Molecular Torus Surrounds Black Hole
8.09.2004

Why do some black hole surroundings appear brighter than others? In the centers of active galaxies, supermassive black holes at least thousands of times the mass of our Sun dominate. Many, called Seyfert Type I, are very bright in visible light. Others, called Seyfert Type II, are rather dim.

Hydrogen in M51
11.06.2010

Perhaps the original spiral nebula, M51 is a large galaxy, over 60,000 light-years across, with a readily apparent spiral structure. Also cataloged as NGC 5194, M51 is a part of a well-known interacting galaxy pair, its spiral arms and dust lanes clearly sweeping in front of companion galaxy NGC 5195 (top).

Millions of Stars in Omega Centauri
16.04.2002

Pictured above is the largest ball of stars in our Galaxy. About 10 million stars orbit the center of this globular cluster - named Omega Centauri - as this giant globular cluster orbits our Galactic center.

A Supernova in the Whirlpool
21.04.1996

In 1994, a new star in a distant galaxy was seen by amateur astronomers, who alerted the world to their discovery of a supernova. Near the nucleus of spiral galaxy M51, popularly known...

ASCA X-Ray Observatory
20.02.1996

Today marks the third anniversary of the launch of the Advanced Satellite for Cosmology and Astrophysics (ASCA; renamed from Astro D when launched). ASCA, seen here superposed on galaxy M31, is a Japanese satellite for which NASA has provided some scientific equipment. ASCA carries four large-area X-ray telescopes.

In the Center of 30 Doradus
24.05.1996

In the center of 30 Doradus lies a huge cluster of the largest, hottest, most massive stars known. The center of this cluster, known as R136, is boxed in the upper right portion of the above picture.

The Magellanic Stream
26.08.1998

Spanning the sky behind the majestic Clouds of Magellan is an unusual stream of gas: the Magellanic Stream. The origin of this gas might hold a clue to origin and fate of our Milky Way's most famous satellite galaxies: the LMC and the SMC.

A Supernova Starfield
9.02.1999

Bright stars don't last forever. A bright star similar to others in this field exploded in a spectacular supernova that was witnessed on Earth in 1987. The result is visible even today as unusual rings and glowing gas. The above picture is a composite of recent images taken over several years.

The Frothy Milky Way
9.10.1999

Astronomers have discovered that looking at dust along the plane of our Milky Way Galaxy is a bit like looking into a frothy glass of beer. The dust between stars in our galaxy appears...

Goat Aurora Over Greenland
3.10.2012

Sometimes it's hard to believe what you see in the sky. During the Shelios Expedition to Greenland in late August, even veteran sky enthusiasts saw auroras so colorful, so fast changing, and so unusual in form that they could remember nothing like it.