Terry's Astronomy Thread.

[Bluearrowll]

What's in the sky tonight?
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.

News Posted Today:
April 29, 2013
One Gap, No Planets


Astro Picture of the Day:
May 1, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

News Posted Today:
May 1, 2013
Saturn is Making Waves


Astro Picture of the Day:
May 2, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

Astro Picture of the Day:
May 3, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

News Posted Today
May 3, 2013
Lingering Echoes of Comet S-L 9's Demise


Astro Picture of the Day:
May 4, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

Astro Picture of the Day:
May 5, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

Astro Picture of the Day:
May 6, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

Astro Picture of the Day:
May 7, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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].

Astro Picture of the Day:
May 8, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

Astro Picture of the Day:
May 9, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

Astro Picture of the Day:
May 10, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

News Posted Today:
May 10, 2013
A Cosmic Sleight of Hand


Astro Picture of the Day:
May 11, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

Astro Picture of the Day:
May 12, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

Astro Picture of the Day:
May 13, 2013

Source
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.

[Bluearrowll]

Here is a stream from NASA to see Chris Hadfield, Roman Romanenko and Tom Marshburn close the hatch and board the Soyuz on their voyage home.

http://www.ustream.tv/channel/6540154

EDIT: 7:08pm EST is when the official undocking will occur on this stream.

Schedule for tonight:

[Bluearrowll]

What's in the sky tonight?
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.

Astro Picture of the Day:
May 14, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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.

Astro Picture of the Day:
May 15, 2013

Source
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.

[Bluearrowll]

What's in the sky tonight?
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

Astro Picture of the Day:
May 16, 2013

Source
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.

[Bluearrowll]

Today I head off to Algonquin Park on a 2nd astrophotography trip - the last one being the previous year's Victoria Day weekend. Control of the thread will temporarily be passed on to Sky Kitten until I return Monday Night.

What's in the sky tonight?
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).

News Posted Today:
May 15, 2013
Kepler Goes Down - and Probably Out


Astro Picture of the Day:
May 17, 2013

Source
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

[Sky Kitten]

Hi guys. I totally forgot to do this for Terry due to stuff getting in the way (sorry about that!) so I will post the ones for the 18th and 19th right now, and do the 20th tomorrow.

What's in the sky tonight?
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.

Astro Picture of the Day:
May 18, 2013

Source
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.

[Sky Kitten]

What's in the sky tonight?
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).

Astro Picture of the Day:
May 19, 2013

Source
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.