Starship Asterisk*

http://apod.nasa.gov/apod/calendar/S_100222.jpg Galaxy Group Hickson 31 Explanation: Will the result of these galactic collisions be one big elliptical galaxy ? Quite possibly, but not for another billion years. Pictured above , several of the dwarf galaxies of in the Hickson Compact Group 31 are s...

http://apod.nasa.gov/apod/calendar/S_100221.jpg NGC 2440: Cocoon of a New White Dwarf Explanation: Like a butterfly , a white dwarf star begins its life by casting off a cocoon that enclosed its former self. In this analogy, however, the Sun would be a caterpillar and the ejected shell of gas would...

http://apod.nasa.gov/apod/calendar/S_100220.jpg Geostationary Highway Explanation: Put a satellite in a circular orbit about 42,000 kilometers from the center of the Earth (36,000 kilometers or so above the surface) and it will orbit once in 24 hours. Because that matches Earth's rotation period, i...

http://apod.nasa.gov/apod/calendar/S_100219.jpg WISE Infrared Andromeda Explanation: This sharp, wide-field view features infrared light from the spiral Andromeda Galaxy (M31) . Dust heated by Andromeda's young stars is shown in yellow and red, while its older population of stars appears as a bluis...

http://apod.nasa.gov/apod/calendar/S_100218.jpg Vesta Near Opposition Explanation: Main belt asteroid 4 Vesta is at its brightest now. The small world is near opposition (opposite the Sun in the sky) and closest to Earth. But even at its brightest, Vesta is just too faint to spot with the naked-eye...

http://apod.nasa.gov/apod/calendar/S_100217.jpg An Unusually Smooth Surface on Saturns Calypso Explanation: Why is this moon of Saturn so smooth? This past weekend, humanity's Saturn-orbiting Cassini spacecraft passed as close to Saturn's small moon Calypso as it ever has, and imaged the small moon...

http://apod.nasa.gov/apod/calendar/S_100216.jpg Dark Shuttle Approaching Explanation: What's that approaching? Astronauts on board the International Space Station first saw it far in the distance. Soon it enlarged to become a dark silhouette . As it came even closer, the silhouette appeared to be a...

http://apod.nasa.gov/apod/calendar/S_100215.jpg Cassini Spacecraft Crosses Saturn's Ring Plane Explanation: If this is Saturn, where are the rings? When Saturn's "appendages" disappeared in 1612, Galileo did not understand why. Later that century, it became understood that Saturn 's unusu...

http://apod.nasa.gov/apod/calendar/S_100214.jpg Field of Rosette Explanation: What surrounds the florid Rosette nebula? To better picture this area of the sky, the famous flowery emission nebula on the far right has been captured recently in a deep and dramatic wide field image that features severa...

http://apod.nasa.gov/apod/calendar/S_100213.jpg Waterway to Orbit Explanation: The 32nd shuttle mission to the International Space Station, STS-130 , left planet Earth on February 8. Its early morning launch to orbit from Kennedy Space Center's pad 39A followed the long, graceful, eastward arc seen...

http://apod.nasa.gov/apod/calendar/S_100212.jpg Teide Sky Trails Explanation: The snow capped Teide volcano is reflected in a pool of water in this nearly symmetric night sky view from the Canary Island Tenerife. Bright north star Polaris stands above the peak in an exposure that also captures the ...

http://apod.nasa.gov/apod/calendar/S_100211.jpg Star Cluster M34 Explanation: This pretty open cluster of stars, M34, is about the size of the Full Moon on the sky. Easy to appreciate in small telescopes, it lies some 1,800 light-years away in the constellation Perseus . At that distance, M34 physi...

http://apod.nasa.gov/apod/calendar/S_100210.jpg Sakurajima Volcano with Lightning Explanation: Why does a volcanic eruption sometimes create lightning? Pictured above, the Sakurajima volcano in southern Japan was caught erupting early last month. Magma bubbles so hot they glow shoot away as liquid ...

http://apod.nasa.gov/apod/calendar/S_100209.jpg Night Launch of the Space Shuttle Endeavour Explanation: Sometimes, the space shuttle launches at night. Pictured above , the space shuttle Endeavour lifted off in yesterday's early morning hours from Launch Pad 39A in Kennedy Space Center , Florida ,...

http://apod.nasa.gov/apod/calendar/S_100208.jpg A Sun Halo Over Cambodia Explanation: Have you ever seen a halo around the Sun? 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...

http://apod.nasa.gov/apod/calendar/S_100207.jpg The Einstein Cross Gravitational Lens Explanation: Most galaxies have a single nucleus -- does this galaxy have four? The strange answer leads astronomers to conclude that the nucleus of the surrounding galaxy is not even visible in this image . The c...

http://apod.nasa.gov/apod/calendar/S_100206.jpg Hong Kong Sky Explanation: This remarkable scene combines multiple exposures recorded on the evening of January 18th from a waterside perspective in Hong Kong, China . It follows a young crescent Moon , with brilliant planet Jupiter to its left, as th...

http://apod.nasa.gov/apod/calendar/S_100205.jpg Dust Storm on Mars Explanation: It's spring for the northern hemisphere of Mars and spring on Mars usually means dust storms . So the dramatic brown swath of dust (top) marking the otherwise white north polar cap in this picture of the Red Planet is n...

http://apod.nasa.gov/apod/calendar/S_100204.jpg Stardust in Perseus Explanation: This cosmic expanse of dust, gas, and stars covers close to 3 degrees on the sky in the heroic constellation Perseus . Right of center in the gorgeous skyscape is the dusty blue reflection nebula NGC 1333 , about 1,000...

http://apod.nasa.gov/apod/calendar/S_100203.jpg P2010 A2: Unusual Asteroid Tail Implies Powerful Collision Explanation: What is this strange object? First discovered on ground based LINEAR images on January 6, the object appeared unusual enough to investigate further with the Hubble Space Telescope...

http://apod.nasa.gov/apod/calendar/S_100202.jpg Mars and a Colorful Lunar Fog Bow Explanation: Even from the top of a volcanic crater, this vista was unusual. For one reason, Mars was dazzlingly bright two weeks ago, when this picture was taken, as it was nearing its brightest time of the entire ye...

http://apod.nasa.gov/apod/calendar/S_100201.jpg Shepherd Moon Prometheus from Cassini Explanation: Another moon of Saturn has been imaged in detail by the Cassini spacecraft. Orbiting Saturn since 2004, the robotic Cassini got its closest look yet at Saturn's small moon Prometheus last week. Visibl...

http://apod.nasa.gov/apod/calendar/S_100131.jpg The Mysterious Voynich Manuscript Explanation: The ancient text has no known title, no known author, and is written in no known language: what does it say and why does it have many astronomy illustrations? The mysterious book was once bought by an emp...

http://apod.nasa.gov/apod/calendar/S_100130.jpg Messier 88 Explanation: Charles Messier described the 88th entry in his 18th century catalog of Nebulae and Star Clusters as a spiral nebula without stars. Of course the gorgeous M88 is now understood to be a galaxy full of stars, gas, and dust, not u...

http://apod.nasa.gov/apod/calendar/S_100129.jpg Mars Opposition 2010 Explanation: Mars is at opposition tonight , opposite the Sun in planet Earth's sky. Of course, it will be easy to spot because Mars appears close to tonight's Full Moon, also opposite the Sun in Earth's night sky in the constella...