Astronomy Picture Of The Day - Page 6

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Just before the Sun blacks out, something strange occurs. As the Moon moves to completely cover the Sun in a total solar eclipse -- like the one set to occur over parts of Australia on Tuesday -- beads of bright sunlight stream around the edge of the Moon. This effect, known as Baily's beads, is named after Francis Baily who called attention to the phenomenon in 1836. Although, the number and brightness of Baily's beads used to be unpredictable, today the Moon is so well mapped that general features regarding Baily's beads are expected. When a single bead dominates, it is called the diamond ring effect, and is typically seen just before totality. Pictured above, horizontally compressed, a series of images recorded Baily's beads at times surrounding the 2008 total solar eclipse visible from Novosibirsk, Russia. At the end of totality, as the Sun again emerges from behind the moon, Baily's beads may again be visible -- but now on the other side of the Moon.

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Which feature takes your breath away first in this encompassing panorama of land and sky? The competition is strong with a waterfall, meteor, starfield, and even a moonbow all vying for attention. It is interesting to first note, though, what can't be seen -- a rising moon on the other side of the camera. The bright moon not only illuminated this beautiful landscape in Queensland, Australia last June, but also created the beautiful moonbow seen in front of Wallaman Falls. Just above the ridge in the above image is the horizontal streak of an airplane. Toward the top of the frame is the downward streak of a bright meteor, a small pebble from across our Solar System that lit up as it entered the Earth's atmosphere. Well behind the meteor are numerous bright stars and nebula seen toward the center of our Galaxy. Finally, far in the background, is the band of our Milky Way Galaxy, running diagonally from the lower left to the upper right in the image but also circling the entire sky.

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Some people are so inspired by solar eclipses that they quilt. Pictured above is a resulting textile from one such inspiration. The 38x38 inch quilt offers impressions of a total annular eclipse, when the Moon is too far from the Earth to cover the entire Sun, witnessed in Spain in October of 2005. Today, however, a full total solar eclipse will occur, although it will only be visible to eclipse chasers and those who live in a thin swath of Australia. For a few minutes, those near the center of the eclipse path will see the entire Sun blocked by the Moon, causing the day to become unusually dark. Just before -- and just after -- totality occurs, sunlight may stream between mountains on the Moon's edge creating a diamond ring effect. The next total eclipse of the Sun will occur in November 2013.

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Could you tell the story of human existence in a minute? This thrilling video culls together multiple teasing snippets in an attempt to do just that. And sets it to music. Briefly depicted, from start to finish, is an artistic animation of the Big Bang, a trip across the early universe, the formation of the Earth and Moon, the emergence of multi-celled life and plants, the rise of reptiles and dinosaurs, a devastating meteor strike, the rise of mammals and humans, and finally the rise of modern civilization. The minute movie ends with a flyover of the modern skyscraper and a human standing atop a snow covered mountain. The above video is the latest from the Symphony of Science project.

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This month's New Moon brought a total solar eclipse to parts of planet Earth on November 13 (UT). Most of the total eclipse track fell across the southern Pacific, but the Moon's dark umbral shadow began its journey in northern Australia on Wednesday morning, local time. From along the track, this telescopic snapshot captures the Moon's silhouette in skies over Queensland along the Mulligan highway west of Port Douglas. Almost completely covered, the Sun's disk is seen still surrounded by a hint of the faint solar corona. Planet-sized prominences stretch above the active Sun's edge. Sunlight streaming through gaps in the rugged profile of the lunar limb creates the brilliant but fleeting Baily's Beads.

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On the morning of November 14, the Moon's umbral shadow tracked across northern Australia before heading into the southern Pacific. Captured from a hilltop some 30 miles west of the outback town of Mount Carbine, Queensland, a series of exposures follows the progress of the total solar eclipse in this dramatic composite image. The sequence begins near the horizon. The Moon steadily encroaches on the reddened face of the Sun, rising as the eclipse progresses. At the total phase, lasting about 2 minutes for that location, an otherwise faint solar corona shimmers around the eclipsed disk. Recorded during totality, the background exposure shows a still sunlit sky near the horizon, just beyond a sky darkened by the shadow of the Moon.

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A dark Sun hung over Queensland, Australia on Wednesday morning during a much anticipated total solar eclipse. Storm clouds threatened to spoil the view along the northern coast, but minutes before totality the clouds parted. Streaming past the Moon's edge, the last direct rays of sunlight produced a gorgeous diamond ring effect in this scene from Ellis Beach between Cairns and Port Douglas. Winking out in a moment, the diamond didn't last forever though. The area was plunged into darkness for nearly 2 minutes as the Moon's shadow swept off shore toward Australia's Great Barrier Reef and out into the southern Pacific. Ranging from 1/4000 to 1/15 seconds long, five separate exposures were blended in the image to create a presentation similar to the breathtaking visual experience of the eclipse.

