the telescope to block direct sunlight."

July 8, 2013

-This is the time of year when, as twilight fades to dark, the two brightest summer stars, Arcturus and Vega, shine equally close to the zenith (depending on where you are). Arcturus is the one toward the southwest; Vega is toward the east.

-New Moon (exact at 3:14 a.m. on this date EDT).

Colossal sunspot AR1785 is now directly facing Earth. The active region has a 'beta-gamma-delta' magnetic field that harbors energy for X-class flares, yet so far the sunspot has been mostly quiet. Could it be the calm before the storm? NOAA forecasters estimate a 55% chance of M-flares and a 10% chance of X-flares on July 8th. Solar flare alerts: text, voice.

Sprawling more than 11 Earth-diameters from end to end, AR1785 is one of the biggest sunspots of the current solar cycle. Christian Viladrich of Nattages, France, used a filtered 14-inch Celestron telescope to take this picture. All those irregular blobs surrounding the primary dark core are boiling granules of plasma as small as the state of California or Texas.

July 7, 2013

-When the stars begin to come out these evenings, the Big Dipper hangs straight down from its handle high in the northwest, while the dim, elusive Little Dipper stands straight up on its handle from Polaris in the north.

-When Opportunity left Earth on July 7, 2003, many observers expected the rover to survive no more than a few months on the hostile surface of Mars. Ten years later, Opportunity is still going strong and could be poised to make its biggest discoveries yet at a place named Solander Point.

-Behemoth sunspot AR1785 is undergoing a metamorphasis, changing shape by the hour as it turns toward Earth. In less than 24 hours, AR1785 has stretched and lengthened by more than 40,000 km. It is now more than 11 times as wide as Earth, which makes the active region an easy target for backyard. This movie from NASA's Solar Dynamics Observatory shows the action on July 6-7:

July 6, 2013

-Two hours after sunset, after darkness is truly complete, the east-northeast horizon bisects the Great Square of Pegasus across two of its opposite corners. By midnight the whole Great Square is up in good view, balancing on its bottom corner.

-Observers of noctilucent clouds often describe their appearance as "electric blue." The pale blue colors of the two phenomena are similar, but the resemblance is superficial. Lightning is hot, a genuinely electric discharge that heats the air to 30,000o C or more. The high temperature of the lightning's plasma (ionized air) gives it the same blue color as a hot O-type star. On the other hand, noctilucent clouds are cold, made of ice that crystallizes at the edge of space where the air temperature is -160o C. The tiny ice crystals in noctilucent clouds scatter blue light from the setting sun, which accounts for their lightning-like color. On July 3rd, Nature provided a color-check when a lightning storm erupted in Szubin, Poland, right in front of a noctilucent display. Marek Nikodem photographed the ensemble:

July 5, 2013

-During dawn this morning and Saturday morning, look low in the east-northeast for the waning Moon. It guides your way to Mars, Jupiter, Aldebaran, and Beta Tauri, as shown at right. Binoculars will help.

-Earth is at aphelion, its farthest from the Sun for the year (just 1 part in 30 farther than at perihelion in January).

July 4, 2013

-Watching the fireworks tonight? As you're waiting for them to begin, point out to people some sky sights. The two brightest stars of summer, Vega and Arcturus, are high overhead toward the east and southwest, respectively. Far below Arcturus are the planet Saturn and, to its lower right, Spica. Nearly that high in the southeast is the orange-red supergiant Antares, amid fainter stars of upper Scorpius.

-The July waning crescent Moon passes landmarks of Taurus. The visibility of faint objects in twilight is exaggerated here; binoculars help. The blue 10° scale is about the width of your fist at arm's length.

July 3, 2013

-A twilight challenge: As twilight fades, spot Venus low in the west-northwest. As darkness deepens, can you make out stars of the Beehive Cluster within about ½° below it? Good luck — the brightest of them are 6th magnitude, about 10,000 times fainter than Venus!

-A much easier challenge: Look ½° above Saturn soon after dark for the 4.2-magnitude star Kappa Virginis.

July 2, 2013

-The Big Dipper, high in the northwest after dark, is turning around to "scoop up water" through the nights of summer and early fall.

-The "noctilucent daisy" continues to expand and intensify as summer unfolds. Observers in central-to-northern Europe are reporting vivid, nightly displays of NLCs. Just hours ago, Alan Tough photographed these over Lossiemouth, Moray, Scotland.

"This was another spectacular display of noctilucent clouds," says Tough. "I arrived in Lossiemouth in time to see the Moon rising and managed to capture its glitter path on the River Lossie."

July 1, 2013

-If you have a dark enough sky, the Milky Way now forms a magnificent arch high across the whole eastern sky after nightfall is complete. It runs all the way from below Cassiopeia low in the north-northeast, up and across Cygnus and the Summer Triangle in the east, and down past the spout of the Sagittarius Teapot in the south-southeast.

June 30, 2013

-Vega is the brightest star high in the east. Right next to Vega lies one of the best-known multiple stars in the sky: 4th-magnitude Epsilon (ε) Lyrae, the Double-Double. It forms one corner of a roughly equilateral triangle with Vega and Zeta (ζ) Lyrae. The triangle is less than 2° on a side. A 4-inch telescope at 100× or more should resolve each of Epsilon's two wide components into a tight pair.
Zeta Lyrae is also a double star for binoculars; much tougher, but easily split with a telescope.

-As the current spate of geomagnetic storming subsides, more storms could be in the offing. A coronal mass ejection (CME), pictured below, is expected to deliver a glancing blow to Earth's magnetic field late on June 30th or early on July 31st.

-The cloud was propelled in our direction during the early hours of June 28th when magnetic filaments around sunspot AR1777 erupted. The explosion registered approximately C4 on the Richter Scale of Solar Flares. Because the CME is not heading squarely toward Earth, there is still a chance that it will miss.

For understanding the RIchter Scale of Solar Flares: http://www.spaceweather.com/glossary...8s4qc6tuni8p14

June 29, 2013

-This is the time of year when, after dark, the dim Little Dipper floats straight upward from Polaris (the end of its handle) — like a helium balloon on a string escaped from some summer evening party.

-Mercury is lost in the glare of the Sun.

A strong (Kp=7) geomagnetic storm is in progress on June 28-29 as Earth passes through a region of south-pointing magnetism in the solar wind. The storm has sparked Northern Lights photographed in the USA as far south as Kansas. Christian Begeman sends this picture from a farm outside Hartford, South Dakota:

"A clear sky allowed me to the Northern Lights dancing in southeast South Dakota around the midnight hour tonight," says Begeman. "It was quite the show."

High-latitude sky watchers should remain alert for auroras in the hours ahead. Solar wind conditions continue to favor geomagnetic activity.

June 28, 2013

-Southern hemisphere sunspots AR1777 and AR1778 erupted in quick succession during the early hours of June 28th, producing a pair of C-class solar flares and at least one CME. An initial analysis of coronagraph images suggests that the CME could deliver a glancing blow to Earth's magnetic field over the weekend.

-The Big Dipper, still high in the northwest, is moving a little lower now and starting to dip around toward the right. Follow the curve of its tail a little more than a Dipper-length left to bright Arcturus high in the southwest.

June 27, 2013

-Venus (magnitude –3.8) is gaining altitude very gradually, low in the west-northwest in evening twilight. Use binoculars to pick up Pollux and Castor off to its upper right or right.

-Mars and Jupiter remain hidden in the glare of the Sun.

-Every day, NASA's AIM spacecraft maps the distribution of noctilucent clouds (NLCs) around Earth's north pole. The results are displayed on spaceweather.com in the form of the "daily daisy." On June 20th, pilot Brian Whittaker flew past a vivid display of NLCs over the North Atlantic Ocean and he decided to compare his own view to that of AIM.

-"Once again, AIM's daily daisy-wheel allowed me to see where the northern horizon noctilucent clouds truly were!" says Whittaker. "This display reached a maximum height of about 10 degrees as seen from 37,000 feet at 50N latitude. It was my 4th and best sighting of 2013 so far."

-2013 is shaping up to be a good year for NLCs. The clouds surprised researchers by appearing early this year, and many bright displays have already been recorded. Once confined to the Arctic, NLCs have been sighted in recent years as far south as Utah, Colorado, and Nebraska. They might spread even farther south in 2013.

-Observing tips: Look west 30 to 60 minutes after sunset when the sun has dipped 6o to 16o below the horizon. If you see luminous blue-white tendrils spreading across the sky, you've probably spotted a noctilucent cloud.

-Here are the results:

June 26, 2013

-Now that it's summer, the Summer Triangle stands high in full glory after dusk. Its top star is bright Vega high in the east. Deneb is the brightest star to Vega's lower left. Farther to Vega's lower right is Altair. The Summer Triangle is big: 35° long. Where the sky is dark, you can see that the Milky Way runs through it.

-Solar activity is low. None of the sunspots on the Earthside of the sun has the kind of complex magnetic field that harbors energy for strong flares. NOAA forecasters put the odds of an M-class solar flare at 20% on June 26th, waning to 10% on June 27th.

June 25, 2013

-10,000 near-Earth asteroids and comets have now been discovered. The 10,000th object, asteroid 2013 MZ5, was detected on June 18th by the Pan-STARRS-1 telescope in Maui. Sobering estimate: NASA says there may be 10 times this number yet to find.

-During bright twilight today and tomorrow, Venus forms an almost straight line with Pollux and Castor low in the west-northwest. Bring binoculars, and look for them to Venus's right. And can you still detect Mercury below Venus? It's nearly as far below Venus (6°) as Pollux is to the right.

June 24, 2013

-Look a third of the way from Arcturus to Vega for dim Corona Borealis, the semicircular Northern Crown. It has one moderately bright star, Alphecca (magnitude 2.2). Look two thirds of the way for the dim Keystone of Hercules, whose brightest star is magnitude 2.8.

June 23, 2013

-This is the time of year when the two brightest stars of summer, Arcturus and Vega, are about equally high overhead shortly after dark. Arcturus is toward the southwest, Vega toward the east.

-Arcturus and Vega are 37 and 25 light-years away, respectively, and represent the two commonest types of naked-eye stars: a yellow-orange K giant and a white A main-sequence star. They're 150 and 50 times brighter than the Sun — which, combined with their nearness, is why they dominate the evening sky.

-Mercury is becoming a real challenge, rapidly fading and dropping below Venus very low in bright twilight. Bring binoculars. What's the last day you can keep it in view?

June 22, 2013

-The largest full Moon of 2013 rises around sunset and shines all night. Tomorrow night it's almost as full and almost as large (for the longitudes of the Americas, since the Moon is exactly full at 7:32 a.m. Sunday morning EDT.) On both nights, though, this "supermoon" is only a trace larger than an average Moon: 7% wider.

-On June 21st at 03:16 UT, the sun itself marked the solstice with an M2-class solar flare from sunspot AR1777. NASA's Solar Dynamics Observatory photographed the extreme ultraviolet flash and a plume of material flying out of the blast site. As sunspots go, AR1777 is neither large nor apparently menacing, yet it has been crackling with flares for days. Before it rotated over the sun's eastern limb on June 20th, it unleashed a series of farside flares and CMEs. Today's explosion was not Earth directed, but future explosions could be as the sun's rotation continues to turn AR1777 toward our planet. NOAA forecasters estimate a 30% chance of M-flares and a 5% chance of X-flares during the next 24 hours.

June 21, 2013

-As Mercury fades and descends below Venus day by day, how long can you keep it in view?

-After dark, look for fire-colored Antares to the lower right of the bright Moon.

June 20, 2013

-Look lower left of the Moon at dusk, by almost two fists at arm's lengths, for orange-red Antares. Between them is the three-star row of the Head of Scorpius, nearly vertical.

-This is Midsummer's Night, the shortest night of the year in the Northern Hemisphere. The solstice is at 1:04 a.m. on the 21st EDT; 10:04 p.m. on the 20th PDT.

June 19, 2013

-Dim little Mercury is closest to bright Venus low in twilight this evening. Look for it 2° to Venus's lower left.

-Saturn glows to the upper right of the waxing gibbous Moon as night falls.

June 18, 2013

-The magnetic field of sunspot AR1775 is growing more complex, increasing the chance of an eruption. NOAA forecasters estimate a 20% chance of M-class solar flares on June 19th.

-During the early hours of June 18th, a long-duration flare from this active region hurled a coronal mass ejection (CME) over the sun's eastern limb. However, none of the rocky planets (Mercury, Venus, Earth, Mars) were in the line of fire.

-The Moon now shines just below the line between Spica and Saturn.

June 17, 2013

-The Moon this evening forms the end of a curving line with Spica and Saturn, counting to the Moon's left. Look below the Moon for the four-star figure of Corvus.

-Watch the gibbous Moon pass Spica and Saturn. The Moons here are plotted for the middle of North America. They are three times actual size.

June 16, 2013

-First-quarter Moon (exact at 1:24 p.m. EDT). The Moon shines under the dim head of Virgo.

-Venus (magnitude – 3.8) is gaining altitude very gradually, low in evening twilight. Look for it in the west-northwest. Mercury has closed to just 2° or 3° from Venus, but Mercury is fading fast: from magnitude +0.6 on the 15th to +1.6 on the 22nd. Look for it to Venus's upper left (for mid-northern observers) early in the week, directly left around June 16th and 17th, and below Venus by the 20th.

June 15, 2013

-Mercury is drawing closer to Venus as it fades in the twilight, as shown below. They're 3.3° apart now and will be 2° from each other at their closest on the 19th.

June 14, 2013

-The waxing crescent Moon hangs to the lower left of Regulus and the Sickle of Leo this evening.

-If you've been looking for Jupiter, stop. The glare could hurt your eyes. Jupiter is approaching the sun for an extremely tight conjunction. Today they are only 3.5 degrees apart. On June 19th, Jupiter will pass directly behind the solar disk, less than a quarter of a degree from disk center. It's a rare total eclipse of Jupiter by the sun. Because of the glare, the event is invisible to human eyes. Coronagraphs, however, block the glare and monitor Jupiter's approach.

June 13, 2013

-Look above the Moon after nightfall to spot Regulus and the Sickle of Leo.

-Saturn (magnitude +0.4, in Libra) glows in the south during evening, with Spica 12° to its right. Look almost as far to Saturn's left or lower left for Alpha Librae.

-In a telescope, Saturn's rings are tilted 17° from our line of sight.

-The sunspot number may be low, but the sun is far from blank. Amateur astronomers monitoring the sun report a large number of magnetic filaments snaking across the solar disk. Sergio Castillo captured more than half a dozen in this picture he sends from his backyard observatory in Inglewood, California:

June 12, 2013

-The interesting binocular field around Antares holds the dim glow of the globular cluster M4, as many skywatchers well know. But do you also know about Rho Ophiuchi, the fine binocular triple star in the same field? It's the top of a loop of five stars including Antares.

-Mercury and Venus remain in twilight view low in the west-northwest, but Mercury is fading: from magnitude +0.2 to +0.8 from June 7th to 14th. Mercury is upper left of much brighter Venus, magnitude –3.8. Their separation closes from 5° to 3.6° during this time. Above them shine fainter Castor and Pollux.

June 11, 2013

-The waxing Moon after sunset now forms a wide arc with Castor, Pollux, and low Procyon, as shown at right. Venus and Mercury are not far from the center of the arc's curve.

-Early Wednesday morning, the faint asteroid 332 Siri will will occult (hide) a 6.4-magnitude star east of Antares for up to 4 seconds as seen along a track from Oklahoma across northwest Texas, southern New Mexico, and southern Arizona. The star is an unusually bright one to be occulted by an asteroid, but the event happens low in the southwestern sky. Details: http://www.asteroidoccultation.com/2..._332_29849.htm

June 10, 2013

-The thin crescent Moon low in twilight now forms a triangle with Venus and Mercury, as shown at right. Look above the triangle for the Pollux-and-Castor pair.

-NOAA forecasters have downgraded the chance of polar geomagnetic storms today to 25%. A CME expected to deliver a glancing blow to Earth's magnetic field on June 9th did not arrive on time and might have missed our planet altogether.

-Sky watchers in North America might see an outburst of meteors during the early hours of June 11th when Earth passes through a stream of cometary debris last seen in 1930. Forecasters Peter Jenniskens (SETI Institute) and Esko Lyytinen (Helsinki, Finland) predict the return of the gamma Delphinid meteor shower this Tuesday morning around 08:30 UT (04:30 am EDT). The shower is expected to last no more than about 30 minutes with an unknown number of bright, fast meteors. Bill Cooke of NASA's Meteoroid Environment Office will chat about the shower starting tonight at 11 PM EDT. Link: http://www.nasa.gov/connect/chat/gamma_chat.html

June 9, 2013

-After sunset, look for the young crescent Moon about 6° to 8° below Venus very low in the west-northwest (at the times of twilight in North America). Binoculars will help.

-NOAA estimates a 60% chance of polar geomagnetic storms on June 9th when a CME is expected to deliver a glancing blow to Earth's magnetic field. High-latitude sky watchers should be alert for auroras.

-High latitude sky watchers should be alert for NLCs in the evenings ahead. In recent years they have been sighted as far south as Utah, Colorado, and Nebraska. Observing tips: Look west 30 to 60 minutes after sunset when the sun has dipped 6o to 16o below the horizon. If you see luminous blue-white tendrils spreading across the sky, you've probably spotted a noctilucent cloud.

June 8, 2013

-After dark, look southeast for orange-red Antares. It's one of the two great red supergiants of the naked-eye sky; the other is Betelgeuse in winter. Around and to the upper right of Antares are other, white stars of upper Scorpius.

-This morning marks day 2 of the peak of the Arietids. The best way to observe the Arietids is via radar. Listen to their echoes on Space Weather Radio. http://spaceweatherradio.com/

-New Moon (exact at 3:14 a.m. on this date EDT).

June 7, 2013

-This week, Earth is passing through a stream of debris from asteroid Icarus, source of the annual Arietid meteor shower. The strange thing about this shower is that it occurs mainly during daylight hours. At its peak on June 7-8, as many as 60 Arietids per hour will streak invisibly across the blue sky after sunrise. The best way to observe the Arietids is via radar. Listen to their echoes on Space Weather Radio. http://spaceweatherradio.com/

-Mercury in the twilight has reached its farthest distance above Venus, 5°. See the scene below. They're as far apart as fainter Pollux and Castor above them, which come into view as twilight dims. 5° is about three finger-widths at arm's length.

June 6, 2013

-With June well under way, the Big Dipper has swung around to hang down by its handle high in the northwest after dark. The middle star of its handle is Mizar, with tiny little Alcor right next to it. On which side of Mizar should you look for Alcor? As always, on the side exactly toward Vega! Which is now shining in the east.

June 5, 2013

-Vega is the brightest star in the east these evenings. The main part of its little constellation, Lyra, dangles from it to its lower right.

-Jupiter is now all but out of view and only Venus and Mercury remain in the evening planet dance. However, Pollux and Castor will soon be joining them.

June 4, 2013

-Above the Big Dipper's high handle is north-central Bootes, home to double stars, three spindle galaxies, and the Kangaroo asterism.

-By June 5th the line of Venus, Mercury and Jupiter is 13° long with Jupiter falling far away.

June 3, 2013

-"Cassiopeia" usually means "Cold!". Late fall and winter are when this landmark constellation is high overhead (seen from mid-northern latitudes), but even on hot June evenings it's lurking low. After dark, look for it down near the north horizon. It's a wide, upright W. The farther north you are the higher it'll appear. But even as far south as San Diego and Atlanta it's completely above the horizon.

-Mercury, Venus, and Jupiter are still visible in the afterglow of sunset, forming a straight line pointing downward just above the west-northwest horizon as shown at the top of this page. Venus is the brightest. Jupiter, the bottom one, becomes harder to see each day and is gone by the end of the week. Mercury on top is having its best evening appearance of 2013.

June 2, 2013

-The best time to view Venus in a telescope is in late afternoon well before sunset, when it's still at a high altitude in relatively steady air. Mercury and Jupiter are in the same vicinity, but they're tougher catches in broad daylight.

-Mercury, Venus, and Jupiter are still visible in the afterglow of sunset, forming a straight line pointing downward just above the west-northwest horizon as shown at the top of this page. Venus is the brightest. Jupiter, the bottom one, becomes harder to see each day and is gone by the end of the week. Mercury on top is having its best evening appearance of 2013.

June 1, 2013

-Vega, shining brightly in the east-northeast, it currently the top star of the huge Summer Triangle. Look to Vega's lower left, by two or three fists at arm's length, for Deneb. The third star of the Summer Triangle is Altair, considerably farther to Vega's lower right. Altair is barely rising in the east as dusk fades away this week. How early in the evening can you spot it?

-At this time of year, right as the stars come out, the bright constellation Cassiopeia is directly underneath Polaris.

May 31, 2013

-Mercury, Venus, and Jupiter have stretched out into a nice straight line 7° long. Look low in the northwest after sunset. The line will continue to lengthen day by day, as Jupiter descends to the horizon and Mercury pulls a bit higher above Venus.

-Last-quarter Moon (exact at 2:58 p.m. EDT).

May 30, 2013

-Vega is the brightest star in the east-northeast these evenings. The main part of its little constellation, Lyra, hangs from it to its lower right.

-The bright planets in these scenes are plain to the naked eye, but the fainter stars may be hard or impossible to see in bright twilight. The scenes are about three fist-widths at arm's length wide. They're drawn for the middle of North America but will be good enough throughout the world's mid-northern latitudes. Today the planet trio forms a line.

May 29, 2013

-Here it is not even June yet, and the Big Dipper after dusk is already turning around to hang down by its handle. Look for it high in the northwest.

-The planet dance is on its way to form a line tonight. Venus and Jupiter are vertically aligned depending on your point of view.

May 28, 2013

-Jupiter and Venus are now at their closest together, 1° apart low in the west-northwest after sunset. Mercury is above them.

-Mercury, Venus, and Jupiter are bunched together low in the afterglow of sunset, forming a new configuration each evening. They're magnitudes –1, –4, and –2, respectively. From the 24th through 29th the three form a "trio," fitting in a circle 5° in diameter. They're bunched most tightly, fitting in a 2½° circle, on the evening of the 26th.

May 27, 2013

-This is the time of year when Spica, the brightest star of Virgo, shines due south just after dark. It's far to the lower right of high, bright Arcturus. Its name means "ear of wheat," and the Virgo stick figure is holding it in her hand without paying much attention. To Spica's lower right (by about a fist and a half at arm's length) is the four-star pattern of Corvus the Crow, eyeing it greedily. This year Corvus has Saturn to try to steal too. Saturn is glowing to Spica's left, noticeably brighter.

-Mercury, Venus, and Jupiter are bunched together low in the afterglow of sunset, forming a new configuration each evening. They're magnitudes –1, –4, and –2, respectively. From the 24th through 29th the three form a "trio," fitting in a circle 5° in diameter. They're bunched most tightly, fitting in a 2½° circle, on the evening of the 26th.

May 26, 2013

-Mercury, Venus, and Jupiter are bunched their tightest this evening, forming a little triangle just 2° on a side. Look in the northwest 30 or 40 minutes after sunset. Think photo opportunity.

-The best time to view Venus at high power in a telescope is in late afternoon well before sunset, when it's still at a high altitude in relatively steady air. All week Mercury and Jupiter are in the same vicinity, but they're tougher catches in broad daylight.

-Mercury, Venus, and Jupiter are bunched together low in the afterglow of sunset, forming a new configuration each evening. They're magnitudes –1, –4, and –2, respectively. From the 24th through 29th the three form a "trio," fitting in a circle 5° in diameter. They're bunched most tightly, fitting in a 2½° circle, on the evening of the 26th.

-Mercury and Venus appear closest together, just under 1½° apart, on the 23rd and 24th. Venus and Jupiter are closest, 1° apart, on the 28th.

May 25, 2013

-The Jupiter-Venus-Mercury trio continues shrinking. Above it, by contrast, the enormous Arch of Spring spans much of the western sky as twilight dims. Its highest part is the Pollux-and-Castor pair, roughly horizontal and about three finger-widths apart. Look far to the lower left of Pollux and Castor for Procyon, and farther to their lower right for Menkalinen and then bright Capella. Consult the video below for the planet dance.

May 24, 2013

-Jupiter, Venus, and Mercury, low in the afterglow of sunset, are now officially a "trio": they fit within a 5° circle. The means you could just about cover them with a golf ball at arm's length, and they'll fit in the view of most binoculars. They'll stay at least this close through next Wednesday the 29th. This evening, Venus and Mercury appear their closest together.

Full Moon (exact at 12:25 p.m. EDT tonight). The Moon is only two days from perigee, so it appears a tiny trace bigger than average.

The dazzling Moon occults (covers) the 2nd-magnitude star Beta Scorpii this evening for much of the eastern U.S. except the Northeast.

May 23, 2013

-Starting from Saturn in the south-southeast as evening grows late, follow a diagonal line of five objects toward the lower left: Saturn, fainter Alpha Librae, the glaring Moon, Delta Scorpii, and Antares.

-Saturn (magnitude +0.2, in Libra) glows in the southeast during twilight, with Spica to its upper right and Arcturus twice as far to its upper left. It's highest in the south not long after dark.

