Opposition light (w-838-05)
In gallery: Photos of the month (2006)
Related photos: Astronomy
The opposition light (German: gegenschein) is clearly visible at the center of this 20-minute exposure of the night sky over New Mexico (USA). With a bit of effort the entire zodiacal light bridge can be seen running from the top left to lower right of the frame. The Milky Way is to the upper right. Note also the green airglow at lower left.
The opposition light, which is backscattered sunlight from interplanetary dust, is extremely faint and you must be in a very dark area away from cities to have a chance to observe it. As the photo shows the opposition light is fairly broad and diffuse.
This photo was made around 2:00 AM MDT on October 1, with a Nikon FE and Fujichrome Provia 400F film (push-processed one stop to 800 ISO), with the camera piggy-backed on an 8" telescope. The exposure time was 20 minutes, and the lens was a 16mm full-frame fisheye at f/2.8.