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How massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun, nearly making it the record holder. This star is the brightest object located just above the gas front in the above image. Close inspection of images taken with the Hubble Space Telescope, however, have shown that Pismis 24-1 derives its brilliant luminosity not from a single star but from three at least. Component stars would still remain near 100 solar masses, making them among the more massive stars currently on record. Toward the bottom of the image, stars are still forming in the associated emission nebula NGC 6357. Appearing perhaps like a Gothic cathedral, energetic stars near the center appear to be breaking out and illuminating a spectacular cocoon.

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What's happening in the sky over Monument Valley? A meteor shower. Over the past weekend the Leonid meteor shower has been peaking. The image -- actually a composite of six exposures of about 30 seconds each -- was taken in 2001, a year when there was a much more active Leonids shower. At that time, Earth was moving through a particularly dense swarm of sand-sized debris from Comet Tempel-Tuttle, so that meteor rates approached one visible streak per second. The meteors appear parallel because they all fall to Earth from the meteor shower radiant -- a point on the sky towards the constellation of the Lion (Leo). Although the predicted peak of this year's Leonid meteor shower is over, another peak may be visible early tomorrow morning. By the way -- how many meteors can you identify in the above image?

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Have you ever seen a halo around the Moon? This fairly common sight occurs when high thin clouds containing millions of tiny ice crystals cover much of the sky. Each ice crystal acts like a miniature lens. Because most of the crystals have a similar elongated hexagonal shape, light entering one crystal face and exiting through the opposing face refracts 22 degrees, which corresponds to the radius of the Moon Halo. A similar Sun Halo may be visible during the day. The setting of the above picture is Athens, Greece. The distant planet Jupiter appears by chance on the halo's left. Exactly how ice-crystals form in clouds remains under investigation.

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As the total phase of last week's solar eclipse came to an end, sunlight streaming past the edge of the Moon created the fleeting appearance of a glistening diamond ring in the sky. And while most eclipse watchers did not consider clouds a welcome sight, a view through thin clouds north of Cairns in Queensland, Australia also revealed these remarkable flickering shadow bands. Projected onto the cloud layer, the bands are parallel to the sliver of emerging sunlight. Caused by turbulence in Earth's atmosphere refracting the sliver of sunlight, the narrow bands were captured in this brief, 1/1000th second exposure.

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A cosmic grain of sand left the long and colorful trail across this all-sky view. Its grazing impact with planet Earth's atmosphere began at 71 kilometers per second. With the Milky Way stretching from horizon to horizon, the scene was captured on the night of November 17 from the astronomically popular high plateau at Champ du Feu in Alsace, France. Of course, the earthgrazer meteor belongs to this month's Leonid meteor shower, produced as our fair planet annually sweeps through dust from the tail of periodic Comet Tempel-Tuttle. The shower's radiant point in the constellation Leo is very close to the eastern horizon, near the start of the trail at the lower left. Bright planet Jupiter is also easy to spot, immersed in a faint band of Zodiacal light just below and right of center. The image is part of a dramatic time-lapse video (vimeo here) that began only 7 minutes before the long leonid crossed the sky.

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East of Antares, dark markings sprawl through crowded star fields toward the center of our Milky Way Galaxy. Cataloged in the early 20th century by astronomer E. E. Barnard, the obscuring interstellar dust clouds include B59, B72, B77 and B78, seen in silhouette against the starry background. Here, their combined shape suggests a pipe stem and bowl, and so the dark nebula's popular name is the Pipe Nebula. The deep and expansive view was represents nearly 24 hours of exposure time recorded in very dark skies of the Chilean Atacama desert. It covers a full 10 by 10 degree field in the pronounceable constellation Ophiuchus. The Pipe Nebula is part of the Ophiuchus dark cloud complex located at a distance of about 450 light-years. Dense cores of gas and dust within the Pipe Nebula are collapsing to form stars.

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Barred spiral galaxy NGC 1365 is truly a majestic island universe some 200,000 light-years across. Located a mere 60 million light-years away toward the chemical constellation Fornax, NGC 1365 is a dominant member of the well-studied Fornax galaxy cluster. This sharp color image shows intense star forming regions at the ends of the bar and along the spiral arms, and details of dust lanes cutting across the galaxy's bright core. At the core lies a supermassive black hole. Astronomers think NGC 1365's prominent bar plays a crucial role in the galaxy's evolution, drawing gas and dust into a star-forming maelstrom and ultimately feeding material into the central black hole. Discovered on October 27, the position of a bright supernova is indicated in NGC 1365. Cataloged as SN2012fr, the type Ia supernova is the explosion of a white dwarf star.

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They might look like trees on Mars, but they're not. Groups of dark brown streaks have been photographed by the Mars Reconnaissance Orbiter on melting pinkish sand dunes covered with light frost. The above image was taken in 2008 April near the North Pole of Mars. At that time, dark sand on the interior of Martian sand dunes became more and more visible as the spring Sun melted the lighter carbon dioxide ice. When occurring near the top of a dune, dark sand may cascade down the dune leaving dark surface streaks -- streaks that might appear at first to be trees standing in front of the lighter regions, but cast no shadows. Objects about 25 centimeters across are resolved on this image spanning about one kilometer. Close ups of some parts of this image show billowing plumes indicating that the sand slides were occurring even when the image was being taken.

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