Todays pic is a rather splendid view of my favourite type of astronomical feature, a nebula.
A Crescent Nebula Star Field
What caused the Crescent Nebula? Looking like an emerging space cocoon, the Crescent Nebula, visible on the right, was created by the brightest star in its center. A leading progenitor hypothesis has the Crescent Nebula beginning to form about 250,000 years ago. At that time, the massive central star had evolved to become a Wolf-Rayet star (WR 136), shedding its outer envelope in a strong stellar wind, ejecting the equivalent of our Sun's mass every 10,000 years. This wind impacted surrounding gas left over from a previous phase, 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. Star WR 136 will probably undergo a supernova explosion sometime in the next million years.
Credit & Copyright: T. A. Rector (NRAO), NOAO, AURA, NSF
A higher resolution version of this pic can be found here, this is a 293K Jpeg image.
Previous Pic Of The Day posts
14th Apr 03
12th Apr 03
11th Apr 03
09th Apr 03
08th Apr 03
03rd Apr 03
30th Mar 03
A Crescent Nebula Star Field
What caused the Crescent Nebula? Looking like an emerging space cocoon, the Crescent Nebula, visible on the right, was created by the brightest star in its center. A leading progenitor hypothesis has the Crescent Nebula beginning to form about 250,000 years ago. At that time, the massive central star had evolved to become a Wolf-Rayet star (WR 136), shedding its outer envelope in a strong stellar wind, ejecting the equivalent of our Sun's mass every 10,000 years. This wind impacted surrounding gas left over from a previous phase, 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. Star WR 136 will probably undergo a supernova explosion sometime in the next million years.
Credit & Copyright: T. A. Rector (NRAO), NOAO, AURA, NSF
A higher resolution version of this pic can be found here, this is a 293K Jpeg image.
Previous Pic Of The Day posts
14th Apr 03
12th Apr 03
11th Apr 03
09th Apr 03
08th Apr 03
03rd Apr 03
30th Mar 03