May 22, 2013

-Tonight the Moon shines with Saturn. Although they look close together, the Moon is only 1.3 light-seconds from Earth while Saturn is 74 light-minutes in the background.

May 21, 2013

-The star near the waxing gibbous Moon this evening is Spica in Virgo.

-Venus (magnitude –3.9) is still quite low in the west-northwest in twilight, to the lower right of Jupiter. Watch as Venus and Jupiter draw together by about 1° per day. On May 17th they're still 11° apart. Their conjunction comes on the 28th, when they'll be 1° apart with Mercury right alongside.

May 20, 2013

-Low in the afterglow of sunset, Jupiter has drawn to within 8° of Venus, which shines to its lower right. Can you see Mercury yet, 3° to the lower right of Venus?

-These three planets about to swing through a "trio" together, as shown in the video below. They'll appear closest together in a tight little triangle, 2° on a side, next Sunday the 26th.

May 19, 2013

-This is the time of year when the longest of the 88 constellations, mostly-dim Hydra, snakes level after dark all way across the sky from its head in the west (between Regulus and Procyon) to its tail-tip in the southeast (under Saturn).

May 18, 2013

-Saturn (magnitude +0.2, in Libra) glows in the southeast in twilight. Spica is to its upper right, and Arcturus is twice as far to its upper left.

-Saturn is highest in the south around 11 p.m. or so. In a telescope, its rings are nicely tilted 18° from our line of sight.

-Yes, it is a polar hexagon! The Voyager 2 spacecraft first revealed its shape, but now that Saturn's north polar region has come into Saturnian summer sunlight, amateur Damian Peach recorded the shape of the Hexagon as clear as day from Earth in this image taken on April 21, 2013, and re-projected as this pole-on view.

May 17, 2013

-By about 10 p.m. daylight saving time this week (depending on where you live), summery Antares becomes visible very low in the southeast with other stars of Scorpius around it.

-Find Antares about three fists at arm's length to the lower left of Saturn. Along the way you'll pass fainter Alpha Librae (not far from Saturn), and not-so-faint Delta Scorpii (relatively close to Antares).

May 16, 2013

-Just after nightfall at this time of year, Vega rising in the northeast is at the same altitude as Capella descending in the west. How accurately can you time this event? The time depends on your location, and wherever you are, it happens four minutes earlier each day

May 15, 2013

- Chi (χ) Cygni, one of the brightest red long-period variable stars, is having an unusually bright maximum. For the last two weeks it's been about magnitude 3.8, very plain to the naked eye. Look for it adding to the bottom part of the shaft of the Northern Cross, between Eta (η) and Beta (β) Cygni. Cygnus is reasonably well up in the east by about 11 p.m., with the Northern Cross lying on its side.

May 14, 2013

-Arcturus, high in the southeast, is sometimes called the "Spring Star," and Vega low in the northeast is called the "Summer Star." Look a third of the way from Arcturus down to Vega for the dim semicircle of Corona Borealis, the Northern Crown, with its one brightish star Alphecca. Look two thirds of the way for the dim Keystone of Hercules.

May 13, 2013

-Three zero-magnitude stars shine after dark in May: Arcturus high in the southeast, Vega much lower in the northeast, and Capella in the northwest. They appear so bright because each is at least 60 times as luminous as the Sun, and they are all relatively nearby: 37, 25, and 42 light-years from us, respectively.

May 12, 2013

-Jupiter and the 3-day-old Moon shine in the west at dusk, as shown below. Look for Betelgeuse still twinkling to their left.

-Saturn (magnitude +0.2, in Libra) is two weeks past opposition and climbing higher in the evening sky. It glows low in the southeast after nightfall (lower left of Spica and farther lower right of Arcturus), and is highest in the south around midnight. Stay up late with your scope.

May 11, 2013

-The beautiful 2-day-old crescent Moon hangs below Jupiter in the western evening twilight, as shown above. Look below the Moon for twinkly Aldebaran on its way out for the year.

-Venus (magnitude –3.9) is beginning an evening apparition that will continue the rest of this year. Can you pick it up yet? Look about 20 minutes after sunset just above the west-northwest horizon (well to the lower right of Jupiter as seen from mid-northern latitudes).

-And watch as Venus and Jupiter draw together this month, by 1° per day. They're 18° apart on May 10th and 11° on the 17th. Their conjunction comes on the 28th, when they'll be a close, 1° couple — with Mercury right alongside.

May 10, 2013

-Young Moon challenge. Have you ever seen a crescent Moon as young as about 24 hours? Not many people have, and in North America, now's your chance. Look just above the west-northwest horizon starting 15 minutes after sunset. The Moon is way down there close to Venus. Binoculars help, then try with your naked eyes.

-Note the time, then determine how long this is since new Moon occurred yesterday at 8:28 p.m. Eastern Daylight Time. The difference tells the Moon's current age. Does it break your personal record?

-Starting soon after sunset on Friday the 10th, use binoculars to look for the hairline Moon low near Venus. The Moon is much easier by Saturday the 11th.

-The visibility of the fainter objects in bright twilight is exaggerated here. These scenes are drawn for the middle of North America. European observers: move each Moon symbol a quarter of the way toward the one for the previous date. For clarity, the Moon is shown three times actual size.

May 9, 2013

-The famous binary star Gamma Virginis (Porrima) has widened to a separation of 2 arcseconds this spring, after being too close for amateur telescopes to resolve for much of the previous decade. It's the 3rd-magnitude star 15° upper right of Spica these evenings.

-New Moon, exact at 8:28 p.m. Eastern Daylight Time.

May 8, 2013

-SIf you're up around midnight, go out and look southeast for a preview of summery Scorpius rearing up into good view, sporting fiery Antares as its heart.

-The annular eclipse Australia will get to experience occurs tomorrow, May 10 [due to timezone differences].

May 7, 2013

-Summer is more than six weeks away, but the Summer Triangle is making its appearance in the east one star after another. The first in view is Vega. It's already visible low in the northeast as twilight fades.

-Next up is Deneb, lower left of Vega by two or three fists at arm's length. Deneb takes about an hour to appear after Vega does, depending on your latitude.

-The third is Altair, which doesn't show up far to their lower right until around midnight.

-Australia will be treated to an annular eclipse later in the week on May 10, as well as parts of Papua New Guinea.

May 6, 2013

-The brightest star high in the southeast after nightfall is Arcturus. Far to its lower right are Spica and, lower, Saturn. To the right of these two, look for the quadrilateral of Corvus, the Crow.

-Jupiter (magnitude –2.0, in Taurus) is the first "star" to come out in the west after sunset, a little lower every day. It descends in the evening and sets around 10 or 11 p.m. Above Jupiter is El Nath (Beta Tauri). Much farther to Jupiter's upper right is bright Capella.

-In a telescope, Jupiter has shrunk to a disappointing 33 arcseconds wide, about as small as it ever gets.

May 5, 2013

-The western Arch of Spring is on fine display in late twilight. Its top consists of Pollux and Castor high in the west. They're lined up roughly horizontally and are about three finger-widths at arm's length apart. Look far to their lower left for Procyon, and farther to their lower right for brighter Capella.

-Far below the arch this spring, two more points make it a pentagon. These are bright Jupiter and, about two fists to Jupiter's left, Betelgeuse.

May 4, 2013

-The three brightest stars in the May dusk are all zero magnitude: Capella in the northwest, Vega lower in the northeast, and Arcturus high in the east. (Jupiter, far lower left of Capella, is brighter but doesn't count.)

-The Eta Aquariid meteor shower, usually the year's best for the Southern Hemisphere, should be strongest just before dawn. Fewer of its meteors can be seen from the latitudes of the southern U.S., and few or none from the northern U.S. and Europe.

May 3, 2013

-As soon as it's fully dark, look for the Big Dipper very high in the north-northeast. It's upside down, with its handle to the right and its bowl to the left. It's "dumping water" onto the much dimmer Little Dipper down below.

May 2, 2013

-Last-quarter Moon. The Moon, between dim Capricornus and Aquarius, rises around the middle of the night (far below Altair). By daybreak Friday morning it's high in the south.

May 1, 2013

-Jupiter (magnitude –2.0, in Taurus) is the first "star" to come out in the west after sunset, a little lower every day. It descends in the evening and sets around 10 or 11 p.m. Below Jupiter twinkles orange Aldebaran, and a similar distance above Jupiter is El Nath (Beta Tauri). Bright Capella shines to the upper right from there. In a telescope, Jupiter has shrunk to a disappointing 34 arcseconds wide.

April 30, 2013

-The small but distinctive constellation Corvus, the Crow, is an icon of spring evenings (in the Northern Hemisphere). Look for its four-star quadrilateral in the south-southeast after dark, to the right of Saturn and Spica.

-Mars remains hidden in the glare of the Sun. Not until summer will it emerge in the dawn.

April 29, 2013

-It's almost May, yet the winter star Sirius still twinkles low above the west-southwest horizon in late twilight. How much later into the spring can you keep it in view?

-With your telescope, do you ever observe the lunar landscape when the Moon is waning before dawn and the terminator is lunar sunset rather than sunrise? Get up early this week and have a look at familiar features in this new light.

April 28, 2013

-The classic small-scope binary star Gamma Virginis, or Porrima, shines upper right of Spica, 14° from it (about a fist and a half at arm's length) these evenings. Porrima's two equal components were almost unresolvably close together for much of the last decade, but this spring they've widened to 2 arcseconds apart. Use high power.

-Venus (magnitude –3.9) is just beginning an evening apparition that will continue for the rest of the year. How soon can you first pick it up? Use binoculars to look for Venus a mere 15 or 20 minutes after sunset, barely above the west-northwest horizon. It's far to the lower right of Jupiter for viewers at mid-northern latitudes.

April 27, 2013

-The waning gibbous Moon rises in the southeast very late this evening, with the red supergiant Antares sparkling to its right. By early dawn Sunday morning Antares is below the Moon in the southwest.

-Saturn (magnitude +0.1, in Libra) is at opposition Saturday night April 27th. All week it glows low in the east-southeast as twilight fades (to the lower left of Spica and farther lower right of Arcturus). It rises it higher all evening and shines highest in the south in the middle of the night.

-Carefully note the brightness of the rings with respect to the globe. The rings always brighten for several days around opposition due to the Seeliger effect. The solid, very irregular particles of the rings preferentially reflect sunlight back in the direction it came from more than Saturn's cloudtops do. Watch as the rings dim back down later in the week, as Saturn moves away from the opposition point in Earth's sky.

-The Seeliger effect: Christopher Go took these images of Saturn on March 2nd (top) and April 24th. Notice how the rings brightened with respect to the globe. And on the 24th, Saturn was still three days from opposition.

April 26, 2013

-Around the end of twilight this evening, the Moon rises below Saturn. With binoculars, look closer below Saturn for the wide double star Alpha2 and Alpha1 Librae, magnitudes 2.8 and 5.2, respectively.

April 25, 2013

-Full Moon. A very slight partial lunar eclipse is visible from Europe, Africa, Australia, and most of Asia, centered on 20:07 April 25th Universal Time. Details are here: http://eclipse.gsfc.nasa.gov/OH/OH20...l#LE2013Apr25P

The "star" near the Moon all night is Saturn, just two days away from its own opposition.

April 24, 2013

-Look close to the nearly full Moon for Spica tonight. The Moon occults Spica for parts of Central America, South America, and southern Africa.

April 23, 2013

-There's a bright gibbous Moon tonight. If you're out with a telescope, you'll notice that the Moon is creeping toward a star: Chi Virginis, magnitude 4.7. The Moon's invisible dark limb, just beyond the terminator, will occult the star for most of North America except the Northeast and north of the Great Lakes. Some times of the star's disappearance: at Washington, DC, 12:20 a.m. EDT; Miami, 11:58 p.m. EDT; Chicago, 10:47 p.m. CDT; Austin, 10:17 p.m. CDT; Denver, 9:07 p.m. MDT; Los Angeles, 7:52 p.m. PDT.

April 22, 2013

-The two brightest points in the sky after dusk this week are Jupiter in the west and Sirius in the southwest. Midway between them is Orion. This lineup is lying down lower every week now. How late into the spring can you keep it in view?.

April 21, 2013

-The Lyrid meteor shower should peak before dawn Monday morning local time. Most years it's quite weak, but there have been surprises.

-This year the light of the nearly full Moon will interfere, but at least you can determine whether or not an outburst is in progress at the times you're looking. Watch late on the night of April 21st or before dawn's first light on April 22nd, when the shower's radiant (near Vega) is high in the sky.

April 20, 2013

-The Moon now shines under Regulus after dark.

-Be on the lookout for the Lyrid Meteor Shower, slated to peak tomorrow.

-Saturn (magnitude +0.1, in Libra) is nearing opposition. It glows low in the east-southeast as twilight fades, well to the lower left of Spica and farther lower right of brighter Arcturus. Saturn rises higher all evening and shines highest in the south around 1 a.m. daylight saving time. It's at opposition on the night of April 27th.

-Carefully note the brightness of Saturn's rings with respect to the globe. Keep watch. The rings brighten for a few days around opposition due to the Seeliger effect: the solid particles of the rings preferentially reflect sunlight back in the direction it came from, more than Saturn's cloudtops do.

-Below is Saturn on April 15th, imaged by Christopher Go in the Philippines using a Celestron 14 scope and a Point Grey Research monochrome Flea3 (ICX618) camera with Chroma Technology LRGB color filters. South is up. "The polar hexagon is prominent on this image," he writes. "Note the white spots on the North North Temperate Zone."

April 19, 2013

-Look for Regulus and the Sickle of Leo to the left of the Moon this evening, as shown here.

April 18, 2013

-The Moon is exactly first quarter at 8:31 a.m. EDT this morning, which means it looks equally "first quarter" on the evenings of the 17th and 18th from North America's eastern time zones. The Moon this evening is in dim Cancer, inside the big, long triangle of Procyon, Pollux, and Regulus.

April 17, 2013

-The Moon this evening is passing almost midway between Procyon to its lower left and Pollux to its upper right. Castor, slightly dimmer, shines to the right of Pollux.

April 16, 2013

-Look left of the Moon after dark for Procyon. High above the Moon is Pollux, with Castor at its right. Equally far below the Moon is Betelgeuse, the top corner of Orion.

-Saturn (magnitude +0.2, in Libra) glows low in the east-southeast by the end of twilight. Look for it well to the lower left of Spica, and farther lower right of brighter Arcturus. Saturn rises higher all evening. It shines highest in the south around 1 or 2 a.m. daylight saving time — more or less between Spica to its right, and Delta Scorpii (and then Antares) farther to its lower left. Saturn will reach opposition on the night of April 27th.

April 15, 2013

-The Moon right after dark is in the top of Orion's very dim Club. That's not far from the center of the huge Winter Hexagon: Sirius, Procyon, the Pollux-and-Castor pair, Capella, Aldebaran (under Jupiter), Rigel, and back to Sirius.

-Jupiter (magnitude –2.1, in Taurus) is the first "star" to come out in the west after sunset. It descends through the evening and sets around 11 or midnight. Below Jupiter is orange Aldebaran. Farther to Jupiter's lower right are the Pleiades. In a telescope, Jupiter has shrunk to just 35 arcseconds wide.

April 14, 2013

-The Moon and Jupiter shine side by side high in the west after dusk, 3° or 4° apart, with Aldebaran below them. Although they look close together, the Moon is 1.3 light-seconds from Earth, Jupiter is currently 47 light-minutes distant, and Aldebaran is 65 light-years in the background.

April 13, 2013

-The thin crescent Moon floats between Aldebaran and the Pleiades in the west as twilight fades, with Jupiter above it, as shown at right.

-Be on the look out for auroras based off the large CME the sun launched on April 11. The CME is expected to reach Earth at some point today. Pay attention to the aurora tracker as the day progresses.

April 12, 2013

-As twilight fades in the west this evening, look far to the lower left of Jupiter for the crescent Moon. Less far above the Moon, you can see the Pleiades emerging into view.

April 11, 2013

-Jupiter's moon Io reappears out of eclipse from Jupiter's shadow around 10:23 p.m. Eastern Daylight Time. Europa emerges from Jupiter's shadow around 10:11 p.m. Pacific Daylight Time. Both reappear just east of the planet.

April 10, 2013

-By 10 p.m. or later (depending on where you live), the bright "Summer Star" Vega is rising in the northeast, beginning a long evening apparition that will continue for the rest of the year.

-New Moon (exact at 5:35 a.m. EDT).

-Jupiter is on its way to passing directly above Aldebaran and the Hyades. (The blue 10° scale is about the width of your fist at arm's length.)

April 9, 2013

-The upright Sickle of Leo, with Regulus on the bottom of its handle, crosses the meridian high in the south these evenings. It's shaped like a backward question mark, and it stands about 1½ fist-widths tall.

-Jupiter is on its way to passing directly above Aldebaran and the Hyades. (The blue 10° scale is about the width of your fist at arm's length.)

April 8, 2013

-As spring advances, wintry Orion tilts farther over as it declines in the west-southwest after dark. Orion's Belt in its middle is now almost horizontal. Orion is brightly framed on its right by Jupiter and on its left by Sirius.

-Jupiter is on its way to passing directly above Aldebaran and the Hyades. (The blue 10° scale is about the width of your fist at arm's length.)

April 7, 2013

-From bright Arcturus in the east, look lower right by about three fists at arm's length for Spica and, lower down as evening grows late, Saturn. To the right of Spica by a little more than a fist is the four-star quadrilateral of Corvus, the Crow.

-Jupiter is on its way to passing directly above Aldebaran and the Hyades. (The blue 10° scale is about the width of your fist at arm's length.)

April 6, 2013

-Look for Arcturus, the "Spring Star," low in the east-northeast in twilight and higher in the east after dark. The constellation Bootes extends to its left. High to Arcturus's upper left is the Big Dipper.

-Just before dawn on April 4th, Sky&Telescope's Sean Walker took this image of Comet PanSTARRS passing 2.4° from M31, the Andromeda Galaxy. The galaxy is 2.5 million light-years away; the comet was 11 light-minutes away. Shooting from latitude 43° north in New Hampshire, Walker stacked 12 minutes of exposures (11 x 70 seconds) taken with a 180-mm lens at f/4 on a Canon 1000D camera at ISO 800.

April 5, 2013

-The huge, bright Winter Hexagon is still in view after dark, filling the sky to the southwest and west. Start at bright Sirius in the southwest. It marks the Hexagon's lower left corner. High above Sirius is Procyon. From there, look upper right to Pollux and Castor, lower right from Castor to Menkalinen and Capella, lower left to Aldebaran (with brighter Jupiter hogging the limelight near it!), lower left to Rigel at the bottom of Orion, and back to Sirius.

April 4, 2013

-Venus and Mars remain hidden in the glare of the Sun

-Jupiter (magnitude –2.1, in Taurus) comes into view high in the west after sunset, then descends as night grows late. Lower left of Jupiter is fainter orange Aldebaran. Farther to Jupiter's lower right are the Pleiades. They all set in the west-northwest around the middle of the night. In a telescope, Jupiter has shrunk to 36 arcseconds wide.

April 3, 2013

-Jupiter's moon Io crosses Jupiter's face from 7:56 to 10:08 p.m. EDT, followed by its tiny black shadow (much more visible) from 9:03 to 11:15 p.m. EDT.

-This evening Comet PanSTARRS, fading every day, is passing 2° west (lower right) of the Andromeda Galaxy, M31. They may appear about equally dim low in the northwest just as twilight is ending, for observers at fairly high northern latitudes. Think photo opportunity.

April 2, 2013

-As spring advances, wintry Orion tilts farther over as it declines in the west-southwest after dark. Orion's Belt in its middle is almost horizontal. Orion is brightly framed between Jupiter on its right and Sirius on its left.

-Last-quarter Moon tonight (exact at 12:37 a.m. Wednesday morning EDT).

April 1, 2013

-Happy April Fools! The red carbon stars U and V Hydrae, and the Ghost of Jupiter planetary nebula (magnitude 7.7), all reside within a few degrees of each other in central Hydra.

March 31, 2013

-The red carbon stars U and V Hydrae, and the Ghost of Jupiter planetary nebula (magnitude 7.7), all reside within a few degrees of each other in central Hydra.If you have binoculars, this is a good time of year to view them.

March 30, 2013

-Early Sunday morning, telescope users south of a line from central Florida through Oregon can watch the double star Beta Scorpii, magnitudes 2.6 and 4.8, emerge from behind the dark limb of the waning gibbous Moon. Map and timetables are found at the end of this post (for the bright component; the faint one emerges up to a minute or two earlier. Times are in Universal Time. Be sure to scroll down there to find the Reappearance timetable.) http://lunar-occultations.com/iota/bstar/0331zc2302.htm

March 29, 2013

-The waning Moon rises in the east quite late this evening. Look above it for the planet Saturn.

-This is the time of year when the dim Little Dipper juts to the right from Polaris (the Little Dipper's handle-end) during evening hours. The much brighter Big Dipper curls over high above it, "dumping water" into it.

March 28, 2013

-Once the Moon rises this evening, look upper right of it for Spica and lower left of it for Saturn, as shown at right.

March 27, 2013

-With spring under way, Algol in Perseus is heading down in the northwest after dusk. Your last chance to catch Algol in one of its eclipses this season may be the one this evening or the one Saturday evening. Tonight Algol should be at minimum brightness, magnitude 3.4 instead of its usual 2.1, for a couple hours centered on 9:43 p.m. Pacific Daylight Time. Easterners will have a better shot on Saturday. Algol takes several additional hours to fade and to rebrighten.

March 26, 2013

-Full Moon tonight (exact at 5:27 a.m. Wednesday morning EDT). The Moon this evening is far below Leo and above Spica and Corvus.

-Mercury (brightening from magnitude +0.6 to +0.2 this week) is having a poor apparition very low in the dawn. Use binoculars to scan for it just above the east-southeast horizon about 30 minutes before sunrise.

March 25, 2013

-Look northwest right after dark for W-shaped Cassiopeia standing on end. The brightest part of the W is on the bottom.

-Jupiter (magnitude –2.1, in Taurus) comes into view high in the west after sunset, then descends as night grows late. Lower left of Jupiter is orange Aldebaran. Farther to Jupiter's lower right are the Pleiades. They all set in the west-northwest around the middle of the night.

-Jupiter is not as bright as it used to be, and in a telescope it has shrunk to 36 arcseconds wide – from 48" around its opposition last December.

March 24, 2013

-Look above the Moon this evening for Regulus. It's the bottom star of the Sickle of Leo.

-Saturn (magnitude +0.3, in Libra) rises in the east-southeast only about an hour after the end of twilight now. Watch for it to make its appearance well to the lower left of Spica, and farther to the lower right of brighter Arcturus. Saturn shines highest in the south around 3 a.m. daylight saving time — more or less between Spica to its right, and Delta Scorpii and than Antares farther to its lower left. Saturn will come to opposition on the night of April 27th.

March 23, 2013

-Mercury (brightening from magnitude +0.6 to +0.2 this week) is having a poor apparition very low in the dawn. Use binoculars to scan for it just above the east-southeast horizon about 30 minutes before sunrise.

-Left of the Moon this evening are Regulus and the Sickle of Leo, as shown here. Farther lower right of the Moon is Alphard, the heart of Hydra. To the right or upper right of the Moon, can you make out Hydra's dim head?

March 22, 2013

-Now that spring is here, Orion is in the southwest after dark and leaning over to slide soon down to the horizon. Orion's three-star belt is turning nearly horizontal. He is framed by the two brightest starlike points in the sky: Jupiter off to his right and Sirius to his left.

-As the Moon waxes toward full, it walks between Leo and mostly-dim Hydra.

March 21, 2013

-High in the south after dusk, the Moon forms part of a big arc with Pollux and Castor to its upper right and Procyon below it.

-Saturn (magnitude +0.3, in Libra) rises in the east-southeast around 11 p.m. daylight saving time. Watch for it rising well to the lower left of Spica and farther to the lower right of brighter Arcturus. Saturn shines highest in the south in the early morning hours — more or less between Spica to its right and Antares farther to its lower left.
Saturn will come to opposition on the night of April 27th. In a telescope, Saturn's rings are now tilted a wide 19° from our line of sight.

March 20, 2013

-Comet PanSTARRS, for all the attention it's receiving, has turned out to be barely visible to the unaided eye, and only if you know exactly where to look. That would be low in twilight, due west or just a little to the right of due west now, about 45 minutes after sunset. This week the comet starts fading even as it gains a bit more altitude as seen from the world's mid-northern latitudes. Bring binoculars or, better, a low-power, wide-field telescope.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.


Source:
Comet PanSTARRS on March 17th. Earth's changing viewpoint toward its flat, thin dust tail is making the tail appear wider. Note the hint of a thin, straight ion (gas) tail just to the right of the curving dust tail's edge. Enhanced images show that it's real.

-Face southwest after dark. Very high there shines the Moon. Even higher (depending on where you live) are Pollux and Castor. To the Moon's left or lower left is Procyon.

-Spring begins in the Northern Hemisphere at the equinox, 7:02 a.m. EDT, when the Sun crosses the equators of both Earth and sky heading north for the year. In the Southern Hemisphere, fall begins.

