The dead star's shredded remains are called Cassiopeia A, or "Cas A" for short. Cas A is the youngest known supernova remnant in our Milky Way Galaxy and resides 10,000 light-years away in the constellation Cassiopeia. So, the star actually blew up 10,000 years before its light reached Earth in the late 1600s.

This stunning Hubble image of Cas A is allowing astronomers to study the supernova's remains with great clarity, showing for the first time that the debris is arranged into thousands of small, cooling knots of gas. This material eventually will be recycled into building new generations of stars and planets. Our own Sun and planets are constructed from the debris of supernovae that exploded billions of years ago.

This photo shows the upper rim of the supernova remnant's expanding shell. Near the top of the image are dozens of tiny clumps of matter. Each small clump, originally just a small fragment of the star, is tens ofrumes larger than the diameter of our solar system.

The colors highlight parts of the debris where chemical elements are glowing. The dark blue fragments, for example, are richest in oxygen; the red material is rich in sulfur.

The star that created this colorful show was a big one, about 15 to 25 times more massive than our Sun. Massive stars like the one that created Cas A have short lives. They use up their supply of nuclear fuel in tens of millions of years, 1,000 times faster than our Sun. With their fuel exhausted, heavy stars begin a complex chain of events that lead to the final dramatic explosion. Their cores rapidly collapse, releasing an enormous amount of gravitational energy. This sudden burst of energy reverses the collapse and tosses most of the star's mass into space. The ejected material can travel as fast as 45 million miles per hour (72 million kilometers per hour).

The images were taken with the Wide Field and Planetary Camera 2 in January 2000 and January 2002.

Image Credit: NASA and the Hubble Heritage Team (STScI/AURA) Acknowledgment: R. Fesen (Dartmouth) and J. Morse (Univ. of Colorado)

NOTE TO EDITORS: For additional information, please contact Dr. Robert Fesen, Dartmouth College, Dept. of Physics and Astronomy, Hanover, NH 03755, (phone) 603-645-2949, (e-mail) fesen@snr.dartmouth.edu or

Dr. Keith Noll, Hubble Heritage Team, Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, (phone) 410-338-1828, (fax) 410-338-4579, (e-mail) noll@stsci.edu.

Electronic images and additional information are available at:

http://heritage.stsci.edu and
http://oposite.stsci.edu/pubinfo/pr/2002/15 and via links in
http://oposite.stsci.edu/pubinfo/latest.html
http://oposite.stsci.edu/pubinfo/pictures.html
http://hubble.stsci.edu/go/news

The Space Telescope Science Institute (STScI) is operated by the Association of Universities for Research in Astronomy, Inc. (AURA), for NASA, under contract with the Goddard Space Flight Center, Greenbelt, MD. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency (ESA).