Hot Gas and Dark Matter
4.04.1999

Is the gravity of the galaxies seen in this image high enough to contain the glowing hot gas? Superposed on an optical picture of a group of galaxies is an image taken in X-ray light.

Hot Gas and Dark Matter
2.09.1995

Is the gravity of the above galaxies high enough to contain the glowing hot gas? Superposed on an optical picture of a group of galaxies is an image taken in X-ray light. The X-ray...

Callisto: Dark Smashed Iceball
6.09.1995

Callisto is a dirty battered world, showing the most beaten surface of Jupiter's major moons. Made of a rocky core covered by fractured ice, Callisto's past collisions with large meteors are evident as large craters surrounded by concentric rings.

A Dark and Stormy Night
30.10.2003

It was a dark and stormy night. But on August 29th the red planet Mars, near it's closest approach to Earth in almost 60,000 years, shone brightly in the sky against a background of stars in the constellation Aquarius.

Dark Sky, Bright Sun
13.02.1999

In low Earth orbit there is not enough atmosphere to diffuse and scatter sunlight, so shadows are black and the sky is dark - even when the Sun shines. The harsh lighting produced this dramatic...

Cosmic Ripples Implicate Dark Universe
29.05.2002

What may appear fuzzy to some makes things crystal clear to others. The cosmic microwave background radiation emanating from the universe could only have the above fuzzy pattern if it contained clear amounts of dark matter and dark energy.

Dark Sky, Bright Sun
2.09.1997

In low Earth orbit there is not enough atmosphere to diffuse and scatter sunlight, so shadows are black and the sky is dark - even when the Sun shines. The harsh lighting produced this dramatic...

The Dark River to Antares
9.08.2004

Connecting the Pipe Nebula to the bright star Antares is a flowing dark cloud nicknamed the Dark River. The murkiness of the Dark River is caused by absorption of background starlight by dust, although the nebula contains mostly hydrogen and molecular gas.

The Chameleon's Dark Nebulae
15.07.2009

The Chameleon is a small constellation near the south celestial pole. Boasting no bright stars, it blends inconspicuously with the starry southern sky. But, taken in dark skies over Namibia, this image reveals a stunning aspect of the shy constellation -- a field of dusty nebulae and colorful stars.

The Dark River to Antares
3.06.2008

Connecting the Pipe Nebula to the bright star Antares is a flowing dark cloud nicknamed the Dark River. The murkiness of the Dark River is caused by absorption of background starlight by dust, although the nebula contains mostly hydrogen and molecular gas.