March 19, 2013

-Comet PanSTARRS, for all the attention it's receiving, has turned out to be barely visible to the unaided eye, and only if you know exactly where to look. That would be low in twilight, due west or just a little to the right of due west now, about 45 minutes after sunset. This week the comet starts fading even as it gains a bit more altitude as seen from the world's mid-northern latitudes. Bring binoculars or, better, a low-power, wide-field telescope.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.

-First-quarter Moon (exact at 1:27 p.m. EDT). This evening the Moon shines between the feet of Gemini and the top of Orion's Club.

March 18, 2013

-Comet PanSTARRS, for all the attention it's receiving, has turned out to be barely visible to the unaided eye, and only if you know exactly where to look. That would be low in twilight, due west or just a little to the right of due west now, about 45 minutes after sunset. This week the comet starts fading even as it gains a bit more altitude as seen from the world's mid-northern latitudes. Bring binoculars or, better, a low-power, wide-field telescope.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.

-Look lower right of the Moon this evening for Jupiter, and upper right of the Moon for Beta Tauri (El Nath).

March 17, 2013

-Comet PanSTARRS, for all the attention it's receiving, has turned out to be barely visible to the unaided eye, and only if you know exactly where to look. That would be low in twilight, due west or just a little to the right of due west now, about 45 minutes after sunset. This week the comet starts fading even as it gains a bit more altitude as seen from the world's mid-northern latitudes. Bring binoculars or, better, a low-power, wide-field telescope.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.

-The Moon this evening passes right between Jupiter and Aldebaran, depending on your location. Gathered around are the Hyades, and nearby are the Pleiades. Think photo opportunity.

-Watch the Moon wax to, and through, the evening Jupiter group. (Drawn for the middle of North America. European observers: move each Moon symbol a quarter of the way toward the one for the previous date. The Moon is shown three times its actual size.)

March 16, 2013

-Comet PANSTARRS now makes its way to the northern hemisphere - however depending on your location it will be difficult to spot today and tomorrow.

-Look west after sunset near the horizon. Binoculars may be needed to pick Comet PanSTARRS out of the bright sky. Look too early and the sky will be too bright; too late and the comet will be too low. On the altitude scale at left, 10° is about the width of your fist held at arm's length.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.

-After dusk, the waxing Moon shines in the west with the Pleiades to its upper right and Jupiter and Aldebaran farther to its upper left, as shown here.

-Watch the Moon wax to, and through, the evening Jupiter group. (Drawn for the middle of North America. European observers: move each Moon symbol a quarter of the way toward the one for the previous date. The Moon is shown three times its actual size.)

March 15, 2013

-Comet PANSTARRS now makes its way to the northern hemisphere - however depending on your location it will be difficult to spot today and tomorrow.

-Look west after sunset near the horizon. Binoculars may be needed to pick Comet PanSTARRS out of the bright sky. Look too early and the sky will be too bright; too late and the comet will be too low. On the altitude scale at left, 10° is about the width of your fist held at arm's length.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.



Yesterday night instead of playing my tournament song for hours and hours I ventured out into one of the larger parks the city has, Downsview Park for a couple hours to spot Comet PANSTARRS. Two of the resulting images are shown here - one with a distant plane crossing in the distance, the other with an actual size view of PANSTARRS in the distance with a hydro pole as perspective.

-Look high above the Moon after dark for the Pleiades. Upper left of the Pleiades shines bright Jupiter with Aldebaran to its left, as shown here.

-As soon as it gets dark now, the Big Dipper has climbed as high in the northeast as Cassiopeia has sunk in the northwest.

-Watch the Moon wax to, and through, the evening Jupiter group. (Drawn for the middle of North America. European observers: move each Moon symbol a quarter of the way toward the one for the previous date. The Moon is shown three times its actual size.)

March 14, 2013

-Comet PANSTARRS now makes its way to the northern hemisphere - however depending on your location it will be difficult to spot today and tomorrow.

-Look west after sunset near the horizon. Binoculars may be needed to pick Comet PanSTARRS out of the bright sky. Look too early and the sky will be too bright; too late and the comet will be too low. On the altitude scale at left, 10° is about the width of your fist held at arm's length.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.


Source:*
Piotr Potepa in Torun, Poland, caught this image March 13th in bright twilight using a Nikon D700 for a 3-second exposure. The thin crescent moon owns the night, and the photographer nicely reaches out to the comet.

-The place to look for PanSTARRS now is two fists below the crescent Moon in twilight and perhaps a bit to the right.

March 13, 2013

-Comet PANSTARRS now makes its way to the northern hemisphere - however depending on your location it will be difficult to spot today and tomorrow.

-Look west after sunset near the horizon. Binoculars may be needed to pick Comet PanSTARRS out of the bright sky. Look too early and the sky will be too bright; too late and the comet will be too low. On the altitude scale at left, 10° is about the width of your fist held at arm's length.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.


Jose Galvez in Washington DC, USA, caught this image March 12th in bright twilight using a SONY DSC-HX200V for a 7-second exposure. The thin crescent moon and comet are clearly visible side by side.

-Comet PanSTARRS is now below the thickening crescent Moon 30 to 45 minutes after sunset, by about a fist-width at arm's length.

March 12, 2013

-Comet PANSTARRS now makes its way to the northern hemisphere - however depending on your location it will be difficult to spot today and tomorrow.

-Look west after sunset near the horizon. Binoculars may be needed to pick Comet PanSTARRS out of the bright sky. Look too early and the sky will be too bright; too late and the comet will be too low. On the altitude scale at left, 10° is about the width of your fist held at arm's length.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.

An accurate visual representation of what you can expect Comet PANSTARRS to look like in the bright twilight:

Toni Scarmato in Calabria, Italy, latitude 38°, caught this image March 10th in bright twilight using a 300-mm telephoto lens for a 1-second exposure. The frame is just 2.8° tall.

-Look very low in the west about 30 minutes after sunset for the thin waxing crescent Moon, not much more than 24 hours old, as shown at right. As seen from North America, Comet PanSTARRS is now left of the Moon by two or three finger-widths at arm's length. It's a hazy "star" with a thin, upward pointing tail only about 1° long. Bring binoculars for a better view.

-And think photo opportunity! Use a long or zoomed-out lens, and put your camera on a tripod because with a long lens in twilight, exposures won't be short. Experiment with a variety of exposures.

March 11, 2013

-Comet PANSTARRS now makes its way to the northern hemisphere - however depending on your location it will be difficult to spot today and tomorrow.

-Look west after sunset near the horizon. Binoculars may be needed to pick Comet PanSTARRS out of the bright sky. Look too early and the sky will be too bright; too late and the comet will be too low. On the altitude scale at left, 10° is about the width of your fist held at arm's length.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.

An accurate visual representation of what you can expect Comet PANSTARRS to look like in the bright twilight:

Toni Scarmato in Calabria, Italy, latitude 38°, caught this image March 10th in bright twilight using a 300-mm telephoto lens for a 1-second exposure. The frame is just 2.8° tall.

-It being March, bright Sirius is highest in the south on the meridian after dark. Sirius is the closest naked-eye star that's ever visible from mid-northern latitudes (aside from the Sun). It's only 8.6 light-years away.

-Using binoculars, look below Sirius by almost a binocular field-of-view for a dimly glowing patch among the stars. This is the open star cluster M41, 2,200 light-years away.

New Moon (exact at 3:51 p.m. Eastern Daylight Time).

March 10, 2013

-Comet PANSTARRS now makes its way to the northern hemisphere - however depending on your location it will be difficult to spot today and tomorrow.

-Look west after sunset near the horizon. Binoculars may be needed to pick Comet PanSTARRS out of the bright sky. Look too early and the sky will be too bright; too late and the comet will be too low. On the altitude scale at left, 10° is about the width of your fist held at arm's length.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.

-It's still winter, and in early evening Vega, the "Summer Star," is nowhere to be seen. But you can always tell where it is. Once again, find the Big Dipper standing in the northeast. The middle star of the Dipper's bent handle is Mizar, with faint little Alcor barely to its lower left. A line from Mizar through Alcor always points to Vega — currently well below the north horizon.

-Daylight-saving time begins at 2 a.m. Sunday morning in most of North America. Clocks spring ahead an hour.

March 9, 2013

-Comet PANSTARRS now makes its way to the northern hemisphere - however depending on your location it will be difficult to spot today and tomorrow.

-Look west after sunset near the horizon. Binoculars may be needed to pick Comet PanSTARRS out of the bright sky. Look too early and the sky will be too bright; too late and the comet will be too low. On the altitude scale at left, 10° is about the width of your fist held at arm's length.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.

-The Big Dipper glitters high in the northeast these evenings, standing on its handle. You probably know that the two stars forming the front of the Dipper's bowl (currently on top) are the Pointers; they point to Polaris, currently to their left.

And, you may know that if you follow the curve of the Dipper's handle out and around by a little more than a Dipper length, you'll arc to Arcturus, now rising in the east.

But did you know that if you follow the Pointers backward the opposite way, you'll land in Leo?

Draw a line diagonally across the Dipper's bowl from where the handle is attached, continue far on, and you'll go to Gemini.

And look at the two stars forming the open top of the Dipper's bowl. Follow this line past the bowl's lip far across the sky, and you crash into Capella.

March 8, 2013

-Comet PANSTARRS now makes its way to the northern hemisphere - however depending on your location it will be difficult to spot today and tomorrow.

-Look west after sunset near the horizon. Binoculars may be needed to pick Comet PanSTARRS out of the bright sky. Look too early and the sky will be too bright; too late and the comet will be too low. On the altitude scale at left, 10° is about the width of your fist held at arm's length.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.

-Jupiter is 5° from Aldebaran high in the west after dark. But it's now passing only 2° from fainter (3.5-magnitude) Epsilon Tauri, the other tip of the Hyades V pattern, located almost between them.

March 7, 2013

-Comet PANSTARRS now makes its way to the northern hemisphere - however depending on your location it will be difficult to spot today and tomorrow.

-Look west after sunset near the horizon. Binoculars may be needed to pick Comet PanSTARRS out of the bright sky. Look too early and the sky will be too bright; too late and the comet will be too low. On the altitude scale at left, 10° is about the width of your fist held at arm's length.

-This diagram is drawn for a viewer near 40° north latitude (Denver, New York, Madrid) 30 minutes after sunset. If you're south of there, the comet will be a little higher above your horizon early in the month than shown here. North of 40°, it will be a little lower early in March than shown here.

-Algol in Perseus should be at minimum light, magnitude 3.4 instead of its usual 2.1, for a couple hours centered on 9:58 p.m. Eastern Standard Time. Algol takes several additional hours to fade and to rebrighten.

March 6, 2013

-Mercury, Venus, and Mars are hidden in the glare of the Sun.

-Jupiter (bright at magnitude –2.3, in Taurus) comes into view high in the south-southwest after sunset and dominates the southwest to west later in the evening. Left of Jupiter is orange Aldebaran; farther to its lower right are the Pleiades. They all set in the west-northwest around midnight or 1 a.m.

In a telescope, Jupiter is shrinking as Earth pulls farther ahead of it in our faster orbit around the Sun. This week it shrinks from 39 to 38 arcseconds wide.

March 5, 2013

-On the traditional divide between the winter and spring sky is the dim constellation Cancer. It's between Gemini to its west and Leo to its east. Cancer has a unique feature: the Beehive Star Cluster, M44, in its middle. The Beehive shows to the naked eye only if your light pollution is slight. Look for it a little less than halfway from Pollux to Regulus. With binoculars it's a snap.

March 4, 2013
[left]-With Sirius on the meridian after dinnertime, so is the Winter Triangle — since Sirius is its bottom corner. The other two are Procyon to its upper left and Betelgeuse to its upper right. The Winter Triangle is almost perfectly equilateral: all three stars are 26° from each other within about 1° accuracy.

-Last-quarter Moon (exact at 4:53 p.m. EST).
March 3, 2013

-Jupiter's moon Europa disappears into eclipse by Jupiter's shadow around 7:10 p.m. EST, after reappearing from behind Jupiter's eastern limb just 14 minutes earlier. Io disappears behind Jupiter's other side 10 minutes later. Europa then reappears out of eclipse at 9:38 p.m. EST, followed by Io at 10:50 p.m. EST.

March 2, 2013

-Now that March has begun, Sirius takes over from Orion to stand at its highest in the south soon after dark

March 1, 2013

-Around 11 p.m. this evening (depending on where you live), the waning Moon rises with Saturn glowing a few degrees to its left, as shown above. The pair remain close for the rest of the night.

-Long awaited, Comet PanSTARRS now looks likely to reach about 2nd magnitude at its best in mid-March, when it will be low in the western evening twilight for Northern Hemisphere observers.

Astro Pic of the Day Archive March 1, 2013 - July 31, 2013

July 31, 2013

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How has the surface temperature of Earth been changing? To help find out, Earth scientists collected temperature records from over 1000 weather stations around the globe since 1880, and combined them with modern satellite data. The above movie dramatizes the result showing 130 years of planet-wide temperature changes relative to the local average temperatures in the mid-1900s. In the above global maps, red means warmer and blue means colder. On average, the display demonstrates that the temperature on Earth has increased by nearly one degree Celsius over the past 130 years, and many of the warmest years on record have occurred only recently. Global climate change is of more than passing interest - it is linked to global weather severity and coastal sea water levels.

July 30, 2013

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In 1787, astronomer William Herschel discovered the Eskimo Nebula. From the ground, NGC 2392 resembles a person's head surrounded by a parka hood. In 2000, the Hubble Space Telescope imaged the Eskimo Nebula in visible light, while the nebula was imaged in X-rays by the Chandra X-ray Observatory in 2007. The above combined visible-X ray image, with X-rays emitted by central hot gas and shown in pink, was released last week. From space, the nebula displays gas clouds so complex they are not fully understood. The Eskimo Nebula is clearly a planetary nebula, and the gas seen above composed the outer layers of a Sun-like star only 10,000 years ago. The inner filaments visible above are being ejected by strong wind of particles from the central star. The outer disk contains unusual light-year long orange filaments. The Eskimo Nebula spans about 1/3 of a light year and lies in our Milky Way Galaxy, about 3,000 light years distant, toward the constellation of the Twins (Gemini).

July 29, 2013

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This is not a solar eclipse. Pictured above is a busy vista of moons and rings taken at Saturn. The large circular object in the center of the image is Titan, the largest moon of Saturn and one of the most intriguing objects in the entire Solar System. The dark spot in the center is the main solid part of the moon. The bright surrounding ring is atmospheric haze above Titan, gas that is scattering sunlight to a camera operating onboard the robotic Cassini spacecraft. Cutting horizontally across the image are the rings of Saturn, seen nearly edge on. At the lower right of Titan is Enceladus, a small moon of Saturn. Since the image was taken pointing nearly at the Sun, the surfaces of Titan and Enceladus appear in silhouette, and the rings of Saturn appear similar to a photographic negative. Now if you look really really closely at Enceladus, you can see a hint of icy jets shooting out toward the bottom of the image. It is these jets that inspired future proposals to land on Enceladus, burrow into the ice, and search for signs of extraterrestrial life.

July 28, 2013

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Is this one galaxy or two? This question came to light in 1950 when astronomer Art Hoag chanced upon this unusual extragalactic object. On the outside is a ring dominated by bright blue stars, while near the center lies a ball of much redder stars that are likely much older. Between the two is a gap that appears almost completely dark. How Hoag's Object formed remains unknown, although similar objects have now been identified and collectively labeled as a form of ring galaxy. Genesis hypotheses include a galaxy collision billions of years ago and the gravitational effect of a central bar that has since vanished. The above photo taken by the Hubble Space Telescope in July 2001 revealed unprecedented details of Hoag's Object. More recent observations in radio waves indicate that Hoag's Object has not accreted a smaller galaxy in the past billion years. Hoag's Object spans about 100,000 light years and lies about 600 million light years away toward the constellation of the Snake (Serpens). Coincidentally, visible in the gap (at about one o'clock) is yet another ring galaxy that likely lies far in the distance.

July 27, 2013

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Storm clouds do sometimes come to Chile's Atacama desert, known as the driest place on Earth. These washed through the night sky just last month during the winter season, captured in this panoramic view. Drifting between are cosmic clouds more welcome by the region's astronomical residents though, including dark dust clouds in silhouette against the crowded starfields and nebulae of the central Milky Way. Below and right of center lies the Large Magellanic Cloud, appropriately named for its appearance in starry southern skies. City lights about 200 kilometers distant still glow along the horizon at the right, while bright star Canopus shines above them in the cloudy sky.

July 26, 2013

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The Elephant's Trunk Nebula winds through the emission nebula and young star cluster complex IC 1396, in the high and far off constellation of Cepheus. The cosmic elephant's trunk is over 20 light-years long. This composite was recorded through narrow band filters that transmit the light from ionized hydrogen, sulfur, and oxygen atoms in the region. The resulting image highlights the bright swept-back ridges that outline pockets of cool interstellar dust and gas. Such embedded, dark, tendril-shaped clouds contain the raw material for star formation and hide protostars within the obscuring cosmic dust. Nearly 3,000 light-years distant, the relatively faint IC 1396 complex covers a large region on the sky, spanning over 5 degrees. This close-up mosaic covers a 2 degree wide field, about the size of 4 Full Moons.

July 25, 2013

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The beautiful Trifid Nebula is a cosmic study in contrasts. Also known as M20, it lies about 5,000 light-years away toward the nebula rich constellation Sagittarius. A star forming region in the plane of our galaxy, the Trifid illustrates three different types of astronomical nebulae; red emission nebulae dominated by light emitted by hydrogen atoms, blue reflection nebulae produced by dust reflecting starlight, and dark nebulae where dense dust clouds appear in silhouette. The bright red emission region, roughly separated into three parts by obscuring dust lanes, lends the Trifid its popular name. But in this sharp, colorful scene, the red emission is also surrounded by the the telltale blue haze of reflection nebulae. Pillars and jets sculpted by newborn stars, below and left of the emission nebula's center, appear in Hubble Space Telescope close-up images of the region. The Trifid Nebula is about 40 light-years across.

July 24, 2013

http://vimeo.com/32095756

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Each panel shows one day. With 360 movie panels, the sky over (almost) an entire year is shown in time lapse format as recorded by a video camera on the roof of the Exploratorium museum in San Francisco, California. The camera recorded an image every 10 seconds from before sunrise to after sunset and from mid-2009 to mid-2010. A time stamp showing the local time of day is provided on the lower right. The videos are arranged chronologically, with July 28 shown on the upper left, and January 1 located about about half way down. Although every day lasts 24 hours, daylight lasts longest in the northern hemisphere in June and the surrounding summer months, a fact which can be seen here as the bottom (and soon top) videos are the first to light up with dawn. The initial darkness in the middle depicts the delayed dawn and fewer daylight hours of winter. In the videos, darkness indicates night, blue depicts clear day, while gray portrays pervasive daytime cloud cover. Many videos show complex patterns of clouds moving across the camera's wide field as that day progresses. As the videos collectively end, sunset and then darkness descend first on the winter days just above the middle, and last on the mid-summer near the bottom.

July 23, 2013

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In a cross-Solar System interplanetary first, our Earth was photographed during the same day from both Mercury and Saturn. Pictured on the left, Earth is the pale blue dot just below the rings of Saturn, as captured by the robotic Cassini spacecraft now the gas giant. Pictured on the right, the Earth-Moon system is seen against a dark background, as captured by the robotic MESSENGER spacecraft now orbiting Mercury. In the MESSENGER image, the Earth (left) and Moon (right) shine brightly with reflected sunlight. MESSENGER took the overexposed image last Friday as part of a search for small natural satellites of the innermost planet, moons that would be expected to be quite dim. The picture of Earth is only one footprint in a mosaic of 33 footprints covering the entire Saturn ring system. Researchers are working on the ensemble now, and they expect it to be ready in a few weeks.

July 22, 2013

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You are here. Everyone you've ever known is here. Every human who has ever lived - is here. Pictured above is the Earth-Moon system as captured by the Cassini mission orbiting Saturn in the outer Solar System. Earth is the brighter of the two spots near the center, while the Moon is visible to its lower left. The unprocessed image shows several streaks that are not stars but rather cosmic rays that struck the digital camera while it was taking the image. The image was snapped by Cassini on Friday and released on Saturday. At nearly the same time, many humans on Earth were snapping their own pictures of Saturn.

July 21, 2013

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Since Saturn's axis is tilted as it orbits the Sun, Saturn has seasons, like those of planet Earth ... but Saturn's seasons last for over seven years. So what season is it on Saturn now? Orbiting the equator, the tilt of the rings of Saturn provides quite a graphic seasonal display. Each year until 2016, Saturn's rings will be increasingly apparent after appearing nearly edge-on in 2009. The ringed planet is also well placed in evening skies providing a grand view as summer comes to Saturn's northern hemisphere and winter to the south. The Hubble Space Telescope took the above sequence of images about a year apart, starting on the left in 1996 and ending on the right in 2000. Although they look solid, Saturn's Rings are likely less than 50 meters thick and consist of individually orbiting bits of ice and rock ranging in size from grains of sand to barn-sized boulders.

July 20, 2013

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Now sweeping high above the ecliptic plane, Comet Lemmon has faded dramatically in planet Earth's night sky as it heads for the outer solar system. Some 16 light-minutes (2 AU) from the Sun, it still sports a greenish coma though, posing on the right in this 4 degree wide telescopic view from last Saturday with deep sky star clusters and nebulae in Cassiopeia. In fact, the rich background skyscape is typical within the boundaries of the boastful northern constellation that lie along the crowded starfields of the Milky Way. Included near center is open star cluster M52 about 5,000 light-years away. Around 11,000 light-years distant, the red glowing nebula NGC 7635 below and left of M52 is well-known for its appearance in close-up images as the Bubble Nebula. But the fading Comet Lemmon is not the only foreground object on the scene. A faint streak on the right is an orbiting satellite caught crossing through the field during the long exposure, glinting in the sunlight and winking out as it passes into Earth's shadow.

July 19, 2013

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Take a picture of Saturn in the sky tonight. You could capture a view like this one. Recorded just last month looking toward the south, planet Earth and ruins of the ancient temple of Athena at Assos, Turkey are in the foreground. The Moon rises at the far left of the frame and Saturn is the bright "star" at the upper right, near Virgo's alpha star Spica (picture with labels). If you do take a picture of Saturn or wave at Saturn and take a picture, you can share it online and submit it to the Saturn Mosaic Project. Why take a picture tonight? Because the Cassini spacecraft will be orbiting Saturn and taking a picture of you.

http://saturn.jpl.nasa.gov/news/waveatsaturn/

July 18, 2013

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Similar in size to large, bright spiral galaxies in our neighborhood, IC 342 is a mere 10 million light-years distant in the long-necked, northern constellation Camelopardalis. A sprawling island universe, IC 342 would otherwise be a prominent galaxy in our night sky, but it is hidden from clear view and only glimpsed through the veil of stars, gas and dust clouds along the plane of our own Milky Way galaxy. Even though IC 342's light is dimmed by intervening cosmic clouds, this deep telescopic image traces the galaxy's obscuring dust, blue star clusters, and glowing pink star forming regions along spiral arms that wind far from the galaxy's core. IC 342 may have undergone a recent burst of star formation activity and is close enough to have gravitationally influenced the evolution of the local group of galaxies and the Milky Way.

July 17, 2013

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Since 2011, the Earth to Sky students have flown 30 balloons and measured the temperature of the tropopause 19 times.The temperature of the tropopause on June 30, 2013 during a huge heat wave, fell right in the middle of their overall distribution - nothing unusual. These results show that hot air on the ground does not necessarily translate into a hot upper atmosphere. There was, however, something unusual about the flight. Normally, air above the Sierra launch site is crystal clear, but not this time. En route to the stratosphere, the balloon encountered many thin layers of smoke and ash blown into the area from distant wildfires. Each fire, apparently, lofted its aerosols to a different altitude where winds stretched the smoky debris into a thin layer. This picture was captured while the balloon was in transit between two layers. Note the curved blue line. That's the narrow gap between the two aerosol layers, allowing a glimpse of blue sky in the distance. (To residents of the eastern Sierra: That's Crowley Lake in the foreground.)

July 16, 2013

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Which moon is this? Earth's. Our Moon's unfamiliar appearance is due partly to an unfamiliar viewing angle as captured by a little-known spacecraft - the Soviet Union's Zond 8 that circled the Moon in October of 1970. Pictured above, the dark-centered circular feature that stands out near the top of the image is Mare Orientale, a massive impact basin formed by an ancient collision with an asteroid. Mare Orientale is surrounded by light colored and highly textured highlands. Across the image bottom lies the dark and expansive Oceanus Procellarum, the largest of the dark (but dry) maria that dominate the side of the Moon that always faces toward the Earth. Originally designed to carry humans, robotic Zond 8 came within 1000 km of the lunar surface, took about 100 detailed photographs on film, and returned them safely to Earth within a week.

