1999 Leonid Fireball
2.12.1999

Most Leonid meteoroids, the bits of comet debris which produce the annual Leonid meteor shower, range from a mere millimeter to a centimeter in diameter. Yet these cosmic grains of sand and gravel can put on quite a spectacular show. How can something so small generate so much light?

Aurora Through a Moonlit Sky
2.11.1999

A night sky can glow in fascinating ways. Through a clearing in the woods, the pictured sky above Alaska shines by reflected light from a nearby city, by the brightness of the Moon, and by aurora.

The Cat's Eye Nebula
31.10.1999

Three thousand light-years away, a dying star throws off shells of glowing gas. This image from the Hubble Space Telescope reveals The Cat's Eye Nebula to be one of the most complex planetary nebulae known.

APOD: 2007 August 1- Unusual Cratering on Saturns Dione
1.08.2007

Why does one half of Dione have more craters than the other? Start with the fact that Saturn's moon Dione always has one side that faces Saturn, and always has one side that faces away. This is similar to Earth's Moon.

June s Young Crescent Moon
7.06.2008

Serene skyviews were enjoyed across planet Earth earlier this week with a young crescent Moon low in the western sky just after sunset. Recorded on June 4, this colorful example includes a quiet beach in the foreground with the city lights of Lisbon, Portugal, and the Sintra Mountains along the horizon.

Aurora Over Norway
20.09.2010

Auroras can make spectacular sights. Photographed above last weekend, flowing multi-colored auroras helped illuminate a busy sky above TromsЬ, Norway. Besides the spectacular aurora pictured above, the photographer caught three satellites streaks, one airplane streak, and a friend trying to capture the same sight.

IC 1396: Emission Nebula in Cepheus
5.08.2012

Stunning emission nebula IC 1396 mixes glowing cosmic gas and dark dust clouds in the high and far off constellation of Cepheus. Energized by the bright, bluish central star seen here, this star forming region sprawls across hundreds of light-years -- spanning over three degrees on the sky while nearly 3,000 light-years from planet Earth.

Earths Richat Structure
19.05.2013

What on Earth is that? The Richat Structure in the Sahara Desert of Mauritania is easily visible from space because it is nearly 50 kilometers across. Once thought to be an impact crater, the Richat Structure's flat middle and lack of shock-altered rock indicates otherwise.

Night at the Drive In
20.09.2013

Colorful stars trail through this late summer, night skyscape from Cape Cod, Massachusetts. The picture was composed by stacking 12 consecutive 1 minute long digital camera exposures to follow the trails, a reflection of our fair planet's daily rotation.

Phobos 360
25.12.2013

What does the Martian moon Phobos look like? To better visualize this unusual object, images from ESA's Mars Express orbiter have been combined into a virtual rotation movie. The rotation is actually a digital illusion -- tidally-locked Phobos always keeps the same face toward its home planet, as does Earth's moon.