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06 Feb ' 22:50
2012 February 7
The Belt of Venus Over Mercedes, Argentina Luis Argerich 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 or orange. 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. Below the Belt of Venus, the atmosphere appears more dark because no sunlight reaches it. The Belt of Venus can be seen from any location with a clear horizon. Pictured above last month over Mercedes, Argentina, a panoramic vista featuring the Belt of Venus was digitally stitched together from 16 smaller images. The belt is frequentlycaughtbyaccidentinotherphotographs
open space -
06 Feb ' 10:59
Best of APOD: The Orion Nebulabelt venus -
05 Feb ' 22:32
2012 February 6
Dust of the Orion Nebula Nicolás Villegas What surrounds a hotbed of star formation? In the case of the Orion Nebula -- dust. The entire Orion field, located about 1600 light years away, is inundated with intricate and picturesque filaments of dust. Opaque to visible light, dust is created in the outer atmosphere of massive cool stars and expelled by a strong outer wind of particles. The Trapezium and other forming star clusters are embedded in the nebula. The intricate filaments of dust surrounding M42 and M43 appear brown in the above image, while central glowing gas is highlighted in red. Over the next few million years much of Orion's dust will be slowly destroyed by the very stars now being formed, or dispersed into the Galaxy.
open space -
05 Feb ' 01:47
2012 February 5
Lunation Image Credit & Copyright: António Cidadão Our Moon's appearance changes nightly. This time-lapse sequence shows what our Moon looks like during a lunation, a complete lunar cycle. As the Moon orbits the Earth, the half illuminated by the Sun first becomes increasingly visible, then decreasingly visible. The Moon always keeps the same face toward the Earth. The Moon's apparent size changes slightly, though, and a slight wobble called a libration is discernible as it progresses along its elliptical orbit. During the cycle, sunlight reflects from the Moon at different angles, and so illuminates different features differently. A full lunation takes about 29.5 days, just under a month (moon-th).
APOD in India: APOD editor to speak in Delhi on Feb. 12 (registration requiredred hunter -
04 Feb ' 01:25
2012 February 4
Comet Garradd and M92 Image Credit & Copyright: Rolando Ligustri (CARA Project, CAST Sweeping slowly through the constellation Hercules, Comet Garradd (C2009/P1) passed with about 0.5 degrees of globular star cluster M92 on February 3. Captured here in its latest Messier moment, the steady performer remains just below naked-eye visibility with a central coma comparable in brightness to the dense, well-known star cluster. The rich telescopic view from New Mexico's, early morning skies, also features Garradd's broad fan shaped dust tail and a much narrower ion tail that extends up and beyond the right edge of the frame. Pushed out by the pressure of sunlight, the dust tail tends to trail the comet along its orbit while the ion tail, blown by the solar wind, streams away from the comet in the direction opposite the Sun. Of course, M92 is over 25,000 light-years away. Comet Garradd is 12.5 light-minutes from planet Earth, arcing above the ecliptic plane
Sunday's Childe -
03 Feb ' 02:30
2012 February 3
Inside the Eagle Nebula Credit: Far-infrared: ESA/Herschel/PACS/SPIRE/Hill, Motte, HOBYS Key Programme Consortium; X-ray: ESA/XMM-Newton/EPIC/XMM-Newton-SOC/Boulanger In 1995, a now famous picture from the Hubble Space Telescope featured Pillars of Creation, star forming columns of cold gas and dust light-years long inside M16, the Eagle Nebula. This remarkable false-color composite image revisits the nearby stellar nursery with image data from the orbiting Herschel Space Observatory and XMM-Newton telescopes. Herschel's far infrared detectors record the emission from the region's cold dust directly, including the famous pillars and other structures near the center of the scene. Toward the other extreme of the electromagnetic spectrum, XMM-Newton's X-ray vision reveals the massive, hot stars of the nebula's embedded star cluster. Hidden from Hubble's view at optical wavelengths, the massive stars have a profound effect, sculpting and transforming the natal gas and dust structures with their energetic winds and radiation. In fact, the massive stars are short lived and astronomers have found evidence in the image data pointing to the remnant of a supernova explosion with an apparent age of 6,000 years. If true, the expanding shock waves would have destroyed the visible structures, including the famous pillars. But because the Eagle Nebula is some 6,500 light-years distant, their destruction won't be witnessed for hundreds of years.
a Messier moment -
02 Feb ' 15:04
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02 Feb ' 00:30
2012 February 2
La Silla Star Trails North and South Image Credit & Copyright: Alexandre Santerne (Laboratoire d'Astrophysique de Marseille / Observatoire de Haute Provence) Fix your camera to a tripod and you can record graceful trails traced by the stars as planet Earth rotates on its axis. If the tripod is set up at ESO's La Silla Observatory, high in the Atacama desert of Chile, your star trails would look something like this. Spanning about 4 hours on the night of January 24, the image is actually a composite of 250 consecutive 1-minute exposures, looking toward the north. The North Celestial Pole, at the center of the star trail arcs, is just below the horizon in this southern hemisphere perspective. In the foreground, the polished 15-meter diameter dish antenna of the Swedish-ESO Submillimeter Telescope (now decommissioned) shows star trails toward the south by reflection. Sweeping around the South Celestial Pole, the distorted arcs of those stars appear underneath the southern horizon in the focusing dish's inverted view. Right of the dish is the dome of the observatory's 3.6 meter telescope, home to the planet hunting HARPS spectrograph.
Eagle Nebula -
01 Feb ' 10:52
Credit & Copyright: visible that night puts the picturesque scene in context. Why the sky did not
APOD in India: APOD editor to speak in Delhi on Feb. 12 (registration required -
31 Jan ' 23:35
2012 February 1
Red Aurora Over Australia Alex Cherney (Terrastro, TWAN Why would the sky glow red? Aurora. Last week's solar storms, emanating mostly from active sunspot region 1402, showered particles on the Earth that excited oxygen atoms high in the Earth's atmosphere. As the excited element's electrons fell back to their ground state, they emitted a red glow. Were oxygen atoms lower in Earth's atmosphere excited, the glow would be predominantly green. Pictured above, this high red aurora is visible just above the horizon last week near Flinders, Victoria, Australia. The sky that night, however, also glowed with more familiar but more distant objects, including the central disk of our Milky Way Galaxy on the left, and the neighboring Large and Small Magellanic Cloud galaxies on the right. A time-lapse video highlighting auroras visible that night puts the picturesque seen in context. Why the sky did not also glow green remains unknown.
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