July 15, 2013

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What's going on in the center of this spiral galaxy? Named the Sombrero Galaxy for its hat-like resemblance, M104 features a prominent dust lane and a bright halo of stars and globular clusters. Reasons for the Sombrero's hat-like appearance include an unusually large and extended central bulge of stars, and dark prominent dust lanes that appear in a disk that we see nearly edge-on. Billions of old stars cause the diffuse glow of the extended central bulge visible in the above image from the 200-inch Hale Telescope. Close inspection of the central bulge shows many points of light that are actually globular clusters. M104's spectacular dust rings harbor many younger and brighter stars, and show intricate details astronomers don't yet fully understand. The very center of the Sombrero glows across the electromagnetic spectrum, and is thought to house a large black hole. Fifty million-year-old light from the Sombrero Galaxy can be seen with a small telescope towards the constellation of Virgo.

July 14, 2013

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What lights up this castle of star formation? The familiar Eagle Nebula glows bright in many colors at once. The above image is a composite of three of these glowing gas colors. Pillars of dark dust nicely outline some of the denser towers of star formation. Energetic light from young massive stars causes the gas to glow and effectively boils away part of the dust and gas from its birth pillar. Many of these stars will explode after several million years, returning most of their elements back to the nebula which formed them. This process is forming an open cluster of stars known as M16.

July 13, 2013

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Reddened rays of the setting Sun flooded the skies over Cedar Creek Lake, southeast of Dallas, Texas, planet Earth on July 6th. And while sunsets may be the most watched celestial event, this one even offered something extra. A sunspot so large it was visible to the naked eye is captured in the serene sunset view, near the center of a solar disk dimmed and distorted by Earth's dense atomosphere. Telescopic views revealed the spot to be a complex of large solar active regions composed of sunspots, some larger than planet Earth itself.

July 12, 2013

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This fifteen degree wide field of view stretches across the crowded starfields of Sagittarius toward the center of our Milky Way galaxy. In fact, the center of the galaxy lies near the right edge of the rich starscape and eleven bright star clusters and nebulae fall near the center of the frame. All eleven are numbered entries in the catalog compiled by 18th century cosmic tourist Charles Messier. Achieving celebrity status for skygazers, M8 (Lagoon), M16 (Eagle), M17 (Omega), and M20 (Trifid) show off the telltale reddish hues of emission nebulae associated with star forming regions. But also eye-catching in small telescopes are star clusters in the crowded region; M18, M21, M22, M23, M25, and M28. Broader in extent than the star clusters themselves, M24 is actually a cloud of the Milky Way's stars thousands of light-years long, seen through a break in the galaxy's veil of obscuring dust. You can put your cursor over the image (or click here) for help identifying Messier's eleven.

July 11, 2013

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This complex of dusty nebulae linger along the edge of the Taurus molecular cloud, a mere 450 light-years distant. Stars are forming on the cosmic scene, including extremely youthful star RY Tauri prominent toward the upper left of the 1.5 degree wide telescopic field. In fact RY Tauri is a pre-main sequence star, embedded in its natal cloud of gas and dust, also cataloged as reflection nebula vdB 27. Highly variable, the star is still relatively cool and in the late phases of gravitational collapse. It will soon become a stable, low mass, main sequence star, a stage of stellar evolution achieved by our Sun some 4.5 billion years ago. Another pre-main sequence star, V1023 Tauri, can be spotted below and right, embedded in its yellowish dust cloud adjacent to the striking blue reflection nebula Ced 30.

July 10, 2013

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One of the largest sunspot regions in recent years is now crossing the Sun. This region of convoluted magnetic fields may well produce a solar flare that releases a cloud of energetic particles into the Solar System. Were a very powerful cloud to impact the Earth's magnetosphere, it could be dangerous to Earth-orbiting astronauts and satellites. Conversely, the impact of even a less energetic cloud might create picturesque aurora. Pictured above is the sunspot region as it appeared two days ago. The rightmost part of this region has been cataloged as AR 11785, while the left part as AR 11787. The darkest sunspot regions contain nearly vertical magnetic fields and are called umbras, while the surrounding bronze regions - more clearly showing stringy magnetic flux tubes - are called penumbras. Churning solar granules, many about 1000 km across, compose the yellow background region. No one knows what this sunspot region will do, but space weather researchers are monitoring it closely.

July 9, 2013

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Supergiant star Gamma Cygni lies at the center of the Northern Cross, a famous asterism in the constellation of the Swan (Cygnus). Known by the proper name Sadr, the bright star also lies at the center of this gorgeous skyscape, featuring a complex of stars, dust clouds, and glowing nebulae along the plane of our Milky Way galaxy. The field of view spans over 3 degrees (six Full Moons) on the sky and includes emission nebula IC 1318 and open star cluster NGC 6910. Left of Gamma Cygni and shaped like two glowing cosmic wings divided by a long dark dust lane, IC 1318's popular name is understandably the Butterfly Nebula. Above and slightly left of Gamma Cygni, are the young, still tightly grouped stars of NGC 6910. Some distance estimates for Gamma Cygni place it at around 750 light-years while estimates for IC 1318 and NGC 6910 range from 2,000 to 5,000 light-years.

July 8, 2013

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Pluto's newly discovered moons now have names. Known previously as P4 and P5, the International Astronomical Union has now given the fourth and fifth discovered moons of Pluto the names Kerberos and Styx. The small moons were discovered in 2011 and 2012 by the Hubble Space Telescope in preparation for the close passing of the New Horizons spacecraft by Pluto in 2015. Keberos is named for the many headed dog in Greek mythology that guards the entrance to the underworld, while Styx is named for the goddess who overlooks the mythological river that runs between the Earth and the underworld. Both monikers are related to the name of Pluto, who rules the mythical nether region. Because their reflectively is unknown, the size of each moon is quite uncertain - but each is crudely estimated to be about 20 kilometers in diameter. The robotic New Horizons spacecraft is on schedule to pass by Pluto in 2015 and provide the first clear images of the dwarf planet and its companions.

July 7, 2013

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In this beautiful celestial still life composed with a cosmic brush, dusty nebula NGC 2170 shines at the upper left. Reflecting the light of nearby hot stars, NGC 2170 is joined by other bluish reflection nebulae, a compact red emission region, and streamers of obscuring dust against a backdrop of stars. Like the common household items still life painters often choose for their subjects, the clouds of gas, dust, and hot stars pictured here are also commonly found in this setting - a massive, star-forming molecular cloud in the constellation of the Unicorn (Monoceros). The giant molecular cloud, Mon R2, is impressively close, estimated to be only 2,400 light-years or so away. At that distance, this canvas would be about 15 light-years across.

July 6, 2013

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The universe is filled with galaxies. But to see them astronomers must look out beyond the stars of our own galaxy, the Milky Way. This colorful Hubble Space Telescopic portrait features spiral galaxy NGC 6384, about 80 million light-years away in the direction of the constellation Ophiuchus. At that distance, NGC 6384 spans an estimated 150,000 light-years, while the Hubble close-up of the galaxy's central region is about 70,000 light-years wide. The sharp image shows details in the distant galaxy's blue star clusters and dust lanes along magnificent spiral arms, and a bright core dominated by yellowish starlight. Still, the individual stars seen in the picture are all in the relatively close foreground, well within our own galaxy. The brighter Milky Way stars show noticeable crosses, or diffraction spikes, caused by the telescope itself.

July 5, 2013

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Some 13,000 light-years away toward the southern constellation Pavo, the globular star cluster NGC 6752 roams the halo of our Milky Way galaxy. Over 10 billion years old, NGC 6752 follows clusters Omega Centauri and 47 Tucanae as the third brightest globular in planet Earth's night sky. It holds over 100 thousand stars in a sphere about 100 light-years in diameter. Telescopic explorations of the NGC 6752 have found that a remarkable fraction of the stars near the cluster's core, are multiple star systems. They also reveal the presence of blue straggle stars, stars which appear to be too young and massive to exist in a cluster whose stars are all expected to be at least twice as old as the Sun. The blue stragglers are thought to be formed by star mergers and collisions in the dense stellar environment at the cluster's core. This sharp color composite also features the cluster's ancient red giant stars in yellowish hues.

July 4, 2013

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Also known as the Cigar Galaxy for its elongated visual appearance, M82 is a starburst galaxy with a superwind. In fact, through ensuing supernova explosions and powerful winds from massive stars, the burst of star formation in M82 is driving a prodigious outflow of material. Evidence for the superwind from the galaxy's central regions is clear in this sharp telescopic snapshot. The composite image highlights emission from long outflow filaments of atomic hydrogen gas in reddish hues. Some of the gas in the superwind, enriched in heavy elements forged in the massive stars, will eventually escape into intergalactic space. Including narrow band image data in the deep exposure has revealed a faint feature dubbed the cap. Perched about 35,000 light-years above the galaxy at the upper left, the cap appears to be galactic halo material ionized by the superwind shock or intense ultraviolet radiation from the young, massive stars in the galaxy's core. Triggered by a close encounter with nearby large galaxy M81, the furious burst of star formation in M82 should last about 100 million years or so. M82 is 12 million light-years distant, near the northern boundary of Ursa Major.

July 3, 2013

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It may appear, at first, like the Galaxy is producing the lightning, but really it's the Earth. In the foreground of the above picturesque nighttime landscape is the Greek Island of Corfu, with town lights surrounding Lake Korrision. Visible farther in the distance are lights from the town of Preveza on the Greek mainland. In the more distant sky a thunderstorm is threatening, with two lightning strokes caught together during this 45 second wide-angle exposure taken in mid-May. The lightning branch on the left appears to be striking near Preveza, whereas the lightning strike on the right appears to be striking near Mount Ainos on the Greek Island of Cephalonia. Much farther in the distance, strewn about the sky, are hundreds of stars in the neighborhood of our Sun in the Milky Way Galaxy. Furthest away, arching over the entire panorama, are billions of stars that together compose the central band of our Milky Way.

July 2, 2013

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What would it look like to go right up to a black hole? One particularly interesting place near a black hole is its photon sphere, where photons can orbit in circles, a sphere 50 percent further out than the event horizon. Were you to look out from the photon sphere of a black hole, half of the sky would appear completely black, half of the sky would appear unusually bright, and the back of your head would appear across the middle. The above computer-animated video depicts this view from the photon sphere. The reason that the lower region, as shown, appears black is because all light paths from this dark region comes up from the black hole - which classically emits no light. The upper half of the sky now appears unusually bright, blueshifted, and shows increasingly many complete sky images increasingly close to the dark-light divide across the middle. That dark-light divide is the photon sphere - your location - and since photons can do circles there, light from the back of your head can circle the black hole and come to your eye. No place on the sky is hidden from you - stars that would normally pass behind the black hole now appear to zip quickly around an Einstein ring, a ring that appears above as a horizontal line about a quarter of the way down from the video top. (Disclosure: Video creator Robert Nemiroff is an editor for APOD.)

July 1, 2013

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On June 28, Earth passed through a region of south-pointing magnetism in the solar wind. The encounter set off one of the finest geomagnetic storms of the current solar cycle. At its peak on June 29th, the strong (Kp=7) storm filled the sky over Alberta Canasa with bright green auroras:

"With advance warning from Spaceweather.com, I headed out Friday night to a wind farm near my rural home, to take images of what I hoped would be an all-sky aurora. It did not disappoint!" says photographer Alan Dyer of Drumheller, Alberta. "These images are taken from the base of one of the massive wind machines, seemingly aimed into the aurora blown by the solar wind."

For a brief time, the auroras spilled across the Canadian border into the USA as south as Iowa, Oregon, Nebraska, and Kansas. In total, observers in more than a dozen US states reported visual or photographic sightings of auroras.

June 30, 2013

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What lies at the bottom of Hyperion's strange craters? Nobody's sure. To help find out, the robot Cassini spacecraft now orbiting Saturn swooped past the sponge-textured moon in 2005 and 2010 and took images of unprecedented detail. An image from the 2005 pass, shown above in false color, shows a remarkable world strewn with strange craters and a generally odd surface. The slight differences in color likely show differences in surface composition. At the bottom of most craters lies some type of unknown dark material. Inspection of the image shows bright features indicating that the dark material might be only tens of meters thick in some places. Hyperion is about 250 kilometers across, rotates chaotically, and has a density so low that it might house a vast system of caverns inside.

June 29, 2013

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Once known as Earth's sunset comet, PanSTARRS (C/2011 L4) is up all night now, but only for northern hemisphere skygazers. Telescopes are required to track its progress as it fades and heads for the outer solar system. But because planet Earth passed through the comet's orbital plane in late May, PanSTARRS will also be remembered for its remarkably long anti-tail. That edge-on perspective looking along the broad, fanned-out dust tail as it trailed behind the comet created the appearance of an anti-tail pointing in the sunward direction, back toward the inner solar system. Recorded on the night of May 27, this 13 pane mosaic (shown in positive and negative views) follows PanSTARRS' anti-tail as it stretches over 7 degrees from the comet's coma at the far right. The anti-tail was likely much longer, but gets lost in the evening's bright moonlight encroaching on the left edge of the scene. Background star cluster NGC 188 in Cepheus shows up along the way, near top left.

June 28, 2013

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A Full Perigee Moon rose as the Sun set last Sunday. At its closest to Earth it was, by just a bit, the year's brightest and largest Full Moon also known as a Super Moon. Seen from Punta Piedras, Argentina and the mouth of the Rio de La Plata, near Buenos Aires, the Super Moon's light created this magnificent circular lunar halo. Still, the size of a lunar halo is determined by the geometry of six sided water ice crystals in planet Earth's high, thin clouds. The crystals deflect the rays of moonlight more strongly through a minimum angle of 22 degrees. So this halo has an inner radius of 22 degrees, just like the halos of the less-than-super moons. Even more common than a Super Moon, beautiful 22 degree halos can be spotted at any time of year.

June 27, 2013

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This panoramic night scene from June 8 looks out across a Moscow skyline from atop the main building of Lomonosov Moscow State University. Shining in the darkened sky above are widespread noctilucent clouds. From the edge of space, about 80 kilometers above Earth's surface, the icy clouds can still reflect sunlight even though the Sun itself is below the horizon as seen from the ground. Usually spotted at high latitudes in summer months the diaphanous apparitions, also known as polar mesospheric clouds, have come early this season. The seasonal clouds are understood to form as water vapor driven into the cold upper atmosphere condenses on the fine dust particles supplied by meteor smoke (debris left by disintegrating meteors) or volcanic ash. Their early start this year may be connected to changing global circulation patterns in the lower atmosphere. During this northern summer, NASA's AIM mission provides daily projections of the noctilucent clouds as seen from space.

June 26, 2013

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Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it. The several distinct stars that surround Andromeda's image are actually stars in our Galaxy that are well in front of the background object. Andromeda is frequently referred to as M31 since it is the 31st object on Messier's list of diffuse sky objects. M31 is so distant it takes about two million years for light to reach us from there. Although visible without aid, the above image of M31 was taken with a small telescope. Much about M31 remains unknown, including how it acquired its unusual double-peaked center.

June 25, 2013

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This is Mars - have a look around. More specifically, this is one area picked for its promise of holding clues to the habitability of Mars to ancient life. To better search for telling leads, the robotic Curiosity rover took a series of detailed images from a location called Rock Nest. Over 900 of these images were then composed into one of the highest resolution images ever created of the red planet - a composite containing over one billion pixels. Shown above, toward the middle of this image mosaic, is Mt. Sharp, the central peak of the large crater where the Curiosity rover landed and is currently exploring. An interactive and zoomable version of this image is available here. Over the next few years, Curiosity is scheduled to roll toward the peak of ancient Mt. Sharp, all the while keeping a lookout for distinguishing geological and chemical markers.

June 24, 2013

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What's happening to this spiral galaxy? Just a few hundred million years ago, NGC 2936, the upper of the two large galaxies shown, was likely a normal spiral galaxy - spinning, creating stars - and minding its own business. But then it got too close to the massive elliptical galaxy NGC 2937 below and took a dive. Dubbed the Porpoise Galaxy for its iconic shape, NGC 2936 is not only being deflected but also being distorted by the close gravitational interaction. A burst of young blue stars forms the nose of the porpoise toward the left of the upper galaxy, while the center of the spiral appears as an eye. Alternatively, the galaxy pair, together known as Arp 142, look to some like a penguin protecting an egg. Either way, intricate dark dust lanes and bright blue star streams trail the troubled galaxy to the lower right. The above recently-released image showing Arp 142 in unprecedented detail was taken by the Hubble Space Telescope last year. Arp 142 lies about 300 million light years away toward the constellation, coincidently, of the Water Snake (Hydra). In a billion years or so the two galaxies will likely merge into one larger galaxy.

June 23, 2013

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If you could look across Venus with radar eyes, what might you see? This computer reconstruction of the surface of Venus was created from data from the Magellan spacecraft. Magellan orbited Venus and used radar to map our neighboring planet's surface between 1990 and 1994. Magellan found many interesting surface features, including the large circular domes, typically 25-kilometers across, that are depicted above. Volcanism is thought to have created the domes, although the precise mechanism remains unknown. Venus' surface is so hot and hostile that no surface probe has lasted more than a few minutes.

June 22, 2013

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As of today, our Sun begins its southern movement as a result we will experience shorter days. In the Netherlands, the duration of the day is now 16 hours and 45 minutes. With an empty beercan, many visitors of the Philippus Lansbergen Observatory in Middelburg, the Netherlands, captured the movement of the Sun with a single six month long exposure. The first solargraphs have been revealed, and this is the result of the sun's movement over the course of six months. This photo was taken by Jan Koeman. Missing sections represent cloudy ovvercast days. The general view that the Netherlands is often cloudy seems to be incorrect in the past six months as there is a large amount of sunlight present in the photo.

June 21, 2013

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Today, the solstice is at 05:04 Universal Time, the Sun reaching the northernmost declination in its yearly journey through planet Earth's sky. A June solstice marks the astronomical beginning of summer in the northern hemisphere and winter in the south. It also brings the north's longest day, the longest period between sunrise and sunset. This composite image follows the Sun's path toward the end of the June solstice day of 2012 as it approaches the western horizon in a colorful, clear sky. The scene looks north and west along the Tyrrhenian Sea coast from Santa Severa, Italy. Appearing in the well-timed sequence, the small figure of the photographer himself is illuminated against the wall of the town's medieval castle.

June 20, 2013

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Sharp telescopic views of magnificent edge-on spiral galaxy NGC 3628 show a puffy galactic disk divided by dark dust lanes. Of course, this deep galactic portrait puts some astronomers in mind of its popular moniker, The Hamburger Galaxy. The tantalizing island universe is about 100,000 light-years across and 35 million light-years away in the northern springtime constellation Leo. NGC 3628 shares its neighborhood in the local Universe with two other large spirals M65 and M66 in a grouping otherwise known as the Leo Triplet. Gravitational interactions with its cosmic neighbors are likely responsible for the extended flare and warp of this spiral's disk.

June 19, 2013

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How many different astronomical phenomena have come together to create the above vista? Several. First, in the foreground, is Crater Lake - a caldera created by volcanism on planet Earth about 7,700 years ago. Next, inside the lake, is water. Although the origin of the water in the crater is melted snowfall, the origin of water on Earth more generally is unclear, but possibly related to ancient Earthly-impacts of icy bodies. Next, the green glow in the sky is airglow, light emitted by atoms high in the Earth's atmosphere as they recombine at night after being separated during the day by energetic sunlight. The many points of light in the sky are stars, glowing by nuclear fusion. They are far above the atmosphere but nearby to our Sun in the Milky Way Galaxy. Finally, the bright arch across the image is the central band of the Milky Way, much further away, on the average, than the nearby stars, and shaped mostly by gravity. Contrary to appearances, the Milky Way band glows by itself and is not illuminated by the airglow. The above image is a six-frame panorama taken during about two weeks ago in Oregon, USA.

June 18, 2013

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Consider it a solar eclipse ... of Jupiter. On June 19th the sun will pass directly in front of Jupiter, completely eclipsing the giant planet. Coronagraphs onboard the Solar and Heliospheric Observatory are monitoring the convergence. The CME in the movie was blasted into space by a farside active region described in today's lead news item. Jupiter appears to be in the line of fire, but it is not. The cloud is merely passing in front of the planet; even the CMEs are eclipsing Jupiter today. Updated images of the "eclipse" may be found at the SOHO Realtime Images web page. http://sohowww.nascom.nasa.gov/data/...me-images.html

June 17, 2013

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What creates these long and nearly straight grooves on Mars? Dubbed linear gullies, they appear on the sides of some sandy slopes during Martian spring, have nearly constant width, extend for as long as two kilometers, and have raised banks along their sides. Unlike most water flows, they do not appear to have areas of dried debris at the downhill end. A leading hypothesis - actually being tested here on Earth - is that these linear gullies are caused by chunks of carbon dioxide ice (dry ice) breaking off and sliding down hills while sublimating into gas, eventually completely evaporating into thin air. The above recently-released image was taken in 2006 by the HiRISE camera on board the NASA's Mars Reconnaissance Orbiter currently orbiting Mars.

June 16, 2013

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Taken by Maximilian Teodorescu on June 15, 2013 @ Dumitrana (Ilfov), Romania, using a SW Mak 150mm (F/12), Canon 550D, ISO 800, 1/1250s. The Moon is waxing full this week, which means there's more bright territory for spaceships to cross. Yesterday, astrophotographer Maximilian Teodorescu of Dumitrana, Romania, caught the International Space Station passing in front of the Moon in broad daylight. "In the past I have captured the silhouette of the ISS in front of the Sun or Moon," says Teodorescu. But this time the ISS was not silhouetted. It was even more brightly lit than the Moon behind it. "I photographed them both in plain daylight, with the Sun still hanging at 26 degrees above the horizon."

Travelling at 17,000 mph, the ISS flits across the face of the Moon in only a fraction of a second. Teodorescu knew when to activate his Canon 550D digital camera using precise transit predictions from CalSky.

June 15, 2013

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Over a five hour period last Tuesday morning, exposures captured this tantalizing view of meteor streaks and the Milky Way in dark skies above Las Campanas Observatory in Chile. During that time, astronomers had hoped to see an outburst from the gamma Delphinid meteor shower as Earth swept through the dust trail left by an unknown comet. Named for the shower's radiant point in the constellation Delphinus, a brief but strong outburst was reported in bright, moonlit skies on June 10, 1930. While no strong Delphinid meteor activity was reported since, an outburst was tentatively predicted to occur again in 2013. But even though Tuesday's skies were dark, the overall rate of meteors in this field is low, and only the three lower meteor streaks seem to point back to the shower's estimated radiant.

June 14, 2013

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Sharpless 115 stands just north and west of Deneb, the alpha star of Cygnus the Swan in planet Earth's skies. Noted in the 1959 catalog by astronomer Stewart Sharpless (as Sh2-115) the faint but lovely emission nebula lies along the edge one of the outer Milky Way's giant molecular clouds, about 7,500 light-years away. Shining with the light of ionized atoms of hydrogen, sulfur, and oxygen in this Hubble palette color composite image, the nebular glow is powered by hot stars in star cluster Berkeley 90. The cluster stars are likely only 100 million years old or so and are still embedded in Sharpless 115. But the stars' strong winds and radiation have cleared away much of their dusty, natal cloud. At the emission nebula's estimated distance, this cosmic close-up spans just under 100 light-years.

June 13, 2013

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You can see four planets in this serene sunset image, created from a series of stacked digital exposures captured near dusk on May 25. The composite picture follows the trail of three of them, Jupiter, Venus, and Mercury (left to right) dropping toward the western horizon, gathered close in last month's remarkable triple planetary conjunction. Similar in brightness to planet Mercury, the star Elnath (Beta Tauri) is also tracked across the scene, leaving its dotted trail still farther to the right. Of course, in the foreground are the still, shallow waters of Alikes salt lake, reflecting the striking colors of sunset over Kos Island, Greece, planet Earth. For now, Jupiter has wandered into the glare of the setting Sun, but Mercury and Venus remain low in the west at twilight.

June 12, 2013

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For the first time, the entire surface of planet Mercury has been mapped. Detailed observations of the innermost planet's surprising crust have been ongoing since the robotic MESSENGER spacecraft first passed Mercury in 2008 and began orbiting in 2011. Previously, much of the Mercury's surface was unknown as it is too far for Earth-bound telescopes to see clearly, while the Mariner 10 flybys in the 1970s observed only about half. The above video is a compilation of thousands of images of Mercury rendered in exaggerated colors to better contrast different surface features. Visible on the rotating world are rays emanating from a northern impact that stretch across much of the planet, while about half-way through the video the light colored Caloris Basin rotates into view, a northern ancient impact feature that filled with lava. MESSENGER has now successfully completed its primary and first extended missions.

June 11, 2013

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What's happening in the NGC 3582 nebula? Bright stars and interesting molecules are forming. The complex nebula resides in the star forming region called RCW 57. Visible in this image are dense knots of dark interstellar dust, bright stars that have formed in the past few million years, fields of glowing hydrogen gas ionized by these stars, and great loops of gas expelled by dying stars. A detailed study of NGC 3582, also known as NGC 3584 and NGC 3576, uncovered at least 33 massive stars in the end stages of formation, and the clear presence of the complex carbon molecules known as polycyclic aromatic hydrocarbons (PAHs). PAHs are thought to be created in the cooling gas of star forming regions, and their development in the Sun's formation nebula five billion years ago may have been an important step in the development of life on Earth. The above image was taken at the Desert Hollow Observatory north of Phoenix, Arizona, USA.

