Canon 350D Hap Griffin Baader Mod
30x600sec at iso 1600
30 Darks/Flats/Bias
Orion ED80 with WO 0.8 reducer/flattener
Baader 7nm H alpha filter

Astrophotogallery.org July Challenge Winner

5 hours of H alpha light for a deep exposure of the Crescent Nebula in Cygnus. This shows all the surrounding nebulosity in which NGC6888 is embedded, some of it named and catalogued and some not.

The Crescent Nebula was created by the brightest star in its center. A leading 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. (APOD)

The small open cluster towards the lower left corner is 7th magnitude NGC4996.

June 14, 2008