Astronomy Picture Of the Day (APOD)South Pole Star Trails
No star dips below the horizon and the Sun never climbs above it in this remarkable Lewin's Challenge image of 24 hour long star trails. Showing all the trails as complete circles, such an image could be achieved only from two places on planet Earth.
The Milky Way Over Monument Valley
You don't have to be at Monument Valley to see the Milky Way arch across the sky like this -- but it helps. Only at Monument Valley USA would you see a picturesque foreground that includes these iconic rock peaks called buttes.
Curiosity Before Mars: Seven Minutes of Terror
Next week at this time, there may be an amazing new robotic explorer on Mars. Or there may be a new pile of junk. It all likely depends on many things going correctly in the minutes after the Mars Science Laboratory mission arrives at Mars and attempts to deploy the Curiosity rover from orbit.
Ash and Lightning Above an Icelandic Volcano
Why did the picturesque 2010 volcanic eruption in Iceland create so much ash? Although the large ash plume was not unparalleled in its abundance, its location was particularly noticeable because it drifted across such well-populated areas.
Star Cluster R136 Bursts Out
In the center of star-forming region 30 Doradus lies a huge cluster of the largest, hottest, most massive stars known. These stars, known collectively as star cluster R136, were captured above in visible light by the newly installed Wide Field Camera peering though the recently refurbished Hubble Space Telescope.
Trails in the Morning Sky
Brilliant Venus and bright Jupiter still rise together before dawn. The peaceful waters by a small lakeside house near Stuttgart, Germany reflect their graceful arcing trails in this composited series of exposures, recorded on the morning of July 26.
High Energy Stereoscopic System II
The largest of its kind, the High Energy Stereoscopic System (H.E.S.S.) II telescope stands in the foreground of this photo. Tilted horizontally it reflects the inverted landscape of the Namibian desert in a segmented mirror 24 meters wide and 32 meters tall, equal in area to two tennis courts.
The Tulip in the Swan
Framing a bright emission region this telescopic view looks out along the plane of our Milky Way Galaxy toward the nebula rich constellation Cygnus the Swan. Popularly called the Tulip Nebula the glowing cloud of interstellar gas and dust is also found in the 1959 catalog by astronomer Stewart Sharpless as Sh2-101.
Pink Aurora Over Crater Lake
Why is this aurora strikingly pink? When photographing picturesque Crater Lake in Oregon, USA last month, the background sky lit up with auroras of unusual colors. Although much is known about the physical mechanisms that create auroras, accurately predicting the occurrence and colors of auroras remains a topic of investigation.
South Polar Vortex Discovered on Titan
What's happening over the south pole of Titan? A vortex of haze appears to be forming, although no one is sure why. The above natural-color image shows the light-colored feature. The vortex was found on images taken last month when the robotic Cassini spacecraft flew by the unusual atmosphere-shrouded moon of Saturn.