June 10, 2013

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Where are the hottest stars in the nearest galaxies? To help find out, NASA commissioned its Earth-orbiting Swift satellite to compile a multi-image mosaic of the neighboring Large Magellanic Cloud (LMC) galaxy in ultraviolet light. The above image shows where recently formed stars occur in the LMC, as the most massive of these young stars shine brightly in blue and ultraviolet. In contrast, a more familiar view of the LMC in visible light better highlights older stars. On the upper left is one of the largest star forming regions known in the entire Local Group of galaxies: the Tarantula Nebula. The Large Magellanic Cloud and its smaller companion the Small Magellanic Cloud are easily visible with the unaided eye to sky enthusiasts with a view of the southern sky. Detailed inspection of the above image is allowing a better galaxy-comprehensive picture for how star formation occurs.

June 9, 2013

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On the afternoon of June 5th, the European Space Agency launched a robotic spaceship named "Albert Einstein" into Earth orbit. Also known as "ATV-4" (Automated Transfer Vehicle 4), the Albert Einstein is a cargo carrier laden with supplies for the International Space Station. Marco Langbroek saw it flying over Leiden, the Netherlands, just two hours after launch:

"The ATV-4 was very bright (mag +1 to +0.5) and easily visible to the naked eye, even from Leiden center," Langbroek. "Still in a low orbit, it was very fast."

To resupply the space station, the Albert Einstein is carrying the most dry cargo ever launched by a European spacecraft - 2,480 kilograms, and the most diverse cargo mix - 1400 different items. It will catch up to and dock with the ISS on June 15th. As that date approaches, the ATV-4 and the ISS will become visible in the night sky at the same time.

June 8, 2013

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Many bright nebulae and star clusters in planet Earth's sky are associated with the name of astronomer Charles Messier, from his famous 18th century catalog. His name is also given to these two large and remarkable craters on the Moon. Standouts in the dark, smooth lunar Sea of Fertility or Mare Fecunditatis, Messier (left) and Messier A have dimensions of 15 by 8 and 16 by 11 kilometers respectively. Their elongated shapes are explained by an extremely shallow-angle trajectory followed by the impactor, moving left to right, that gouged out the craters. The shallow impact also resulted in two bright rays of material extending along the surface to the right, beyond the picture. Intended to be viewed with red/blue glasses (red for the left eye), this striking stereo picture of the crater pair was recently created from high resolution scans of two images (AS11-42-6304, AS11-42-6305) taken during the Apollo 11 mission to the moon.

June 7, 2013

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The bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects. Though its wingspan covers over 3 light-years, NGC 6302 is no exception. With an estimated surface temperature of about 250,000 degrees C, the dying central star of this particular planetary nebula has become exceptionally hot, shining brightly in ultraviolet light but hidden from direct view by a dense torus of dust. This sharp and colorful close-up of the dying star's nebula was recorded in 2009 by the Hubble Space Telescope's Wide Field Camera 3, installed during the final shuttle servicing mission. Cutting across a bright cavity of ionized gas, the dust torus surrounding the central star is near the center of this view, almost edge-on to the line-of-sight. Molecular hydrogen has been detected in the hot star's dusty cosmic shroud. NGC 6302 lies about 4,000 light-years away in the arachnologically correct constellation of the Scorpion (Scorpius).

June 6, 2013

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Although you've surely seen it, you might not have noticed it. During a cloudless twilight, just before sunrise or after sunset, part of the atmosphere above the horizon appears slightly off-color, slightly pink. Called the Belt of Venus, this off-color band between the dark eclipsed sky and the blue sky can be seen in nearly every direction including that opposite the Sun. Straight above, blue sky is normal sunlight reflecting off the atmosphere. In the Belt of Venus, however, the atmosphere reflects light from the setting (or rising) Sun which appears more red. The Belt of Venus can be seen from any location with a clear horizon. Pictured above, the Belt of Venus was photographed above morning fog in the Valley of the Moon, a famous wine-producing region in northern California, USA. The belt is frequently caught by accident in other photographs.

June 5, 2013

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Except for the rings of Saturn, the Ring Nebula (M57) is probably the most famous celestial band. Its classic appearance is understood to be due to our own perspective, though. The recent mapping of the expanding nebula's 3-D structure, based in part on this clear Hubble image, indicates that the nebula is a relatively dense, donut-like ring wrapped around the middle of a football-shaped cloud of glowing gas. The view from planet Earth looks down the long axis of the football, face-on to the ring. Of course, in this well-studied example of a planetary nebula, the glowing material does not come from planets. Instead, the gaseous shroud represents outer layers expelled from the dying, once sun-like star, now a tiny pinprick of light seen at the nebula's center. Intense ultraviolet light from the hot central star ionizes atoms in the gas. In the picture, the blue color in the center is ionized helium, the cyan color of the inner ring is the glow of hydrogen and oxygen, and the reddish color of the outer ring is from nitrogen and sulfur. The Ring Nebula is about one light-year across and 2,000 light-years away.

June 4, 2013

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Few astronomical sights excite the imagination like the nearby stellar nursery known as the Orion Nebula. The Nebula's glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud. Many of the filamentary structures visible in the above image are actually shock waves - fronts where fast moving material encounters slow moving gas. The Orion Nebula spans about 40 light years and is located about 1500 light years away in the same spiral arm of our Galaxy as the Sun. The Great Nebula in Orion can be found with the unaided eye just below and to the left of the easily identifiable belt of three stars in the popular constellation Orion. The above image shows the nebula in three colors specifically emitted by hydrogen, oxygen, and sulfur gas. The whole Orion Nebula cloud complex, which includes the Horsehead Nebula, will slowly disperse over the next 100,000 years.

June 3, 2013

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Could life ever have existed on Mars? To help find out, humanity landed the Curiosity rover on Mars last August. To make sure the car-sized explorer survived the interplanetary trip and dramatic landing intact, the above image and others was taken peering at, under, and around Curiosity. Pictured above in this unusual vista are three of Curiosity's six wheels, each measuring about half a meter across. In recent months, Curiosity has been exploring the surroundings of an area dubbed Yellowknife Bay. Analyses of data taken by Curiosity's cameras and onboard laboratories has provided strong new evidence that Mars could once have supported life. In the distance is part of the slope to the central peak inside Gale Crater that Curiosity is scheduled to attempt to climb - Mt. Sharp.

June 2, 2013

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What kind of cloud is this? A roll cloud. These rare long clouds may form near advancing cold fronts. In particular, a downdraft from an advancing storm front can cause moist warm air to rise, cool below its dew point, and so form a cloud. When this happens uniformly along an extended front, a roll cloud may form. Roll clouds may actually have air circulating along the long horizontal axis of the cloud. A roll cloud is not thought to be able to morph into a tornado. Unlike a similar shelf cloud, a roll cloud, a type of Arcus cloud, is completely detached from their parent cumulonimbus cloud. Pictured above, a roll cloud extends far into the distance in 2009 January above Las Olas Beach in Maldonado, Uruguay.

June 1, 2013

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Last night, a powerful interplanetary shockwave from the sun slammed the planet and resulted in a G2-class (Kp=6) geomagnetic storm. The storm as of this post still has not let up, but at its peak from last night, it was easily visible as far south as Colorado, Maryland, Iowa, Wisconsin, and Nebraska. High-latitude sky watchers should remain alert for auroras tonight as Earth's magnetic field continues to reverberate from the impact. Today's photograph was taken by Bob Conzemius on June 1, 2013 at Grand Rapids, MN, USA. The powerful green auroras were luminescent enough to penetrate through a thin layer of clouds and create an eerie green skyscape, complemented by the yellow lights of nearby towns. ISO 800, f2.8, 25 sec., 24mm, looking east along the cloud-obscured oval was the specifications for this photo.

May 31, 2013

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As planet Earth approached the plane of the Comet PanSTARRS (C/2011 L4) orbit on May 23rd, comet watchers were treated to this view of its magnificent anti-tail. The long, narrow anti-tail stretches to the right across this frame for nearly 7 degrees or about 14 times the angular size of the full Moon. Dust forming the anti-tail trails along the comet's orbit as it leaves the inner solar system behind. An almost edge-on perspective from near the outbound comet's orbital plane enhances the view of the anti-tail and makes it seem to point in the sunward direction, only apparently contrary to the behavior of comet dust tails pushed outward by the pressure of sunlight. Sweeping far north in planet Earth's skies, the comet is up all night for most of the northern hemisphere, but now bright moonlight interferes with its visibility. PanSTARRS anti-tail is one of the longest since the appearance of Comet Arend-Roland in 1957.

May 30, 2013

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The 16th century Portuguese navigator Ferdinand Magellan and his crew had plenty of time to study the southern sky during the first circumnavigation of planet Earth. As a result, two fuzzy cloud-like objects easily visible to southern hemisphere skygazers are known as the Clouds of Magellan, now understood to be satellite galaxies of our much larger, spiral Milky Way galaxy. About 160,000 light-years distant in the constellation Dorado, the Large Magellanic Cloud (LMC) is seen here in a remarkably deep, colorful, and annotated composite image. Spanning about 15,000 light-years or so, it is the most massive of the Milky Way's satellite galaxies and is the home of the closest supernova in modern times, SN 1987A. The prominent patch just left of center is 30 Doradus, also known as the magnificent Tarantula Nebula, is a giant star-forming region about 1,000 light-years across.

May 29, 2013

Source: My Camera
How bright is nebulosity in Algonquin Park? The answer is its about as bright as it ever gets from the vantage point of this planet. Today's picture is a shot of a pair of nebulae that to my eyes only appeared to be dark fuzzy patches in the sky - I wasn't originally targetting the pair that can be found at the top and bottom of the image but rather I happened to point my camera in this direction while making a larger panorama sized picture. The human eye can't see more than visible light, so many of the nebulae will appear as gray patches. The other reason for this is that they are simply too faint to show colour as well, but a decent camera today will be able to pick them up. A nebula that comes out as a fluorescent violet is likely to have more colour spectra with a wavelength shorter than that of the violet colour spectrum. For this particular nebula, if you had a filter that blocked out all light except ultra Violet, you'd actually get a better picture than one that allows visible light! The following picture highlights the striking difference between infrared, visible and UV filters. Note how the colours of the orion nebula are more vibrant in UV, however the flame nebula near the top left of the image appears invisible in UV - This is because the flame nebula is orange-reddish in colour and is nowhere near the UV spectrum.



May 28, 2013

Source: My Camera
What does the Andromeda Galaxy look like in a sky with no light pollution? M31 is almost impossible to spot in a city or large town, and to the untrained eye can also be difficult when a bright moon fills the sky. However when there's no moon lighting up the sky, you may begin to notice a sizeable fuzzy patch in the constellation of Andromeda, just beside Perseus. This fuzzy patch is the Andromeda Galaxy. It's approximately 2.5 million light years from Earth, however that number will shrink in time. M31 is on a collision course with the Milky Way that will lead to a head on collision in about 2 billion years. While this sounds violent, it is unlikely in this collision that any stars will actually crash into each other. Familiar stars however, will be thrown out of their current position and hurled to various new spots of the galaxy.

May 27, 2013

Source: My Camera
On May 26, 2013, Mercury, Venus and Jupiter formed a very tight triangle, just 2½° wide. The triple conjunction itself is set to last for a span of a couple weeks where all three planets fit inside a 5° circle, but yesterday was the day where all three were closest together. Venus and Mercury, the two right planets in this image, appear their closest together tomorrow May 28. This image was taken atop Leaside Bridge in Toronto, with a hydrofield in the distance. Jupiter continues to sink lower into the horizon while Venus and Mercury make their way higher into better seeing conditions. Mercury is the fastest changing of the three planets, largely because its year is only 88 days and it does not take very long to revolve around the sun. If you follow Mercury long enough, you will begin to see Mercury arc back downward toward the horizon as it heads for another revolution around the sun.

May 26, 2013

Source: My Camera
If you are in a dark location and you are willing to stay up to roughly midnight at this time of year, you have the luxury to step outside on a clear night and enjoy the rise of the milky way - the galaxy that rests in our backyard. Scorpius is the constellation that appears to pull the galactic centre with Antares being the dominant red star in the middle of the constellation. Ophiuchus sits on top of this image above Scorpius, and the Sagittarius Teapot sits above the treeline. Multiple messier objects appear in this image as well including the Trifid and Lagoon nebula.

May 25, 2013

Source: My Camera
So far, Sunspot AR1748 has produced more X-flares than every other sunspot of the past year combined. AR1748 has produced more X-flares than every other sunspot of the past year combined. In summary, AR1748 has given us an X1.7-class flare (0217 UT on May 13), an X2.8-class flare (1609 UT on May 13), an X3.2-class flare (0117 UT on May 14), and an X1-class flare (0152 on May 15). The last of these flares was hurled towards Earth and is the reason I was able to capture the massive geomagnetic storm that occurred over the weekend. While green is the most dominant colour of auroras, with stronger storms you're just as likely to find fainter, purple-blue-red colours as well. Today's picture highlights just how bright and elevated the Northern Lights can get even as low as 45.5842° N. In this picture, the auroras fill over 15° of the northern sky in a spectacular array of colours. While pretty to look at, it's also a reminder that the Earth is constantly bombarded by harmful rays of the sun and a very thin layer is all the planet has to protect those rays from entering the planet and disrupting electronics.

May 24, 2013

Source: My Camera
The Lake of Two Rivers in Algonquin Park was the benefactor of a large geomagnetic storm for those who were willing to look up. The storm came from an x-class solar flare that ejected out of the sun towards Earth on May 15th. At times, the auroras were luminescent enough to be seen inside cars. The auroras for the most part lasted the entire night and continued into the morning hours after sunrise - though by then, they were no longer visible. Purple auroras can be easily seen in this picture. Purple, Blue, Red and green are common colours of auroras where green is the lowest altitude, followed by purple, blue, and then red.

May 23, 2013

Source: My Camera
This scene is found on the west beach on the Lake of Two Rivers in Algonquin Park. A canoe marks the foreground of the lake which has been cast an eerie green glow due to the northern lights roaming around in the distance. Also, a car drove by on the nearby highway whose headlights illuminated the midnight forest to create an intresting depth of field. There was no wind this night, and the water was perfectly still. It acted as if it was a mirror into the sky. The Northern Lights were caused by a geomagnetic storm that hit the earth May 17, 2013 due to an x-class flare that launched from the sun on May 15.

May 22, 2013

Source: My Camera
Your cosmic tea is ready, straight from the celestial teapot with a dash of milk from our local milky way. Enjoy - it's out of this world! This stellar scene is just one of many that laid before me during my trek to Algonquin Park. The teapot of Sagittarius is easily visible, which appears to dip ever so slightly into the Sagittarius cloud, one of the brightest bands of the galactic core that we can see. The Trifid nebula is easily visible to the upper right of the Teapot.

May 21, 2013

[img]http://apod.nasa.gov/apod/image/1305/panstarrs15may2013-mfulle_1368632878_1000.jpg]/img]

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Once the famous sunset comet, PanSTARRS (C/2011 L4) is now visible all night from much of the northern hemisphere, bound for the outer solar system as it climbs high above the ecliptic plane. Dimmer and fading, the comet's broad dust tail is still growing, though. This widefield telescopic image was taken against the starry background of the constellation Cepheus on May 15. It shows the comet has developed an extensive anti-tail, dust trailing along the comet's orbit (to the left of the coma), stretching more than 3 degrees across the frame. Since the comet is just over 1.6 astronomical units from planet Earth, that corresponds to a distance of over 12 million kilometers. In late May Comet PanSTARRS will pass within a few degrees of the north celestial pole.

May 20, 2013

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One of the brightest galaxies in planet Earth's sky and similar in size to the Milky Way, big, beautiful spiral M81 lies 11.8 million light-years away in the northern constellation Ursa Major. This deep image of the region reveals details in the bright yellow core, but at the same time follows fainter features along the galaxy's gorgeous blue spiral arms and sweeping dust lanes. It also follows the expansive, arcing feature, known as Arp's loop, that seems to rise from the galaxy's disk at the right. Studied in the 1960s, Arp's loop has been thought to be a tidal tail, material pulled out of M81 by gravitational interaction with its large neighboring galaxy M82. But a recent investigation demonstrates that much of Arp's loop likely lies within our own galaxy. The loop's colors in visible and infrared light match the colors of pervasive clouds of dust, relatively unexplored galactic cirrus only a few hundred light-years above the plane of the Milky Way. Along with the Milky Way's stars, the dust clouds lie in the foreground of this remarkable view. M81's dwarf companion galaxy, Holmberg IX, can be seen just above and left of the large spiral. On the sky, this image spans about 0.5 degrees, about the size of the Full Moon.

May 19, 2013

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Scroll right to take in the view from the highest summit in the contiguous USA. The above 360-degree digitally stitched panorama, taken in mid-July, shows the view from 4,400-meter high Mt. Whitney in Sequoia National Park, California. In the foreground, angular boulders populate Mt. Whitney's summit while in the distance, just below the horizon, peaks from the Sierra Nevada mountain range are visible. Sky sights include light pollution emanating from Los Angeles and Fresno, visible just above the horizon. Dark clouds, particularly evident on the image left well above the horizon, are the remnants of a recent thunderstorm near Death Valley. High above, the band of the Milky Way Galaxy arches across the image left. Bright airglow bands are visible all over the sky but are particularly prominent on the image right. The planet Jupiter appears as the brightest point on the image left. A discerning eye can also find a faint image of the far distant Andromeda galaxy, a satellite trail, and many constellations.

May 18, 2013

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The Parkes 64 meter radio telescope is known for its contribution to human spaceflight, famously supplying television images from the Moon to denizens of planet Earth during Apollo 11. The enormous, steerable, single dish looms in the foreground of this early evening skyscape. Above it, the starry skies of New South Wales, Australia include familiar southerly constellations Vela, Puppis, and Hydra along with a sight that will never be seen again. Still glinting in sunlight and streaking right to left just below the radio telescope's focus cabin, the space shuttle orbiter Atlantis has just undocked with the International Space Station for the final time. The space station itself follows arcing from the lower right corner of the frame, about two minutes behind Atlantis in low Earth orbit. Atlantis made its final landing early July 21, 5:57am EDT at NASA's Kennedy Space Center.

May 17, 2013

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Above this boreal landscape, the arc of the Milky Way and shimmering aurorae flow through the night. Like an echo, below them lies Iceland's spectacular Godafoss, the Waterfall of the Gods. Shining just below the Milky Way, bright Jupiter is included in the panoramic nightscape recorded on March 9. Faint and diffuse, the Andromeda Galaxy (M31) appears immersed in the auroral glow. The digital stitch of four frames is a first place winner in the 2013 International Earth and Sky Photo Contest on Dark Skies Importance organized by The World at Night. An evocative record of the beauty of planet Earth's night sky, all the contest's winning entries are featured in this video. http://vimeo.com/41781867

May 16, 2013

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Swinging around the Sun's eastern limb on Monday, a group of sunspots labeled active region AR1748 has produced the first four X-class solar flares of 2013 in less than 48 hours. In time sequence clockwise from the top left, flashes from the four were captured in extreme ultraviolet images from the Solar Dynamics Observatory. Ranked according to their peak brightness in X-rays, X-class flares are the most powerful class and are frequently accompanied by coronal mass ejections (CMEs), massive clouds of high energy plasma launched into space. But CMEs from the first three flares were not Earth-directed, while one associated with the fourth flare may deliver a glancing blow to the Earth's magnetic field on May 18. Also causing temporary radio blackouts, AR1748 is likely not finished. Still forecast to have a significant chance of producing strong flares, the active region is rotating into more direct view across the Sun's nearside.

May 15, 2013

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What caused this mess? Some type of star exploded to create the unusually shaped nebula known as Kepler's supernova remnant, but which type? Light from the stellar explosion that created this energized cosmic cloud was first seen on planet Earth in October 1604, a mere four hundred years ago. The supernova produced a bright new star in early 17th century skies within the constellation Ophiuchus. It was studied by astronomer Johannes Kepler and his contemporaries, without the benefit of a telescope, as they searched for an explanation of the heavenly apparition. Armed with a modern understanding of stellar evolution, early 21st century astronomers continue to explore the expanding debris cloud, but can now use orbiting space telescopes to survey Kepler's supernova remnant (SNR) across the spectrum. Recent X-ray data and images of Kepler's supernova remnant taken by the orbiting Chandra X-ray Observatory has shown relative elemental abundances typical of a Type Ia supernova, and further indicated that the progenitor was a white dwarf star that exploded when it accreted too much material from a companion Red Giant star and went over Chandrasekhar's limit. About 13,000 light years away, Kepler's supernova represents the most recent stellar explosion seen to occur within our Milky Way galaxy.

May 14, 2013

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What happens when two galaxies collide? Although it may take over a billion years, such titanic clashes are quite common. Since galaxies are mostly empty space, no internal stars are likely to themselves collide. Rather the gravitation of each galaxy will distort or destroy the other galaxy, and the galaxies may eventually merge to form a single larger galaxy. Expansive das and dust clouds collide and trigger waves of star formation that complete even during the interaction process. Pictured above is a computer simulation of two large spiral galaxies colliding, interspersed with real still images taken by the Hubble Space Telescope. Our own Milky Way Galaxy has absorbed several smaller galaxies during its existence and is even projected to merge with the larger neighboring Andromeda galaxy in a few billion years.

May 13, 2013

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It was just eight minutes after sunrise, last week, and already there were four things in front of the Sun. The largest and most notable was Earth's Moon, obscuring a big chunk of the Sun's lower limb as it moved across the solar disk, as viewed from Fremantle, Australia. This was expected as the image was taken during a partial solar eclipse - an eclipse that left sunlight streaming around all sides of the Moon from some locations. Next, a band of clouds divided the Sun horizontally while showing interesting internal structure vertically. The third intervening body might be considered to be the Earth's atmosphere, as it dimmed the Sun from its higher altitude brightness while density fluctuations caused the Sun's edges to appear to shimmer. Although closest to the photographer, the least expected solar occulter was an airplane. Quite possibly, passengers on both sides of that airplane were contemplating the unusual view only visible out the eastern-facing windows.

May 12, 2013

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Sometimes the sky above can become quite a show. In early September of 2010, for example, the Moon and Venus converged, creating quite a sight by itself for sky enthusiasts around the globe. From some locations, though, the sky was even more picturesque. In the above image taken last week from Spain, a crescent Moon and the planet Venus, on the far right, were captured during sunset posing against a deep blue sky. In the foreground, dark storm clouds loom across the image bottom, while a white anvil cloud shape appears above. Black specks dot the frame, caused by a flock of birds taking flight. Very soon after this picture was taken, however, the birds passed by, the storm ended, and Venus and the Moon set. Bright Venus again becomes visible just after sunset this 2013 May and will appear near Jupiter toward the end of the month.

May 11, 2013

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This week the shadow of the New Moon fell on planet Earth, crossing Queensland's Cape York in northern Australia ... for the second time in six months. On the morning of May 10, the Moon's apparent size was too small to completely cover the Sun though, revealing a "ring of fire" along the central path of the annular solar eclipse. Near mid-eclipse from Coen, Australia, a webcast team captured this telescopic snapshot of the annular phase. Taken with a hydrogen-alpha filter, the dramatic image finds the Moon's silhouette just within the solar disk, and the limb of the active Sun spiked with solar prominences. Still, after hosting back-to-back solar eclipses, northern Australia will miss the next and final solar eclipse of 2013. This November, a rare hybrid eclipse will track across the North Atlantic and equatorial Africa.

May 10, 2013

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Face-on spiral galaxy M77 lies a mere 47 million light-years away toward the aquatic constellation Cetus. At that estimated distance, the gorgeous island universe is about 100 thousand light-years across. Also known as NGC 1068, its compact and very bright core is well studied by astronomers exploring the mysteries of supermassive black holes in active Seyfert galaxies. M77 is also seen at x-ray, ultraviolet, infrared, and radio wavelengths. But this sharp visible light image based on Hubble data follows its winding spiral arms traced by obscuring dust clouds and red-tinted star forming regions close in to the galaxy's luminous core.

May 9, 2013

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As the New Moon continues this season's celestial shadow play, an annular solar eclipse track begins in western Australia at 22:30 UT on May 9 - near sunrise on May 10 local time. Because the eclipse occurs within a few days of lunar apogee, the Moon's silhouette does not quite cover the Sun during mid-eclipse, momentarily creating a spectacular ring of fire. While a larger region witnesses a partial eclipse, the annular mid-eclipse phase is visible along a shadow track only about 200 kilometers wide but 13,000 kilometers long, extending across the central Pacific. For given locations along it, the ring of fire lasts from 4 to 6 minutes. Near the horizon, the appearance of the May 9/10 annular eclipse (online viewing) is suggested by this dramatic composite from May of 2012. The timelapse sequence depicts an annular eclipse in progress before sunset over Monument Valley in the southwestern United States.

