Comet Hale-Bopp Against a Blue Sky

This photo was taken at f2.8 with a 40 second exposure time and ASA 1000 color print film on April 21, 1997, at about 920 PM. The daytime sky is blue because the molecules in the air scatter blue light more effectively than red light. A moonlit sky should be blue for the same reason, but our color vision doesn't work at low light levels. However, the camera has no such problem, and, under the right conditions, it will show a blue night sky, as in this photo.

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Last modified: August 19,1997. Send comments to