Terry's Astronomy Thread.

[Bluearrowll]

Daily Suspicious0bserver's Weather Post:
August 14, 2014

What's in the sky tonight?
August 14, 2014

-Vega is almost overhead after dark. The brightest star in the southeast is Altair, nearly as bright. Altair is flagged by little Tarazed (3rd magnitude) a finger-width above it: an orange giant far in Altair's background.

-Observers reporting to the International Meteor Organization say that Perseid meteor rates are still high, greater than 40 per hour on Aug. 13-14. This means Earth has not yet exited the debris stream of parent comet Swift-Tuttle. If it is dark where you live, go outside and look up.

-Before the Perseid meteor shower began, forecasters worried that people might not see it due to the glare of a supermoon. This photo illustrates why the Perseids succeeded in spite of lunar interference; the shower is rich in fireballs. "This was the brightest Perseid I saw on the night of August 12/13," says photographer Pete Lawrence. "Visually, it was a stunner!"

After the meteor exploded over Lawrence's home in Selsey, UK, a wispy trail of debris appeared where the meteor had been a split-second before. "I recorded it in the very next frame," he says.

This is "meteor smoke," a sinuous cloud of microscopic cinders tracing the path of the incinerating fireball. The particles of meteor smoke disperse in Earth's upper atmosphere and, ultimately, become the seeds of noctilucent clouds. All meteors produce such smoke, but only the brightest fireballs create a lingering trail bright enough to see with the unaided eye.

Light from the supermoon, ironically, helps us see meteor smoke, because reflected moonlight increases the visibility of smoky debris. As a result, the smoke may have been photographed more often than usual during the 2014 Perseids.

-Every night, a network of NASA all-sky cameras scans the skies above the United States for meteoritic fireballs. Automated software maintained by NASA's Meteoroid Environment Office calculates their orbits, velocity, penetration depth in Earth's atmosphere and many other characteristics.

On Aug. 13, 2014, the network reported 163 fireballs. (99 Perseids, 61 sporadics, 1 Northern Delta Aquarid, 1 Southern Delta Aquarid, 1 Southern Iota Aquarid)

Astro Picture of the Day:
August 14, 2014

Source:
Big, bright, and beautiful, a Full Moon near perigee, the closest point in its elliptical orbit around our fair planet, rose on August 10. This remarkable picture records the scene with a dreamlike quality from the east coast of the United States. The picture is actually a composite of 10 digital frames made with exposures from 1/500th second to 1 second long, preserving contrast and detail over a much wider than normal range of brightness. At a perigee distance of a mere 356,896 kilometers, August's Full Moon was the closest, and so the largest and most super, of the three Full Moons nearest perigee in 2014 now popularly known as supermoons. But if you missed August's super supermoon, the next not-quite-so supermoon will be September 8. Then, near the full lunar phase the Moon's perigee will be a slightly more distant 358,387 kilometers. That's only about 0.4 percent less super (farther and smaller) than the super supermoon.