May 8, 2013

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A tremendous explosion has occurred in the nearby universe and major telescopes across Earth and space are investigating. Dubbed GRB 130427A, the gamma-ray burst was first detected by the Earth-orbiting Fermi and Swift satellites observing at high energies and quickly reported down to Earth. Within three minutes, the half-meter ISON telescope in New Mexico found the blast in visible light, noted its extreme brightness, and relayed more exact coordinates. Within the next few minutes, the bright optical counterpart was being tracked by several quickly re-pointable telescopes including the 2.0-meter P60 telescope in California, the 1.3-meter PAIRITEL telescope in Arizona, and the 2.0-meter Faulkes Telescope North in Hawaii. Within two hours, the 8.2-meter Gemini North telescope in Hawaii noted a redshift of 0.34, placing the explosion about 5 billion light years away - considered nearby in cosmological terms. Previously recorded images from the RAPTOR full-sky monitors were scanned and a very bright optical counterpart - magnitude 7.4 - was found 50 seconds before the Swift trigger. The brightest burst in recent years, a signal from GRB 130427A has also been found in low energy radio waves by the Very Large Array (VLA) and at the highest energies ever recorded by the Fermi satellite. Neutrino, gravitational wave, and telescopes designed to detect only extremely high energy photons are checking their data for a GRB 130427A signal. Pictured in the above animation, the entire gamma-ray sky is shown becoming momentarily dominated by the intense glow of GRB 130427A. Continued tracking the optical counterpart will surely be ongoing as there is a possibility that the glow of a classic supernova will soon emerge.

May 7, 2013

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To see a vista like this takes patience, hiking, and a camera. Patience was needed in searching out just the right place and waiting for just the right time. A short hike was needed to reach this rugged perch above a secluded cove in Julia Pfeiffer Burns State Park in California, USA. And a camera was needed for the long exposure required to bring out the faint light from stars and nebula in the background Milky Way galaxy. Moonlight and a brief artificial flash illuminated the hidden beach and inlet behind nearby trees in the above composite image taken about two weeks ago. Usually obscured McWay Falls is visible just below the image center, while the Pacific Ocean is in view to its right.

May 6, 2013

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What caused the interestingly intricate tails that Comet Lemmon displayed earlier this year? First of all, just about every comet that nears the Sun displays two tails: a dust tail and an ion tail. Comet Lemmon's dust tail, visible above and around the comet nucleus in off-white, is produced by sun-light reflecting dust shed by the comet's heated nucleus. Flowing and more sculptured, however, is C/2012 F6 (Lemmon)'s blue ion tail, created by the solar wind pushing ions expelled by the nucleus away from the Sun. Also of note is the coma seen surrounding Comet Lemmon's nucleus, tinted green by atomic carbon gas fluorescing in sunlight. The above image was taken from the dark skies of Namibia in mid-April. Comet Lemmon is fading as it now heads back to the outer Solar System.

May 5, 2013

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Is that a spaceship or a cloud? Although it may seem like an alien mothership, it's actually a impressive thunderstorm cloud called a supercell. Such colossal storm systems center on mesocyclones - rotating updrafts that can span several kilometers and deliver torrential rain and high winds including tornadoes. Jagged sculptured clouds adorn the supercell's edge, while wind swept dust and rain dominate the center. A tree waits patiently in the foreground. The above supercell cloud was photographed in July west of Glasgow, Montana, USA, caused minor damage, and lasted several hours before moving on.

May 4, 2013

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Last week, as the Sun set a Full Moon rose over the springtime landscape of Tihany, Hungary on the northern shores of Lake Balaton. As it climbed into the clear sky, the Moon just grazed the dark, umbral shadow of planet Earth in the year's first partial lunar eclipse. The partial phase, seen near the top of this frame where the lunar disk is darkened along the upper limb, lasted for less than 27 minutes. Composited from consecutive exposures, the picture presents the scene's range of natural colors and subtle shading apparent to the eye. At next week's New Moon, the season's celestial shadow play will continue with an annular solar eclipse, the path of annularity tracking through northern Australia and the central Pacific.

May 3, 2013

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Combined image data from the massive, ground-based VISTA telescope and the Hubble Space Telescope was used to create this wide perspective of the interstellar landscape surrounding the famous Horsehead Nebula. Captured at near-infrared wavelengths, the region's dusty molecular cloud sprawls across the scene that covers an angle about two-thirds the size of the Full Moon on the sky. Left to right the frame spans just over 10 light-years at the Horsehead's estimated distance of 1,600 light-years. Also known as Barnard 33, the still recognizable Horsehead Nebula stands at the upper right, the near-infrared glow of a dusty pillar topped with newborn stars. Below and left, the bright reflection nebula NGC 2023 is itself the illuminated environs of a hot young star. Dense clouds below the base of the Horsehead and on the outskirts of NGC 2023 show the tell-tale far red emission of energetic jets, known as Herbig-Haro objects, also associated with newborn stars.

May 2, 2013

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Acquiring its first sunlit views of far northern Saturn late last year, the Cassini spacecraft's narrow-angle camera recorded this stunning image of the vortex at the ringed planet's north pole. The false color, near-infrared image results in red hues for low clouds and green for high ones, causing the north-polar hurricane to take on the appearance of a rose. Enormous by terrestrial hurricane standards, this storm's eye is about 2,000 kilometers wide, with clouds at the outer edge traveling at over 500 kilometers per hour. The north pole Saturn hurricane swirls inside the large, six-sided weather pattern known as the hexagon. Of course, in 2006 Cassini also imaged the hurricane at Saturn's south pole.

May 1, 2013

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This huge ball of stars predates our Sun. Long before humankind evolved, before dinosaurs roamed, and even before our Earth existed, ancient globs of stars condensed and orbited a young Milky Way Galaxy. Of the 200 or so globular clusters that survive today, Omega Centauri is the largest, containing over ten million stars. Omega Centauri is also the brightest globular cluster, at apparent visual magnitude 3.9 it is visible to southern observers with the unaided eye. Cataloged as NGC 5139, Omega Centauri is about 18,000 light-years away and 150 light-years in diameter. Unlike many other globular clusters, the stars in Omega Centauri show several different ages and trace chemical abundances, indicating that the globular star cluster has a complex history over its 12 billion year age.

April 30, 2013

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What spacecraft is humanity currently using to explore our Solar System? Presently, every inner planet has at least one robotic explorer, while several others are monitoring our Sun, some are mapping Earth's Moon, a few are chasing asteroids and comets, one is orbiting Saturn, and several are even heading out into deep space. The above illustration gives more details, with the inner Solar System depicted on the upper right and the outer Solar System on the lower left. Given the present armada, our current epoch might become known as the time when humanity first probed its own star system. Sometimes widely separated spacecraft act together as an InterPlanetary Network to determine the direction of distant explosions by noting when each probe detects high energy photons. Future spacecraft milestones, as indicated along the bottom of the graphic, include Dawn reaching Ceres, the largest object in the asteroid belt, and New Horizons reaching Pluto, both in 2015.

April 29, 2013

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What's that next to the Milky Way? An unusual natural rock formation known as Roque Cinchado or Stone Tree found on the Spanish Canary Island of Tenerife. A famous icon, Roque Cinchado is likely a dense plug of cooled volcanic magma that remains after softer surrounding rock eroded away. Majestically, the central band of our Milky Way Galaxy is visible arcing across the right of the above seven image panoramic mosaic taken during the summer of 2010. On the far right is the Teide volcano complete with a lenticular cloud hovering near its peak.

April 28, 2013

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It was one of the largest and longest lived storms ever recorded in our Solar System. First seen in late 2010, the above cloud formation in the northern hemisphere of Saturn started larger than the Earth and soon spread completely around the planet. The storm was tracked not only from Earth but from up close by the robotic Cassini spacecraft currently orbiting Saturn. Pictured above in false colored infrared in February, orange colors indicate clouds deep in the atmosphere, while light colors highlight clouds higher up. The rings of Saturn are seen nearly edge-on as the thin blue horizontal line. The warped dark bands are the shadows of the rings cast onto the cloud tops by the Sun to the upper left. A source of radio noise from lightning, the intense storm was thought to relate to seasonal changes when spring emerges in the north of Saturn. After raging for over six months, the iconic storm circled the entire planet and then tried to absorb its own tail - which surprisingly caused it to fade away.

This set of images from NASA's Cassini mission shows the evolution of a massive thunder-and-lightning storm that circled all the way around Saturn and fizzled when it ran into its own tail. The storm was first detected on Dec. 5, 2010.


April 27, 2013

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Get out your red/blue glasses and gaze across the floor of Gale crater on Mars. From your vantage point on the deck of the Curiosity Rover Mount Sharp, the crater's 5 kilometer high central mountain looms over the southern horizon. Poised in the foreground is the rover's robotic arm with tool turret extended toward the flat veined patch of martian surface dubbed "John Klein". A complete version of the stereo view spans 360 degrees, digitally stitched together from the rover's left and right navigation camera frames taken in late January. The layered lower slopes of Mount Sharp, formally known as Aeolis Mons, are a future destination for Curiosity. Find the complete version here: http://photojournal.jpl.nasa.gov/catalog/PIA16925

April 26, 2013

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Our solar system's miasma of incandescent plasma, the Sun may look a little scary here. The picture is a composite of 25 images recorded in extreme ultraviolet light by the orbiting Solar Dynamics Observatory between April 16, 2012 and April 15, 2013. The particular wavelength of light, 171 angstroms, shows emission from highly ionized iron atoms in the solar corona at a characteristic temperatures of about 600,000 kelvins (about 1 million degrees F). Girdling both sides of the equator during the approach to maximum in its 11-year solar cycle, the solar active regions are laced with bright loops and arcs along magnetic field lines. Of course, a more familiar visible light view would show the bright active regions as groups of dark sunspots. Three years of Solar Dynamics Observatory images are compressed into this short video.

April 25, 2013

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The dark, inner shadow of planet Earth is called the umbra. Shaped like a cone extending into space, it has a circular cross section and is most easily seen during a lunar eclipse. But the complete cross section is larger than the Moon's angular size in the stages of an eclipse. Still, this thoughtful composite illustrates the full extent of the circular shadow by utilizing images from both partial and total eclipses passing through different parts of the umbra. The images span the years 1997 to 2011, diligently captured with the same optics, from Voronezh, Russia. Along the bottom and top are stages of the partial lunar eclipses from September 2006 and August 2008 respectively. In the rightside bottom image, the Moon is entering the umbra for the total eclipse of September 1997. At left bottom, the Moon leaves the umbra after totality in May 2004. Middle right, center, and left, are stages of the total eclipse of June 2011, including the central, deep red total phase. During today's brief partial lunar eclipse seen only from the eastern hemisphere, the Moon will just slightly graze the umbra's lower edge.

April 24, 2013

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What happens if you wring out a wet towel while floating in space? The water shouldn't fall toward the floor because while orbiting the Earth, free falling objects will appear to float. But will the water fly out from the towel, or what? The answer may surprise you. To find out and to further exhibit how strange being in orbit can be, Expedition 35 Commander Chris Hadfield did just this experiment last week in the microgravity of the Earth orbiting International Space Station. As demonstrated in the above video, although a few drops do go flying off, most of the water sticks together and forms a unusual-looking cylindrical sheath in and around the towel. The self-sticking surface tension of water is well known on Earth, for example being used to create Artistic Water cascades and, more generally, raindrops.

April 23, 2013

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What looks like a puff-ball is surely the remains of the brightest supernova in recorded human history. In 1006 AD, it was recorded as lighting up the nighttime skies above areas now known as China, Egypt, Iraq, Italy, Japan, and Switzerland. The expanding debris cloud from the stellar explosion, found in the southerly constellation the Wolf (Lupus), still puts on a cosmic light show across the electromagnetic spectrum. In fact, the above image results from three colors of X-rays taken by the orbiting Chandra X-ray Observatory. Now known as the SN 1006 supernova remnant, the debris cloud appears to be about 60 light-years across and is understood to represent the remains of a white dwarf star. Part of a binary star system, the compact white dwarf gradually captured material from its companion star. The buildup in mass finally triggered a thermonuclear explosion that destroyed the dwarf star. Because the distance to the supernova remnant is about 7,000 light-years, that explosion actually happened 7,000 years before the light reached Earth in 1006. Shockwaves in the remnant accelerate particles to extreme energies and are thought to be a source of the mysterious cosmic rays.

April 22, 2013

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While drifting through the cosmos, a magnificent interstellar dust cloud became sculpted by stellar winds and radiation to assume a recognizable shape. Fittingly named the Horsehead Nebula, it is embedded in the vast and complex Orion Nebula (M42). A potentially rewarding but difficult object to view personally with a small telescope, the above gorgeously detailed image was recently taken in infrared light by the orbiting Hubble Space Telescope in honor of the 23rd anniversary of Hubble's launch. The dark molecular cloud, roughly 1,500 light years distant, is cataloged as Barnard 33 and is seen above primarily because it is backlit by the nearby massive star Sigma Orionis. The Horsehead Nebula will slowly shift its apparent shape over the next few million years and will eventually be destroyed by the high energy starlight.

April 21, 2013

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Do you see it? This common question frequently precedes the rediscovery of one of the most commonly recognized configurations of stars on the northern sky: the Big Dipper. This grouping of stars is one of the few things that has likely been seen, and will be seen, by every generation. The Big Dipper is not by itself a constellation. Although part of the constellation of the Great Bear (Ursa Major), the Big Dipper is an asterism that has been known by different names to different societies. Five of the Big Dipper stars are actually near each other in space and were likely formed at nearly the same time. Connecting two stars in the far part of the Big Dipper will lead one to Polaris, the North Star, which is part of the Little Dipper. Relative stellar motions will cause the Big Dipper to slowly change its apparent configuration over the next 100,000 years.

April 20, 2013

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As far as the eye could see, it was a dark night at Las Campanas Observatory in the southern Atacama desert of Chile. But near local midnight on April 11, this mosaic of 3 minute long exposures revealed a green, unusually intense, atmospheric airglow stretching over thin clouds. Unlike aurorae powered by collisions with energetic charged particles and seen at high latitudes, the airglow is due to chemiluminescence, the production of light in a chemical reaction, and found around the globe. The chemical energy is provided by the Sun's extreme ultraviolet radiation. Like aurorae, the greenish hue of this airglow does originate at altitudes of 100 kilometers or so dominated by emission from excited oxygen atoms. The gegenschein, sunlight reflected by dust along the solar system's ecliptic plane was still visible on that night, a faint bluish cloud just right of picture center. At the far right, the Milky Way seems to rise from the mountain top perch of the Magellan telescopes. Left are the OGLE project and du Pont telescope domes.

April 19, 2013

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Sculpted by stellar winds and radiation, the star factory known as Messier 17 lies some 5,500 light-years away in the nebula-rich constellation Sagittarius. At that distance, this degree wide field of view spans almost 100 light-years. The sharp, composite, color image utilizing data from space and ground based telescopes, follows faint details of the region's gas and dust clouds against a backdrop of central Milky Way stars. Stellar winds and energetic light from hot, massive stars formed from M17's stock of cosmic gas and dust have slowly carved away at the remaining interstellar material producing the cavernous appearance and undulating shapes. M17 is also known as the Omega Nebula or the Swan Nebula.

April 18, 2013

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What kind of cloud is next to that mountain? A lenticular. This type of cloud forms in air that passes over a mountain, rises up again, and cools past the dew point -- so what molecular water carried in the air condenses into droplets. The layered nature of some lenticular clouds may make them appear, to some, as large alien spaceships. In this case, the mountain pictured is Mt. Hood located in Oregon, USA. Lenticular clouds can only form when conditions are right - for example this is first time this astrophotographer has seen a lenticular cloud at night near Mt. Hood. The above image was taken in mid-March about two hours before dawn.

April 17, 2013

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An expanded view from yesterday's picture, Large galaxies and faint nebulae highlight this deep image of the M81 Group of galaxies. First and foremost in the wide-angle 12-hour exposure is the grand design spiral galaxy M81, the largest galaxy visible in the image. M81 is gravitationally interacting with M82 just below it, a big galaxy with an unusual halo of filamentary red-glowing gas. Around the image many other galaxies from the M81 Group of galaxies can be seen. Together with other galaxy congregates including our Local Group of galaxies and the Virgo Cluster of galaxies, the M81 Group is part of the expansive Virgo Supercluster of Galaxies. This whole galaxy menagerie is seen through the faint glow of an Integrated Flux Nebula, a little studied complex of diffuse gas and dust clouds in our Milky Way Galaxy.

April 16, 2013

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One of the brightest galaxies in planet Earth's sky is similar in size to our Milky Way Galaxy: big, beautiful M81. This grand spiral galaxy lies 11.8 million light-years away toward the northern constellation of the Great Bear (Ursa Major). The deep image of the region reveals details in the bright yellow core, but at the same time follows fainter features along the galaxy's gorgeous blue spiral arms and sweeping dust lanes. It also follows the expansive, arcing feature, known as Arp's loop, that seems to rise from the galaxy's disk at the upper right. Studied in the 1960s, Arp's loop has been thought to be a tidal tail, material pulled out of M81 by gravitational interaction with its large neighboring galaxy M82. But a subsequent investigation demonstrates that at least some of Arp's loop likely lies within our own galaxy. The loop's colors in visible and infrared light match the colors of pervasive clouds of dust, relatively unexplored galactic cirrus only a few hundred light-years above the plane of the Milky Way. Along with the Milky Way's stars, the dust clouds lie in the foreground of this remarkable view. M81's dwarf companion galaxy, Holmberg IX, can be seen just above the large spiral. On the sky, this image spans about 0.5 degrees, about the size of the Full Moon.

April 15, 2013

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Stars are forming in the Soul of the Queen of Aethopia. More specifically, a large star forming region called the Soul Nebula can be found in the direction of the constellation Cassiopeia, who Greek mythology credits as the vain wife of a King who long ago ruled lands surrounding the upper Nile river. The Soul Nebula houses several open clusters of stars, a large radio source known as W5, and huge evacuated bubbles formed by the winds of young massive stars. Located about 6,500 light years away, the Soul Nebula spans about 100 light years and is usually imaged next to its celestial neighbor the Heart Nebula (IC 1805). The above image appears mostly red due to the emission of a specific color of light emitted by excited hydrogen gas.

April 14, 2013

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Gliding silently through the outer Solar System, the Voyager 2 spacecraft camera captured Neptune and Triton together in crescent phase in 1989. The elegant picture of the gas giant planet and its cloudy moon was taken from behind just after closest approach. It could not have been taken from Earth because Neptune never shows a crescent phase to sunward Earth. The unusual vantage point also robs Neptune of its familiar blue hue, as sunlight seen from here is scattered forward, and so is reddened like the setting Sun. Neptune is smaller but more massive than Uranus, has several dark rings, and emits more light than it receives from the Sun.

April 13, 2013

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This week the Sun gave up its strongest solar flare so far in 2013, accompanied by a coronal mass ejection (CME) headed toward planet Earth. A false-color composite image in extreme ultraviolet light from the Solar Dynamics Observatory captures the moment, recorded on April 11 at 0711 UTC. The flash, a moderate, M6.5 class flare erupting from active region AR 11719, is near the center of the solar disk. Other active regions, areas of intense magnetic fields seen as sunspot groups in visible light, mottle the surface as the solar maximum approaches. Loops and arcs of glowing plasma trace the active regions' magnetic field lines. A massive cloud of energetic, charged particles, the CME will impact the Earth's magnetosphere by this weekend and skywatchers should be on the alert for auroral displays.

April 12, 2013

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On another April 12th, in 1961, Soviet cosmonaut Yuri Alexseyevich Gagarin became the first human to see planet Earth from space. Commenting on his view from orbit he reported, "The sky is very dark; the Earth is bluish. Everything is seen very clearly". On yet another April 12th, in 1981 NASA launched the first space shuttle. To celebrate in 2013, consider this image from the orbiting International Space Station, a stunning view of the planet at night from low Earth orbit. Constellations of lights connecting the densely populated cities along the Atlantic east coast of the United States are framed by two Russian spacecraft docked at the space station. Easy to recognize cities include New York City and Long Island at the right. From there, track toward the left for Philadelphia, Baltimore, and then Washington DC near picture center.

April 11, 2013

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In a haunting vista you can never see, bright stars and the central Milky Way rise over the dark skyline of metropolitan Pudong in Shanghai, China. Looking east across the Huangpu River, the cityscape includes Pudong's 470 meter tall Oriental Pearl Tower. The night sky stretches from Antares and the stars of Scorpius at the far right, to Altair in Aquila at the left. To create the vision of an unseen reality, part of a series of Darkened Cities, photographer Thierry Cohen has combined a daytime image of the city skyline with an image matched in orientation from a dark sky region at the same latitude, just west of Merzouga, Morocco. The result finds the night sky that hours earlier also arced over Shanghai, but drowned in the lights of a city upon the sea.

April 10, 2013

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If you glanced out a side window of the International Space Station, what might you see? If you were Expedition 34 flight engineer Chris Hadfield, and you were looking out one of windows of Japan's Kibo Research Module on February 26, you might have seen the above vista. In the distance lies the darkness of outer space and the blueness of planet Earth. Large ISS objects include long solar panels that stretch diagonally from the upper left and the cylindrical airlock of the Pressurized Module that occupies the lower right. Numerous ports and platforms of the space station are visible and labeled on an annotated companion image. Of particular note is what looks to be a washer - dryer pair toward the image left, which are really NASA's HREP (near) and JAXA's MCE (far) research platforms. The gold foil covered experiment in the rear of HREP is the Remote Atmospheric and Ionospheric Detection System (RAIDS) that monitors atmospheric airglow, while MCE includes the Global Lightning and Sprite Measurements (JEM-GLIMS) instrument that monitors atmospheric electrical discharges. The current Expedition 35 crew is now commanded by Colonel Hadfield and scheduled to stay aboard the space station until May.

April 9, 2013

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It's the dim star, not the bright one, near the center of NGC 3132 that created this odd but beautiful planetary nebula. Nicknamed the Eight-Burst Nebula and the Southern Ring Nebula, the glowing gas originated in the outer layers of a star like our Sun. In this reprocessed color picture, the hot purplish pool of light seen surrounding this binary system is energized by the hot surface of the faint star. Although photographed to explore unusual symmetries, it's the asymmetries that help make this planetary nebula so intriguing. Neither the unusual shape of the surrounding cooler shell nor the structure and placements of the cool filamentary dust lanes running across NGC 3132 are well understood.

April 8, 2013

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How far away is "redshift six"? Although humans are inherently familiar with distance and time, what is actually measured for astronomical objects is redshift, a color displacement that depends on exactly how energy density has evolved in our universe. Now since cosmological measurements in recent years have led to a concordance on what energy forms pervade our universe, it is now possible to make a simple table relating observed cosmological redshift, labeled "z", with standard concepts of distance and time, including the extrapolated time since the universe began. One such table is listed above, where redshift z is listed in the first and last columns, while the corresponding universe age in billions of years is listed in the central column. To find the meaning of the rest of the columns, please read the accompanying technical paper here. Although stars in our galaxy are effectively at cosmological redshift zero, the most distant supernovae seen occur out past redshift one, which the above chart shows occurred when the universe was approximately half its present age. By contrast, the most distant gamma-ray bursts yet observed occur out past redshift six, occurring when the universe was younger than one billion years old, less than 10 percent of its present age.

April 7, 2013

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Just days after sharing the western evening sky with Venus in 2007, the Moon moved on to Saturn - actually passing in front of the ringed planet Saturn when viewed in skies over Europe, northern Africa, and western Asia. Because the Moon and bright planets wander through the sky near the ecliptic plane, such occultation events are not uncommon, but they are dramatic, especially in telescopic views. For example, in this sharp image Saturn is captured emerging from behind the Moon, giving the illusion that it lies just beyond the Moon's bright edge. Of course, the Moon is a mere 400 thousand kilometers away, compared to Saturn's distance of 1.4 billion kilometers. Taken with a digital camera and 20 inch diameter telescope at the Weikersheim Observatory in southern Germany, the picture is a single exposure adjusted to reduce the difference in brightness between Saturn and the cratered lunar surface.

April 6, 2013

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No sudden, sharp boundary marks the passage of day into night in this gorgeous view of ocean and clouds over our fair planet Earth. Instead, the shadow line or terminator is diffuse and shows the gradual transition to darkness we experience as twilight. With the Sun illuminating the scene from the right, the cloud tops reflect gently reddened sunlight filtered through the dusty troposphere, the lowest layer of the planet's nurturing atmosphere. A clear high altitude layer, visible along the dayside's upper edge, scatters blue sunlight and fades into the blackness of space. This picture actually is a single digital photograph taken in June of 2001 from the International Space Station orbiting at an altitude of 211 nautical miles.

April 5, 2013

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It looks like a double comet, but Comet PanSTARRS (C/2011 L4) is just offering skygazers a Messier moment. Outward bound and fading in this starry scene, the well-photographed comet is remarkably similar in brightness to M31, the Andromeda Galaxy. Tracking through northern skies just below the galaxy, the comet was captured as local midnight approached on April 3. Both comet and galaxy were visible to the eye and are immersed in the faint glow of northern lights as our own Milky Way galaxy arcs over a snowy field near Tänndalen, Sweden. Double star cluster h and chi Persei can be spotted along the Milky Way's arc high above the comet/galaxy pair. Follow the arc to bright Deneb, alpha star of the constellation Cygnus, at the right edge of the frame.

