Aurora Over Clouds
10.09.2003

Aurorae usually occur high above the clouds. The auroral glow is created when fast-moving particles ejected from the Sun impact air molecules high in the Earth's atmosphere. An oxygen molecule, for example, will glow in a green light when reacquiring an electron lost during a collision with a solar particle.

An Annular Eclipse of the Sun
24.08.1998

An annular eclipse of the Sun was visible in parts of the Eastern Hemisphere on Saturday. The above picture was taken at that time by a video camera in Mersing on the East Coast of Malaysia and emailed to APOD yesterday from an internet cafe in Kuala Lumpur.

Earth and Moon from Saturn
22.07.2013

You are here. Everyone you've ever known is here. Every human who has ever lived -- is here. Pictured above is the Earth-Moon system as captured by the Cassini mission orbiting Saturn in the outer Solar System.

NGC 6334: The Cats Paw Nebula
18.06.2014

Nebulas are perhaps as famous for being identified with familiar shapes as perhaps cats are for getting into trouble. Still, no known cat could have created the vast Cat's Paw Nebula visible in Scorpius.

Approaching Pluto
27.05.2015

Here comes Pluto. NASA's robotic New Horizons spacecraft is now beyond the orbit of Neptune and closing fast on the Solar System's most famous unexplored world. The featured time lapse video shows...

A Triple Eclipse on Jupiter
2.02.1998

Part of Jupiter is missing. Actually, three parts appear to be missing. In reality though, the three dark spots seen in the above photograph are only shadows. The unusual alignment of three of Jupiter's moons between the Jovian giant and the Sun was imaged last November 10th.

The Cats Paw Nebula
28.06.2006

Nebulae are perhaps as famous for being identified with familiar shapes as perhaps cats are for getting into trouble. Still, no known cat could have created the vast Cat's Paw Nebula visible in Scorpius.

STS 115: Stereo Portrait
30.09.2006

On September 12, astronaut Heidemarie Stefanyshyn-Piper snapped photos of her colleague Joseph Tanner during the STS-115 mission. At the time, the spacesuited pair were working outside the shuttle orbiter Atlantis, some 300 kilometers above planet Earth.

Planetary Nebula NGC 7027 in Infrared
25.03.1998

NGC 7027 is one of the smallest known planetary nebulae. Even so, NGC 7027 is 14,000 times larger than the Earth-Sun distance. Planetary nebula are so named because the first few discovered appeared similar to planets. Planetary nebula are actually dying stars, though, that have recently run out of nuclear fuel.

M1: The Crab Nebula from NOT
20.09.2005

This is the mess that is left when a star explodes. The Crab Nebula, the result of a supernova seen in 1054 AD, is filled with mysterious filaments. The filaments are not only tremendously...