Cassiopeia A: supernova remnant, shell type (optical view) | 19/08/1999 | ||
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Cas
A is the remnant of a star that exploded about 300 years ago. The X-ray
image shows an expanding shell of hot gas produced by the explosion. This
gaseous shell is about 10 light years in diameter, and has a temperature
of about 50 million degrees. |
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Image Credit: MDM Observatory. | |||
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Two shock waves are visible: a fast outer shock and a slower inner shock. The inner shock wave is believed to be due to the collision of the ejecta from the supernova explosion with a circumstellar shell of material, heating it to a temperature of ten million degrees. The outer shock wave is analogous to an awesome sonic boom resulting from this collision. | ![]() |
The optical image of Cas A shows matter with a temperature of about ten thousand degrees. Some of these wisps contain high concentrations of heavy elements and are thought to be dense clumps of ejected stellar material. | |
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