April 4, 2013

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This beautiful, bright, spiral galaxy is Messier 64, often called the Black Eye Galaxy or the Sleeping Beauty Galaxy for its heavy-lidded appearance in telescopic views. M64 is about 17 million light-years distant in the otherwise well-groomed northern constellation Coma Berenices. In fact, the Red Eye Galaxy might also be an appropriate moniker in this colorful composition of narrow and wideband images. The enormous dust clouds obscuring the near-side of M64's central region are laced with the telltale reddish glow of hydrogen associated with star forming regions. But they are not this galaxy's only peculiar feature. Observations show that M64 is actually composed of two concentric, counter-rotating systems of stars, one in the inner 3,000 light-years and another extending to about 40,000 light-years and rotating in the opposite direction. The dusty eye and bizarre rotation is likely the result of a billion year old merger of two different galaxies.

April 3, 2013

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Currently, comet PANSTARRS is passing nearly in front of the galaxy Andromeda. Coincidentally, both comet and galaxy appear now to be just about the same angular size. In physical size, even though Comet PANSTARRS is currently the largest object in the Solar System with a tail spanning about 15 times the diameter of the Sun, it is still about 70 billion times smaller than the Andromeda galaxy (M31). The above image was taken a few days ago near Syktyvkar, Russia. As C/2011 L4 (PANSTARRS) on the lower left recedes from the Sun and dims, it is returning to the northerly direction whence it came. When the comet will return is currently unknown.

April 2, 2013

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Do you see the horse's head? What you are seeing is not the famous Horsehead nebula toward Orion but rather a fainter nebula that only takes on a familiar form with deeper imaging. The main part of the above imaged molecular cloud complex is a reflection nebula cataloged as IC 4592. Reflection nebulas are actually made up of very fine dust that normally appears dark but can look quite blue when reflecting the light of energetic nearby stars. In this case, the source of much of the reflected light is a star at the eye of the horse. That star is part of Nu Scorpii, one of the brighter star systems toward the constellation of the Scorpion Scorpius. A second reflection nebula dubbed IC 4601 is visible surrounding two stars on the upper right of the image center.

April 1, 2013

Source: My Camera
While visiting Wasaga Beach for Easter, I couldn't help but notice the remarkably clear weather that lasted the vast bulk of the weekend. On my first night up I decided to camp at the beach from sunset to about 9:30pm. I captured some panoramic sunset shots, as well as close ups of certain constellations such as Orion and Taurus - featuring the Orion Nebula and the Hyades and Pleiades plus Jupiter, moons et al. But what really caught my attention was when I was just about to pack up - a grey cloud spontaneously appeared to the north west, despite the forecasts saying that there shouldn't be any clouds in the sky. So I readied my camera and confirmed my suspicion - the Northern Lights had made their way all the way down to Wasaga Beach, just 150km from Toronto. As a bonus, Comet PANSTARRS is also visible as a badminton-birdie shaped object just above the horizon halfway to centre from the left, as well as the Andromeda Galaxy, M31. The constellation Cassiopeia centres the top of the image.

March 31, 2013

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Some 60 million light-years away in the southerly constellation Corvus, two large galaxies collided. But the stars in the two galaxies cataloged as NGC 4038 and NGC 4039 don't collide in the course of the ponderous, billion year or so long event. Instead, their large clouds of molecular gas and dust do, triggering furious episodes of star formation near the center of the cosmic wreckage. Spanning about 500 thousand light-years, this stunning view also reveals new star clusters and matter flung far from the scene of the accident by gravitational tidal forces. Of course, the visual appearance of the far-flung arcing structures gives the galaxy pair its popular name - The Antennae.

March 30, 2013

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The Cat's Eye Nebula (NGC 6543) is one of the best known planetary nebulae in the sky. Its haunting symmetries are seen in the very central region of this stunning false-color picture, processed to reveal the enormous but extremely faint halo of gaseous material, over three light-years across, which surrounds the brighter, familiar planetary nebula. Made with data from the Nordic Optical Telescope in the Canary Islands, the composite picture shows extended emission from the nebula. Planetary nebulae have long been appreciated as a final phase in the life of a sun-like star. Only much more recently however, have some planetaries been found to have halos like this one, likely formed of material shrugged off during earlier active episodes in the star's evolution. While the planetary nebula phase is thought to last for around 10,000 years, astronomers estimate the age of the outer filamentary portions of this halo to be 50,000 to 90,000 years.

March 29, 2013

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Orbiting in the plane of Saturn's rings, Saturnian moons have a perpetual ringside view of the gas giant planet. Of course, while passing near the ring plane the Cassini spacecraft also shares their stunning perspective. The thin rings themselves slice across the middle of this Cassini snapshot from April 2011. The scene looks toward the dark night side of Saturn, in the frame at the left, and the still sunlit side of the rings from just above the ringplane. Centered, over 1,500 kilometers across, Rhea is Saturn's second largest moon and is closest to the spacecraft, around 2.2 million kilometers away. To Rhea's right, shiny, 500 kilometer diameter Enceladus is about 3 million kilometers distant. Dione, 1,100 miles wide, is 3.1 million miles from Cassini's camera on the left, partly blocked by Saturn's night side.

March 28, 2013

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Bright spiral galaxy NGC 3169 appears to be unraveling in this cosmic scene, played out some 70 million light-years away just below bright star Regulus toward the faint constellation Sextans. Its beautiful spiral arms are distorted into sweeping tidal tails as NGC 3169 (left) and neighboring NGC 3166 interact gravitationally, a common fate even for bright galaxies in the local universe. In fact, drawn out stellar arcs and plumes, indications of gravitational interactions, seem rampant in the deep and colorful galaxy group photo. The picture spans 20 arc minutes, or about 400,000 light-years at the group's estimated distance, and includes smaller, dimmer NGC 3165 at the right. NGC 3169 is also known to shine across the spectrum from radio to X-rays, harboring an active galactic nucleus that is likely the site of a supermassive black hole.

March 27, 2013

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Why is this horizon so colorful? Because, opposite the Sun, it is raining. What is pictured above is actually just a common rainbow. It's uncommon appearance is caused by the Sun being unusually high in the sky during the rainbow's creation. Since every rainbow's center must be exactly opposite the Sun, a high Sun reflecting off of a distant rain will produce a low rainbow where only the very top is visible - because the rest of the rainbow is below the horizon. Furthermore, no two observers can see exactly the same rainbow - every person finds themselves exactly between the Sun and rainbow's center, and every observer sees the colorful circular band precisely 42 degrees from rainbow's center. The above image featuring the Eiffel Tower was taken in Paris, France last week. Although the intermittent thunderstorms lasted for much of the day, the horizon rainbow lasted for only a few minutes.

March 26, 2013

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If not distracted by the picturesque landscape, waterfalls, stars, and auroras, you might be able to find Comet PANSTARRS. The above image, capturing multiple terrestrial and celestial wonders in a single shot, was taken last week in southwest Iceland. The popular Gullfoss waterfalls are pictured under brilliant auroras that followed a M1-class solar flare and powerful Coronal Mass Ejection two days earlier. Give up on locating the comet? Comet PANSTARRS is faintly visible as a light blip just above the horizon toward the left of the above image. The comet remains more directly visible to northern observers with binoculars looking toward the western sky just after sunset. The photographer's website is found here should you wish to see similar photos.

March 25, 2013

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What is our universe made of? To help find out, ESA launched the Planck satellite to map, in unprecedented detail, slight temperature differences on the oldest surface known - the background sky left billions of years ago when our universe first became transparent to light. Visible in all directions, this cosmic microwave background is a complex tapestry that could only show the hot and cold patterns observed were the universe to be composed of specific types of energy that evolved in specific ways. The results, reported last week, confirm again that most of our universe is mostly composed of mysterious and unfamiliar dark energy, and that even most of the remaining matter energy is strangely dark. Additionally, Planck data impressively peg the age of the universe at about 13.81 billion years, slightly older than that estimated by various other means including NASA's WMAP satellite, and the expansion rate at 67.3 (+/- 1.2) km/sec/Mpc, slightly lower than previous estimates. Some features of the above sky map remain unknown, such as why the temperature fluctuations seem to be slightly greater on one half of the sky than the other.

March 24, 2013

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Inside the head of this interstellar monster is a star that is slowly destroying it. The monster, actually an inanimate pillar of gas and dust, measures over a light year in length. The star, not itself visible through the opaque dust, is bursting out partly by ejecting energetic beams of particles. Similar epic battles are being waged all over the star-forming Carina Nebula (NGC 3372). The stars will win in the end, destroying their pillars of creation over the next 100,000 years, and resulting in a new open cluster of stars. The pink dots are newly formed stars that have already been freed from their birth monster. The above image is only a small part of a highly detailed panoramic mosaic of the Carina Nebula taken by the Hubble Space Telescope in 2007. The technical name for the stellar jets are Herbig-Haro objects. How a star creates Herbig-Haro jets is an ongoing topic of research, but it likely involves an accretion disk swirling around a central star. A second impressive Herbig-Haro jet is visible across the bottom.

March 23, 2013

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Cosmic dust clouds ripple across this infrared portrait of our Milky Way's satellite galaxy, the Large Magellanic Cloud. In fact, the remarkable composite image from the Herschel Space Observatory and the Spitzer Space Telescope show that dust clouds fill this neighboring dwarf galaxy, much like dust along the plane of the Milky Way itself. The dust temperatures tend to trace star forming activity. Spitzer data in blue hues indicate warm dust heated by young stars. Herschel's instruments contributed the image data shown in red and green, revealing dust emission from cooler and intermediate regions where star formation is just beginning or has stopped. Dominated by dust emission, the Large Magellanic Cloud's infrared appearance is different from views in optical images. But this galaxy's well-known Tarantula Nebula still stands out, easily seen here as the brightest region to the left of center. A mere 160,000 light-years distant, the Large Cloud of Magellan is about 30,000 light-years across.

March 22, 2013

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The broad dust tail of Comet PanSTARRS (C/2011 L4) has become a familiar sight for many northern hemisphere comet watchers, as the comet fades but rises higher above the western horizon after sunset. This view of the popular comet may seem a little fantastic, though. Sweeping away from the Sun and trailing behind the comet's orbit, the curving dust tail also seems to stream away from a shining mountaintop castle. Comet Castle might be an appropriate name in this scene, but its traditional name is Castle Hohenzollern. Taken on March 15 with an extreme telephoto lens, the Comet Castle image was captured in exceptionally clear skies about 80 kilometers away from Stuttgart, Germany.

March 21, 2013

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Moving left to right near the center of this beautifully detailed color composite, the thin, bright, braided filaments are actually long ripples in a sheet of glowing gas seen almost edge on. The interstellar shock wave plows through space at over 500,000 kilometers per hour. Cataloged as NGC 2736, its elongated appearance suggests its popular name, the Pencil Nebula. The Pencil Nebula is about 5 light-years long and 800 light-years away, but represents only a small part of the Vela supernova remnant. The Vela remnant itself is around 100 light-years in diameter, the expanding debris cloud of a star that was seen to explode about 11,000 years ago. Initially, the shock wave was moving at millions of kilometers per hour but has slowed considerably, sweeping up surrounding interstellar material. In the narrowband, wide field image, red and blue-green colors track the characteristic glow of ionized hydrogen and oxygen atoms.

March 20, 2013

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The Great Nebula in Orion, an immense, nearby starbirth region, is probably the most famous of all astronomical nebulas. Here, glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud only 1500 light-years away. In the above deep image in assigned colors highlighted by emission in oxygen and hydrogen, wisps and sheets of dust and gas are particularly evident. The Great Nebula in Orion can be found with the unaided eye near the easily identifiable belt of three stars in the popular constellation Orion. In addition to housing a bright open cluster of stars known as the Trapezium, the Orion Nebula contains many stellar nurseries. These nurseries contain much hydrogen gas, hot young stars, proplyds, and stellar jets spewing material at high speeds. Also known as M42, the Orion Nebula spans about 40 light years and is located in the same spiral arm of our Galaxy as the Sun.

March 19, 2013

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How did the Moon form? To help find out, NASA launched the twin Gravity Recovery and Interior Laboratory (GRAIL) satellites in 2011 to orbit and map the Moon's surface gravity in unprecedented detail. Pictured above is a resulting GRAIL gravity map, with regions of slightly lighter gravity shown in blue and regions of slightly stronger gravity shown in red. Analysis of GRAIL data indicates that the moon has an unexpectedly shallow crust than runs about 40 kilometers deep, and an overall composition similar to the Earth. Although other surprising structures have been discovered that will continue to be investigated, the results generally bolster the hypothesis that the Moon formed mostly from Earth material following a tremendous collision in the early years of our Solar System, about 4.5 billion years ago. After completing their mission and running low on fuel, the two GRAIL satellites, Ebb and Flow, were crashed into a lunar crater at about 6,000 kilometer per hour.

March 18, 2013

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Have you seen the comet? As Comet PANSTARRS fades, careful observers - even with unaided eyes - should still be able to find the shedding ice ball on the western horizon just after sunset. Pictured above, Comet PANSTARRS (C/2011 L4) was pointed out from a hilltop last week on First Encounter Beach in Massachusetts, USA. The comet was discovered by - and is named for - the Pan-STARRS astronomical sky survey that discovered it. As the comet now recedes from both the Earth and the Sun, it will remain visible further into the night, although binoculars or a small telescope will soon to be needed to find it.

March 17, 2013

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What caused this outburst of V838 Mon? For reasons unknown, star V838 Mon's outer surface suddenly greatly expanded with the result that it became the brightest star in the entire Milky Way Galaxy in January 2002. Then, just as suddenly, it faded. A stellar flash like this had never been seen before - supernovas and novas expel matter out into space. Although the V838 Mon flash appears to expel material into space, what is seen in the above image from the Hubble Space Telescope is actually an outwardly moving light echo of the bright flash. In a light echo, light from the flash is reflected by successively more distant rings in the complex array of ambient interstellar dust that already surrounded the star. V838 Mon lies about 20,000 light years away toward the constellation of the unicorn (Monoceros), while the light echo above spans about six light years in diameter.

March 16, 2013

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Still looking for that comet? Comet PanSTARRS (C/2011 L4) naked-eye appearance in the northern hemisphere is described by successful comet spotters as a dim star with faint a tail. If you want to catch it the next few days could be your best bet. Start looking low and almost due west about 45 minutes after sunset. Of course, clear skies and a pair of binoculars should help a lot. Sky photographer Jean-Luc Dauvergne found suitable weather and western horizon for this comet and crescent Moon portrait after a road trip on March 13. Seeing PanSTARRS for the first time, he recorded the beautiful twilight scene with a telephoto lens near historical Alesia in France.

March 15, 2013

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After appearing in a popular photo opportunity with a young crescent Moon near sunset, naked-eye Comet PanSTARRS continues to rise in northern hemisphere skies. But this remarkable interplanetary perspective from March 13, finds the comet posing with our fair planet itself - as seen from the STEREO Behind spacecraft. Following in Earth's orbit, the spacecraft is nearly opposite the Sun and looks back toward the comet and Earth, with the Sun just off the left side of the frame. At the left an enormous coronal mass ejection (CME) is erupting from a solar active region. Of course, CME, comet, and planet Earth are all at different distances from the spacecraft. (The comet is closest.) The processed digital image is the difference between two consecutive frames from the spacecraft's SECCHI Heliospheric Imager, causing the strong shadowing effect for objects that move between frames. Objects that are too bright create the sharp vertical lines. The processing reveals complicated feather-like structures in Comet PanSTARRS's extensive dust tail.

March 14, 2013

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In silhouette against the colorful evening twilight glow, clouds part in this much anticipated magic moment. The scene captures naked-eye Comet PanSTARRS peeking into northern hemisphere skies on March 12. The comet stands over the western horizon after sunset, joined by the thin, flattened crescent of a day old Moon. Posing for its own beauty shot, the subtly lit dome of the 4.2 meter William Herschel Telescope is perched above cloud banks on the Canary Island of La Palma. While PanSTARRS has not quite developed into the spectacular comet once hoped for, it is still growing easier to see in the north. In coming days it will steadily climb north, farther from the Sun into darker western evening skies.

March 13, 2013

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Planetary nebulae can look simple, round, and planet-like in small telescopes. But images from the orbiting Hubble Space Telescope have become well known for showing these fluorescent gas shrouds of dying Sun-like stars to possess a staggering variety of detailed symmetries and shapes. This composite color Hubble image of NGC 6751, the Glowing Eye Nebula, is a beautiful example of a classic planetary nebula with complex features. It was selected in April of 2000 to commemorate the tenth anniversary of Hubble in orbit, but was reprocessed recently by an amateur as part of the Hubble Legacy program. Winds and radiation from the intensely hot central star (140,000 degrees Celsius) have apparently created the nebula's streamer-like features. The nebula's actual diameter is approximately 0.8 light-years or about 600 times the size of our Solar System. NGC 6751 is 6,500 light-years distant in the high-flying constellation of the Eagle (Aquila).

March 12, 2013

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How fast can a black hole spin? If any object made of regular matter spins too fast - it breaks apart. But a black hole might not be able to break apart - and its maximum spin rate is really unknown. Theorists usual model rapidly rotating black holes with the Kerr solution to Einstein's General Theory of Relativity, which predicts several amazing and unusual things. Perhaps its most easily testable prediction, though, is that matter entering a maximally rotating black hole should be last seen orbiting at near the speed of light, as seen from far away. This prediction was tested recently by NASA's NuSTAR and ESA's XMM satellites by observing the supermassive black hole at the center of spiral galaxy NGC 1365. The near light-speed limit was confirmed by measuring the heating and spectral line broadening of nuclear emissions at the inner edge of the surrounding accretion disk. Pictured above is an artist's illustration depicting an accretion disk of normal matter swirling around a black hole, with a jet emanating from the top. Since matter randomly falling into the black hole should not spin up a black hole this much, the NuSTAR and XMM measurements also validate the existence of the surrounding accretion disk.

March 11, 2013

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Why does a volcanic eruption sometimes create lightning? Pictured above, the Sakurajima volcano in southern Japan was caught erupting in early January. Magma bubbles so hot they glow shoot away as liquid rock bursts through the Earth's surface from below. The above image is particularly notable, however, for the lightning bolts caught near the volcano's summit. Why lightning occurs even in common thunderstorms remains a topic of research, and the cause of volcanic lightning is even less clear. Surely, lightning bolts help quench areas of opposite but separated electric charges. One hypothesis holds that catapulting magma bubbles or volcanic ash are themselves electrically charged, and by their motion create these separated areas. Other volcanic lightning episodes may be facilitated by charge-inducing collisions in volcanic dust. Lightning is usually occurring somewhere on Earth, typically over 40 times each second.

March 10, 2013

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Aloha and welcome to a breathtaking skyscape. The dreamlike panoramic view looks out from the 4,200 meter volcanic summit of Mauna Kea, Hawai'i, across a layer of clouds toward a starry night sky and the rising Milky Way. Anchoring the scene on the far left is the dome of the Canada-France-Hawaii Telescope (CFHT), with north star Polaris shining beyond the dome to the right. Farther right, headed by bright star Deneb, the Northern Cross asterism is embedded along the plane of the Milky Way as it peeks above the horizon. Both Northern Cross and brilliant white Vega hang over a foreground grouping of cinder cones. Near the center are the reddish nebulae, stars and dust clouds of the central Milky Way. Below, illumination from the city lights of Hilo creates an eerie, greenish glow in the clouds. Red supergiant star Antares shines above the Milky Way's central bulge while bright Alpha Centauri lies still farther right, along the dusty galactic plane. Finally, at the far right is the large Gemini North Observatory. The compact group of stars known as the Southern Cross is just left of the telescope dome.

March 9, 2013

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Sweeping quickly through southern skies on March 5, Comet PanSTARRS (C/2011 L4) follows the Sun toward the western horizon in this twilight scene. In the foreground is Australia's CSIRO Parkes Radio Telescope, a 64 meter wide steerable dish that is no stranger to the space age exploration of comets. In March of 1986 the Parkes dish tracked ESA's Giotto spacecraft as it flew by Comet Halley and received the first ever closeup images of Halley's nucleus. At naked-eye visibility, Comet PanSTARRS made its closest approach to planet Earth on March 5. Its closest approach to the Sun will be on March 10. Heading north, PanSTARRS now begins a much anticipated appearance low in the northern hemisphere's western skies after sunset. On March 12, look for the comet hugging the western horizon near a young crescent Moon.

March 8, 2013

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Want to use a cluster of galaxies as a telescope? It's easier than you might think as distant galaxy clusters naturally act as strong gravitional lenses. In accordance with Einstein's theory of general relativity, the cluster gravitational mass, dominated by dark matter, bends light and creates magnified, distorted images of even more distant background galaxies. This sharp infrared Hubble image illustrates the case for galaxy cluster Abell 68 as a gravitational telescope, explored by amateur astronomer Nick Rose during the ESA-Hubble Hidden Treasures image processing competition. Labels 1 and 2 show two lensed images of the same background galaxy. The distorted galaxy image labeled 2 resembles a vintage space invader! Label 3 marks a cluster member galaxy, not gravitationally lensed, stripped of its own gas as it plows through the denser intergalactic medium. Label 4 includes many background galaxies imaged as elongated streaks and arcs. Abell 68 itself is some 2.1 billion light-years distant toward the constellation Vulpecula. The central region of the cluster covered in the Hubble view spans over 1.2 million light-years.

March 7, 2013

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Fomalhaut (sounds like "foam-a-lot") is a bright, young, star, a short 25 light-years from planet Earth in the direction of the constellation Piscis Austrinus. In this sharp composite from the Hubble Space Telescope, Fomalhaut's surrounding ring of dusty debris is imaged in detail, with overwhelming glare from the star masked by an occulting disk in the camera's coronagraph. Astronomers now identify, the tiny point of light in the small box at the right as a planet about 3 times the mass of Jupiter orbiting 10.7 billion miles from the star (almost 23 times the Sun-Jupiter distance). Designated Fomalhaut b, the massive planet probably shapes and maintains the ring's relatively sharp inner edge, while the ring itself is likely a larger, younger analog of our own Kuiper Belt - the solar system's outer reservoir of icy bodies. The Hubble data represent the first visible-light image of a planet circling another star.

March 6, 2013

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Bright clusters and nebulae abound in the ancient northern constellation of Auriga. The region includes the open star cluster M38, emission nebula IC 410 with Tadpoles, Auriga's own Flaming Star Nebula IC 405, and this interesting pair IC 417 (lower left) and NGC 1931. An imaginative eye toward the expansive IC 417 and diminutive NGC 1931 suggests a cosmic spider and fly. About 10,000 light-years distant, both represent young, open star clusters formed in interstellar clouds and still embedded in glowing hydrogen gas. For scale, the more compact NGC 1931 is about 10 light-years across.

March 5, 2013

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Two impressive comets will both reach their peak brightness during the next two weeks. Taking advantage of a rare imaging opportunity, both of these comets were captured in the sky together last week over the Atacama desert in South America. Comet C/2012 F6 (Lemmon), visible on the upper left of the above image, is sporting a long tail dominated by glowing green ions. Comet C/2011 L4 (PanSTARRS), visible near the horizon on the lower right, is showing a bright tail dominated by dust reflecting sunlight. The tails of both comets point approximately toward the recently set Sun. Comet Lemmon will be just barely visible to the unaided eye before sunset in southern skies for the next week, and then best viewed with binoculars as it fades and moves slowly north. Comet PanSTARRS, however, will remain visible in southern skies for only a few more days, after which it will remain bright enough to be locatable with the unaided eye as it moves into northern skies. To find the giant melting snowball PanSTARRS, sky enthusiasts should look toward the western horizon just after sunset. Deep sky observers are also monitoring the brightening of Comet C/2012 S1 (ISON), which may become one of the brightest objects in the entire night sky toward the end of 2013.

March 4, 2013

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Sprawling across almost 200 light-years, emission nebula IC 1805 is a mix of glowing interstellar gas and dark dust clouds. Derived from its Valentine's-Day-approved shape, its nickname is the Heart Nebula. About 7,500 light-years away in the Perseus spiral arm of our galaxy, stars were born in IC 1805. In fact, near the cosmic heart's center are the massive hot stars of a newborn star cluster also known as Melotte 15, about 1.5 million years young. A little ironically, the Heart Nebula is located in the constellation of the mythical Queen of Aethiopia (Cassiopeia). This deep view of the region around the Heart Nebula spans about two degrees on the sky or about four times the diameter of the Full Moon.

March 3, 2013

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One of the natural wonders of planet Earth, the Grand Canyon in the American southwest stretches across this early evening skyscape. The digitally stacked sequence reveals the canyon's layers of sedimentary rock in bright moonlight. Exposed sedimentary rock layers range in age from about 200 million to 2 billion years old, a window to history on a geological timescale. A recent study has found evidence that the canyon itself may have been carved by erosion as much as 70 million years ago. With the camera fixed to a tripod while Earth rotates, each star above carves a graceful arc through the night sky. The concentric arcs are centered on the north celestial pole, the extension of Earth's rotation axis into space, presently near the bright star Polaris.

