APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
At the Edge of the Crescent Nebula
Explanation: The Crescent Nebula is a rapidly expanding shell of gas surrounding a dying star. In this recently released image by the Hubble Space Telescope , a bright dynamic part of the nebula three light-years across is shown in representative color. The Crescent Nebula began to form about 250,000 years ago as central Wolf-Rayet star WR 136 began to shed its outer envelope in a strong stellar wind , expelling the equivalent of our Sun's mass every 10,000 years. This wind has been impacting surrounding interstellar gas , compacting it into a series of complex shells, and lighting it up. The Crescent Nebula , also known as NGC 6888, lies about 4,700 light-years away in the constellation of Cygnus and can only be seen through a telescope. Star WR 136 will probably undergo a supernova explosion sometime in the next million years.
| Date | August 2, 2000 |
|---|---|
| Credit | Credit: Brian D. Moore ( ASU ) et al., WFPC2 , HST , NASA |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |