NGC 6888 The Crecsent Nebula  -  9.18.2007
Image Capture Details

Optics:  Meade LX200 14 GPS @ F/2 with HyperStar
Mount: Meade
Camera: Canon Digital Rebel
Filters: none
Exposure:  265 X 20 Seconds = 3+ Hours
ISO 800
Time: 10:50 PM EST - 1:05AM EST
Location: Waldwick, NJ
© 2007 David A. Trapani
MetropolitanSkies.com
All Rights Reserved
1  A rapidly expanding, luminous shell of gas that surrounds the
Wolf-Rayet star WR 136 in the constellation Cygnus. The Crescent
Nebula started to form about 250,000 years ago as the central star
began shedding its outer envelope in a strong stellar wind. As this
wind rammed into the surrounding interstellar medium, it compacted
it and sent shock waves into it, resulting in a series of shells, which
ultraviolet radiation from WR 136 subsequently ionized and made
visible.

1http://www.daviddarling.info/encyclopedia/C/Crescent_Nebula.html
Click image for
higher resolution