March 2, 2013

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Each day on planet Earth can have a serene beginning at sunrise as the sky gently grows bright over a golden eastern horizon. This sunrise panorama seems to show such a moment on the winter morning of February 15. In the mist, a calm, mirror-like stretch of the Miass River flows through the foreground along a frosty landscape near Chelyabinsk, Russia. But the long cloud wafting through the blue sky above is the evolving persistent train of the Chelyabinsk Meteor. The vapor trail was left by the space rock that exploded over the city only 18 minutes earlier, causing extensive damage and injuring over 1,000 people. A well-documented event, the numerous webcam and dashcam video captures from the region soon contributed to a reconstruction of the meteor's trajectory and an initial orbit determination. Preliminary findings indicate the parent meteoriod belonged to the Apollo class of Earth crossing asteroids.

March 1, 2013

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The colors of the solar system's innermost planet are enhanced in this tantalizing view, based on global image data from the Mercury-orbiting MESSENGER spacecraft. Human eyes would not discern the clear color differences but they are real none the less, indicating distinct chemical, mineralogical, and physical regions across the cratered surface. Notable at the upper right, Mercury's large, circular, tan colored feature known as the Caloris basin was created by an impacting comet or asteroid during the solar system's early years. The ancient basin was subsequently flooded with lava from volcanic activity, analogous to the formation of the lunar maria. Color contrasts also make the light blue and white young crater rays, material blasted out by recent impacts, easy to follow as they extend across a darker blue, low reflectance terrain.

[Myattboy]

Originally Posted by Spenner

As far as cameras go, the Canon 20Da, while I'm not sure WHERE to get it, is designed specifically for astrophotography, being that it doesn't filter out infrared light and will produce higher contrast and sharper photos.

http://en.wikipedia.org/wiki/Eos_20d#EOS_20Da

However apparently now there's a Canon 60Da which clearly would be more desirable for basically the same cost

http://en.wikipedia.org/wiki/Canon_EOS_60Da#EOS_60Da

Though these are quite pricey. What is your budget for the photographic end of this? With that telescope all you'll be needing is a body for the camera and either using it with a remote shutter, or simply plugging the camera into a laptop and doing it live.

EDIT: Woops, didn't read that you've already been doing astrophotography. Either way, some more info if your camera isn't up to par :P

I've haven't attempted any kind of astrophotography yet, just live viewing so I'll have a good look at the camera you suggested when i get the time. Thank you.
Also, when i said "Do you think it'll be good for taking long exposures as well?" in my previous post, i was referring to the stability of the mount as i've read that a decent mount is required for astrophotography.
I'm new to both astronomy and photography so bear with me if i sound clueless lol.

[Bluearrowll]

Originally Posted by Myattboy

I've haven't attempted any kind of astrophotography yet, just live viewing so I'll have a good look at the camera you suggested when i get the time. Thank you.
Also, when i said "Do you think it'll be good for taking long exposures as well?" in my previous post, i was referring to the stability of the mount as i've read that a decent mount is required for astrophotography.
I'm new to both astronomy and photography so bear with me if i sound clueless lol.

Something to keep in mind is that the longer the exposure you take, the higher the need for a mount that will rotate with the Earth. When I take a photo, star trails are annoyingly long in as little an exposure as 15 seconds. Finding a telescope that has such a mount or a tripod that has such a mount would do wonders to you.

http://www.telescope.com/Mounts-Trip...e=SortByRating

http://www.telescope.com/Mounts-Trip...ByRating#tab-6

Here are a couple tripods that would help you shoot long exposure pictures. One of them is considerably more expensive than the other, but remember these are dollar values, so for your currency they might be a bit cheaper. Both of them appear to have very positive reviews, which is typically a good sign of a good product. Also for the more inexpensive one, take a look at some of the photos that people have taken with it as a mount!


What's in the sky tonight?
April 7, 2012

-The bright Moon rises around the end of twilight below Saturn and Spica in the east-southeast. Later in the evening the three shine higher: a long, narrow triangle with the Moon at the bottom.

-Saturn (magnitude +0.2, in Virgo) is at opposition April 15th. This week it rises almost around sunset and stands highest in the south around 1 or 2 a.m. daylight-saving time. Shining 5½° to Saturn's right is Spica: fainter, bluer, and twinklier.

-Keep careful watch on Saturn and its rings in a telescope. In the days leading up to opposition, watch for the Seeliger effect: a brightening of the rings with respect to the globe. This happens because the solid particles making up the rings backscatter sunlight (reflect it back in the direction it came from) more effectively than the planet's cloudtops do.

Astro Picture of the Day:
April 7, 2012

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The star near the top is so bright that it is sometimes hard to notice the galaxy toward the bottom. Pictured above, both the star, Regulus, and the galaxy, Leo I, can be found within one degree of each other toward the constellation of the Lion (Leo). Regulus is part of a multiple star system, with a close companion double star visible to the lower left of the young main sequence star. Leo I is a dwarf spheroidal galaxy in the Local Group of galaxies dominated by our Milky Way Galaxy and M31. Leo I is thought to be the most distant of the several known small satellite galaxies orbiting our Milky Way Galaxy. Regulus is located about 75 light years away, in contrast to Leo 1 which is located about 800,000 light years away. Regulus is easy to spot these days as it is accompanied by Mars after sunset and hangs around until the early morning hours.

[Bluearrowll]

What's in the sky tonight?
April 8, 2012

-As twilight fades down, Look for bright Sirius in the southwest, Orion's horizontal Belt off to the right, and Aldebaran and Venus farther to the right in the west. They all form a long, almost straight line. The line is horizontal if you live near latitude 38° north.

-Venus (magnitude –4.6; in Taurus) shines very high and ever more brilliant in the west during and after twilight. It doesn't set now until some 2½ hours after dark. This is just about as high and bright as Venus ever becomes in its 8-year cycle of apparitions. Look to its lower right for the Pleiades, and to its left for orange Aldebaran.

Astro Picture of the Day:
April 8, 2012

Source:
Hurtling through a cosmic dust cloud some 400 light-years away, the lovely Pleiades or Seven Sisters star cluster is well-known for its striking blue reflection nebulae. In the dusty sky toward the constellation Taurus and the Orion Arm of our Milky Way Galaxy, this remarkable image shows the famous star cluster at the upper left. But lesser known dusty nebulae lie along the region's fertile molecular cloud, within the 10 degree wide field, including the bird-like visage of LBN 777 near center. Small bluish reflection nebula VdB 27 at the lower right is associated with the young, variable star RY Tau. At the distance of the Pleiades, the 5 panel mosaic spans nearly 70 light-years. The dust clouds are seen as brown clouds, not to be confused with clouds that might be seen in terrestrial levels.

[Bluearrowll]

What's in the sky tonight?
April 9, 2012

-The Big Dipper, high in the northeast, dumps water into the dim Little Dipper during evening at this time of year.

-Jupiter is sinking ever lower toward the sunset far below Venus. Jupiter is rounding toward the far side of the Sun, which is why a telescope shows it a disappointingly small 33 arcseconds wide. In addition, Jupiter appears increasingly fuzzy at its ever-lower altitude.

Astro Picture of the Day:
April 9, 2012

Source:
Strange shapes and textures can be found in neighborhood of the Cone Nebula. The unusual shapes originate from fine interstellar dust reacting in complex ways with the energetic light and hot gas being expelled by the young stars. The brightest star on the right of the above picture is S Mon, while the region just below it has been nicknamed the Fox Fur Nebula for its color and structure. The blue glow directly surrounding S Mon results from reflection, where neighboring dust reflects light from the bright star. The red glow that encompasses the whole region results not only from dust reflection but also emission from hydrogen gas ionized by starlight. S Mon is part of a young open cluster of stars named NGC 2264, located about 2500 light years away toward the constellation of the Unicorn (Monoceros). The origin of the mysterious geometric Cone Nebula, visible on the far left, remains a mystery.

[Bluearrowll]

This thread has now lasted one month! What has happened in that month?

-1,200 views.
-67 posts.
-31 Pictures and a month of learning what's in the sky that most of us can see.
-Contributions from members about finding helpful links to astronomical related sites, cameras, telescopes.
-A stickied thread.
-1,200 views / 31 days means on average, 38.7 people view this thread a day. Thank you for helping this thread maintain its splendour.
-Several new features, including a Light pollution map, Messier Map, new links.

My question now comes to you, the viewer: What would you like to see added to this thread? Perhaps someone could make a neat banner to head the thread. I'm in the final exam period so I don't quite have the time to do it, but a major thank you to all who regularly view this thread!

Now having said that...

What's in the sky tonight?
April 10, 2012

-The bright star high to the upper right of Venus these evenings is Capella, the Goat Star. It's the same yellow-white color, and thus the same temperature, as the Sun. The wavelength of the star is a good measurement of indicating how hot a star is. It's also how we know the temperature of our own sun! The shorter the wavelength, the warmer the star. Wavelengths are also used to calculate how fast the star is moving to, or from us by how much it has redshifted (how much the elemental spectra of a star has moved to the longer end of the spectrum compared to the elemental spectra at rest state found here, and as such, is moving away) or blueshifted (how much the elemental spectra of a star has moved to the shorter end of the spectrum compared to the elemental spectra at rest state found here, and as such, is heading towards us). The greater the shift, the faster the object is moving to or from us.

-You can see Venus in the clear blue sky of daytime, if your eye lands right on it. The best time to examine Venus in a telescope is late afternoon or around sunset. It's now a thick crescent that has grown to 27 arcseconds tall as it rounds the Sun and approaches Earth.

Astro Picture of the Day:
April 10, 2012

Source:
Does part of this image look familiar? In the second picture in as many days, the Cone Nebula is revisited with its many friends in a more zoomed out scale. Found in Monoceros, pictured above is a star forming region cataloged as NGC 2264, the complex jumble of cosmic gas and dust is about 2,700 light-years distant and mixes reddish emission nebulae excited by energetic light from newborn stars with dark interstellar dust clouds. Where the otherwise obscuring dust clouds lie close to the hot, young stars they also reflect starlight, forming blue reflection nebulae. The above image spans about 3/4 degree or nearly 1.5 full moons, covering 40 light-years at the distance of NGC 2264. Its cast of cosmic characters includes the Fox Fur Nebula, whose convoluted pelt lies at the upper left, bright variable star S Mon immersed in the blue-tinted haze just below the Fox Fur, and the Cone Nebula near the tree's top. Of course, the stars of NGC 2264 are also known as the Christmas Tree star cluster. The triangular tree shape traced by the stars appears sideways here, with its apex at the Cone Nebula and its broader base centered near S Mon.

[Spenner]

Originally Posted by Bluearrowll

Something to keep in mind is that the longer the exposure you take, the higher the need for a mount that will rotate with the Earth. When I take a photo, star trails are annoyingly long in as little an exposure as 15 seconds. Finding a telescope that has such a mount or a tripod that has such a mount would do wonders to you.

This will be a very important factor for astrophotography- if you get even the slightest out of sync rotation, the pixels of the image will be very soft and you won't get a good image out of it. Also something to look for in a camera is the high ISO/noise performance. The better the camera can handle low-light conditions, the less artifacts and noisy pixels you'll see. Generally Nikons are known for low-light performance, but a lot of Canons hold up just as well (though some have pretty bad low-light performance, like my Canon Rebel T1i )

[Bluearrowll]

What's in the sky tonight?
April 11, 2012

-With the Moon gone from the evening sky, it's deep-sky observing time again. Telescope users are familiar with the "Leo Trio" of galaxies (M65, M66, and NGC 3628) by the little chair asterism in the back leg of Leo. Can you detect M65 and M66 with binoculars?

-Toronto residents should consider the International Space Station Tracker as the Space Station makes very visible passes over the city tonight and an even brighter appearance tomorrow night at a reasonable hour. There will be two passes tonight:

Pass A:
This pass rises above the horizon at 20:20:54, and enters the shadow of the Earth at 20:30:09. The maximum altitude time is 20:25:52, and it will appear 26 degrees high at its peak. At it's peak it will appear in the Southeast.

Event Time Altitude Azimuth Distance (km)
Rises above horizon 20:20:54 -0° 209° (SSW) 2,283
Reaches 10° altitude 20:23:09 10° 196° (SSW) 1,435
Maximum altitude 20:25:52 26° 138° (SE ) 818
Enters shadow 20:30:09 3° 69° (ENE) 1,998
Drops below 10° altitude20:28:40 10° 78° (ENE) 1,446


Use the following star map to get a feel for the location and how fast the space station travels throughout it's ~6 minute appearance. More details can be found in the link in "Pass A".


Pass B:
This is the better of the two passes tonight. At its peak, the space station will be almost 300 km closer to us, and the sun will also have long set. The maximum altitude will be 45 degrees - halfway up the sky.

Event Time Altitude Azimuth Distance (km)
Rises above horizon 21:56:46 0° 253° (WSW) 2,292
Reaches 10° altitude 21:58:52 10° 260° (W ) 1,442
Maximum altitude 22:02:00 45° 335° (NNW) 553
Enters shadow 22:02:37 39° 10° (N ) 615

Use the following star map to get a feel for the location and how fast the space station travels throughout it's ~6 minute appearance. More details can be found in the link in "Pass B".



NOTE: These times are specifically calculated for TORONTO, ON. If you're interested and wish to have a shot at looking at the Space Station, open the "International Space Station Tracker" tab in this thread, and follow the instructions. Good luck, and don't blink!

Astro Picture of the Day:
April 11, 2012

Source:
Why would Venus appear oval? Venus has been seen countless times from the surface of the Earth, and every time the Earth's atmosphere has dispersed its light to some degree. When the air has just the right amount of dust or water droplets, small but distant objects like Venus appear spread out into an angularly large aureole. Aureoles are not unusual to see and are frequently noted as circular coronas around the Sun or Moon. Recently, however, aureoles have been imaged that are not circular but distinctly oval. The above oval Venusian aureole was imaged by the astrophotographer who first noted the unusual phenomenon three years ago. Initially disputed, the unusual distortion has now been confirmed multiple times by several different astrophotographers. What causes the ellipticity is currently unknown, and although several hypotheses hold that horizontally oriented ice crystals are responsible, significant discussions about it are still taking place.

[Spenner]

Originally Posted by Spenner

stuff

As well, I forgot about some key points that this goes over:

http://www.luminous-landscape.com/tu...60-night.shtml

Especially read "rule of 600" because that will be handy when choosing the exposure time.

I'm feeling adventurous, if skies are well tonight I might try some sky shots of my own.

[Bluearrowll]

What's in the sky tonight?
April 12, 2012

-Near the back leg of Leo is the asteroid 5 Astraea, about magnitude 9.6. Use this preview to track the location of the asteroid. It can be found on page 52.

-Toronto residents get the best view of the space station tonight of the month incase you missed the 2 passes last night. The next good pass is well over a week away, so take advantage of the weather. You will be looking for a bright white-yellow ball moving at a high speed (think about the speed of a plane, but only identifyable as a dot) beginning by cutting through Orion, past Gemini, and passing the Big Dipper, before passing Bootes and siappearing into the Corona Borealis constellation. Don't miss out on this one!

Pass A:
This pass rises above the horizon at 21:00:38, and enters the shadow of the Earth at 21:09:33. The maximum altitude time is 21:05:54, and it will appear 80 degrees high at its peak in the northwest - just 10 degrees shorter than the maximum.

Event Time Altitude Azimuth Distance (km)
Rises above horizon 21:00:38 -0° 239° (WSW) 2,288
Reaches 10° altitude 21:02:41 10° 241° (WSW) 1,439
Maximum altitude 21:05:54 80° 320° (NW ) 407
Enters shadow 21:09:33 8° 57° (ENE) 1,606
Drops below 10° altitude 21:09:10 10° 56° (ENE) 1,449


Use the following star map to get a feel for the location and how fast the space station travels throughout it's ~6 minute appearance. More details can be found in the link in "Pass A".

NOTE: These times are specifically calculated for TORONTO, ON. If you're interested and wish to have a shot at looking at the Space Station, open the "International Space Station Tracker" tab in this thread, and follow the instructions. Good luck, and don't blink!

Astro Picture of the Day:
April 12, 2012

Source:
On another April 12th, in 1961, Soviet cosmonaut Yuri Alexseyevich Gagarin became the first human to see planet Earth from space. Commenting on his view from orbit he reported, "The sky is very dark; the Earth is bluish. Everything is seen very clearly". To celebrate, consider this recent image from the orbiting International Space Station. A stunning view of the planet at night from an altitude of 240 miles, it was recorded on March 28. The lights of Moscow, Russia are near picture center and one of the station's solar panel arrays is on the left. Aurora and the glare of sunlight lie along the planet's gently curving horizon. Stars above the horizon include the compact Pleiades star cluster, immersed in the auroral glow. The effect of light pollution is shown in this photo as brown-yellow light domes are clearly visible.

[Bluearrowll]

What's in the sky tonight?
April 13, 2012

-Summer preview: stay up until 11 and look northeast, and you'll get a preview of bright Vega, the "Summer Star" in little Lyra, climbing into good view. This is an astronomical sign that summer is approaching for North Americans.

-Last-quarter Moon (exact at 6:50 a.m. on this date EDT).

Astro Picture of the Day:
April 13, 2012

Source:
Reflection nebulas reflect light from a nearby star. Many small carbon grains in the nebula reflect the light. The blue color typical of reflection nebula is caused by blue light being more efficiently scattered by the carbon dust than red light. The brightness of the nebula is determined by the size and density of the reflecting grains, and by the color and brightness of the neighboring star(s). NGC 1435, pictured above, surrounds Merope (23 Tau), one of the brightest stars in the Pleiades (M45). The Pleiades nebulosity is caused by a chance encounter between an open cluster of stars and a dusty molecular cloud.

[Bluearrowll]

What's in the sky tonight?
April 14, 2012

-Saturn is at opposition, opposite the Sun. It rises around sunset, shines highest in the middle of the night, and sets around sunrise. Telescope users: watch for the Seeliger effect, described under Saturn in "This Week's Planet Roundup" below.

-Mars ends its retrograde (westward) motion for the year and resumes heading east against the background stars. Watch it pull away from Regulus in the coming weeks: slowly at first, then faster.

Astro Picture of the Day:
April 14, 2012

Source:
How many moons does Saturn have? So far 62 have been discovered, the smallest only a fraction of a kilometer across. Six of its largest satellites can be seen here, though, in a sharp Saturnian family portrait taken on March 9. Larger than Earth's Moon and even slightly larger than Mercury, Titan has a diameter of 5,150 kilometers and starts the line-up at the lower left. Continuing to the right across the frame are Mimas, Tethys, [Saturn], Enceladus, Dione, and Rhea at far right. Saturn's first known natural satellite, Titan was discovered in 1655 by Dutch astronomer Christiaan Huygens, while most recently the satellite provisionally designated S/2009 S1 was found by the Cassini Imaging Science Team in 2009. Tonight, Saturn reaches opposition in planet Earth's sky, offering the best telescopic views of the ringed planet and moons.

[Bluearrowll]

What's in the sky tonight?
April 15, 2012

-Venus (magnitude –4.6; in Taurus) is shining the highest and brightest it ever appears in the evening sky during its 8-year cycle of repeating apparitions. Venus comes into easy view high in the west soon after sunset. It doesn't set in the northwest until around 11 or even midnight daylight saving time (depending on where you live). You can see Venus through the clear blue sky of day if your eye lands right on it; look for it 44° (4 or 5 fist-widths at arm's length) to the Sun's celestial east-northeast.

Look high to Venus's upper right at dusk for Capella, to its lower left for Aldebaran, and to its lower right for the Pleiades. Far below Venus in twilight is Jupiter.

The best time to examine Venus in a telescope is late afternoon or around sunset. It's now a thick crescent 30 arcseconds tall and 40% sunlit, waning and enlarging week by week as it swings toward Earth.

-Keep careful watch on Saturn and its rings in a telescope. With Saturn at or near near opposition, notice the Seeliger effect: a temporary brightening of the rings with respect to the globe. This happens because the solid particles making up the rings backscatter sunlight (reflect it back in the direction it came from) more effectively than the planet's cloudtops do. Compare how the rings and globe look now with with how they look a week or more past opposition.

Astro Picture of the Day:
April 15, 2012

Source:
This telescopic close-up shows off the otherwise faint emission nebula IC 410 in striking false-colors. It also features two remarkable inhabitants of the cosmic pond of gas and dust above and left of center, the tadpoles of IC 410. The picture is a composite of images taken through both broad and narrow band filters. The narrow band data traces atoms in the nebula, with emission from sulfur atoms in red, hydrogen atoms in green, and oxygen in blue. Partly obscured by foreground dust, the nebula itself surrounds NGC 1893, a young galactic cluster of stars that energizes the glowing gas. Composed of denser cooler gas and dust the tadpoles are around 10 light-years long, potentially sites of ongoing star formation. Sculpted by wind and radiation from the cluster stars, their tails trail away from the cluster's central region. IC 410 lies some 12,000 light-years away, toward the constellation Auriga.

[Reach]

Fantastic thread, even for casuals just looking at the pictures.

I absolutely love the picture from April 12. I don't see this video posted anywhere in this thread, so:

http://www.youtube.com/watch?v=FG0fTKAqZ5g

An incredible time-lapse from the ISS for those interested.

[gold stinger]

This thread is the most up-to-date thread I've ever seen. D:

[Winrar]

Even though I don't understand a lot of it. The pictures are amazing and open my eyes to what we're all missing out on. There's just so much we don't know.

[Bluearrowll]

Thanks Reach, gold stinger, Winrar for the positive feedback! Reach, I have added the ISS video under the ISS tab because that's a great video and really gives perspective on what it's like to see the Earth from above.

If there's something you want to see added to the thread, post a suggestion! It might just start appearing in the main post.

What's in the sky tonight?
April 16, 2012

-As twilight fades, Look for bright Sirius in the southwest, Orion's horizontal Belt off to the right (with Betelgeuse above it, Rigel below it), and Aldebaran and Venus farther to the right in the west. As it sinks ever lower in the west, notice how it starts twinkling more violently, even temporarily changing colours to yellows and reds. Why is this? As it lowers into the horizon, Sirius and other stars have more atmosphere to travel to from your eyes to the location of the star. Because of this, the light of the star is often distorted through the increased atmosphere and can be strong enough to change what colour rays reach your eyes. This is the same reason why the Sun rises reddish in colour, and why the moon also rises in a red-orange colour. It also explains their often distorted and enlarged shape. Take this picture of the sun for example.

-Mercury (magnitude +0.4) is deep in the glow of sunrise. It's having a very poor dawn apparition just above the eastern horizon.

-Neptune (magnitude 7.9, in Aquarius) is barely emerging into view low in the east-southeast before dawn's first light. Both of these planets were hidden in the glare of the sun last week.

Astro Picture of the Day:
April 16, 2012

Source:
From afar, the whole thing looks like an Eagle. A closer look at the Eagle Nebula, however, shows the bright region is actually a window into the center of a larger dark shell of dust. Through this window, a brightly-lit workshop appears where a whole open cluster of stars is being formed. In this cavity tall pillars and round globules of dark dust and cold molecular gas remain where stars are still forming. Already visible are several young bright blue stars whose light and winds are burning away and pushing back the remaining filaments and walls of gas and dust. The Eagle emission nebula, tagged M16, lies about 6500 light years away, spans about 20 light-years, and is visible with binoculars toward the constellation of the Serpent (Serpens). This picture combines three specific emitted colors and was taken with the 0.9 meter telescope on Kitt Peak, Arizona, USA. The famous pillars are seen at the centre of this nebula.

[Bluearrowll]

What's in the sky tonight?
April 17, 2012

-The eclipsing variable star Algol is at minimum brightness, magnitude 3.4 instead of its usual 2.1, for a couple hours centered on 10:44 p.m. EDT (9:44 p.m. CDT). This is the last chance till August to see Algol at minimum from the latitudes of the U.S.
-Mercury (magnitude +0.4) is deep in the glow of sunrise. It's having a very poor dawn apparition just above the eastern horizon.

-Keep careful watch on Saturn and its rings in a telescope. With Saturn at or near near opposition, notice the Seeliger effect: a temporary brightening of the rings with respect to the globe. This happens because the solid particles making up the rings backscatter sunlight (reflect it back in the direction it came from) more effectively than the planet's cloudtops do. Compare how the rings and globe look now with with how they look a week or more past opposition. By April 12th, three days before Saturn's opposition, the planet's rings had already brightened quite noticeably due to the Seeliger effect. South is up. A comparison image by the same photographer has been posted below.

Astro Picture of the Day:
April 17, 2012

Source:
Antares is a huge star. In a class called red supergiant, Antares is about 850 times the diameter of our own Sun, 15 times more massive, and 10,000 times brighter. Antares is the brightest star in the constellation of Scorpius and one of the brighter stars in all the night sky. Located about 550 light years away, Antares is seen on the left surrounded by a yellowish nebula of gas which it has itself expelled. Radiation from Antares' blue stellar companion helps cause the nebular gas to glow. Far behind Antares, to the lower right in the above image, is the globular star cloud M4, while the bright star on the far right is Al Niyat.