Halley s Nucleus: An Orbiting Iceberg
5.08.2000

What does a comet nucleus look like? Formed from the primordial stuff of the solar system, it is thought to resemble a very dirty iceberg. But for active comets, telescopic images only reveal the surrounding cloud of gas and dust, the comet's coma, and the characteristic cometary tails.

M27: Not A Comet
2.03.2002

While searching the skies above 18th century France for comets, astronomer Charles Messier diligently recorded this object as number 27 on his list of things which are definitely not comets. So what is it?

The Pelican in the Swan
29.08.2002

The Pelican Nebula, also known as IC 5070, lies about 2,000 light-years away in the high and far-off constellation of Cygnus, the Swan. This picture spans a portion of the magnificent nebula about 30 light-years wide.

Galileo Views Io Eruption
15.08.1996

Io's surface is active. Geyser-like eruptions from volcanoes on this Jovian moon were seen by both Voyager spacecraft in 1979 and were also spotted this year in late June by Galileo's camera from a distance of about 600,000 miles.

Molecular Cloud Barnard 68
2.02.2003

Where did all the stars go? What used to be considered a hole in the sky is now known to astronomers as a dark molecular cloud. Here, a high concentration of dust and molecular gas absorb practically all the visible light emitted from background stars.

Massive Star Forming Region DR21 in Infrared
14.04.2004

Deep in the normally hidden recesses of giant molecular cloud DR21, a stellar nursery has been found creating some of the most massive stars yet recorded. The orbiting Spitzer Space Telescope's Infrared Array Camera opened the window into the cloud last year in mid- infrared light.

The Trifid Nebula from Hubble
18.06.2004

Clouds of glowing gas mingle with lanes of dark dust in the Trifid Nebula, a star forming region toward the constellation of Sagittarius. In the center, the three huge dark dust lanes that give the Trifid its name all come together.

Southern Neptune
10.07.1999

Neptune, the Solar System's outermost gas giant planet, is 30 times farther from the Sun than Earth. Twelve years after a 1977 launch, Voyager 2 flew by Neptune and found surprising activity on a planet that receives only 3 percent as much sunlight as Jupiter.

Small Galaxy NGC 4449
3.05.2007

Grand spiral galaxies often seem to get all the glory. Their newly formed, bright, blue star clusters along beautiful, symmetric spiral arms are guaranteed to attract attention. But small irregular galaxies form stars too, like NGC 4449, located about 12 million light-years away.

In the Heart of the Virgo Cluster
8.07.2008

The Virgo Cluster of Galaxies is the closest cluster of galaxies to our Milky Way Galaxy. The Virgo Cluster is so close that it spans more than 5 degrees on the sky - about 10 times the angle made by a full Moon.