Spider and Fly Nebula./Courtesy of Dave Bodington

This is a photo of a spider and a fly nebula taken for a total of 20 hours at the end of January in Berkshire, England. The spider-shaped gas cloud in the center of the photo is called the "IC 417" emission nebula. An emission nebula is one that emits light of various wavelengths. The small fly-shaped cloud on the left side of the photo is known as "NGC 1931" and is both an emission nebula and a "reflection nebula," which glows brightly by reflecting light emitted from stars. Behind the spider nebula, interstellar gas and dust are spreading, glowing red.