Home Page Science Frontiers

No. 68: Mar-Apr 1990

Issue Contents

Other pages

Other Interesting Sites











Double Image Of Cresent Moon

November 24, 1989. Knoxville, Tennessee.

"Conditions: Clear sky (no clouds, but a slight haze). Waning moon was approx. 60 above the horizon, air temperature 33F.

Double image of crescent moon
"I came out of the house about 6:25 AM to perform a task and, being an amateur astronomer, I looked up at the sky to see what was visible. I noticed the crescent of the waning moon appeared as a double crescent. My eyes kept trying to resolve it into a single image, but it wouldn't resolve. I then looked at several other light sources (radio tower, porch light, & street light) and determined that my vision was probably fine, as these objects appeared as single images. Looking back at the moon, it still appeared as a double image. I covered the right eye and I still saw a double image. I did the same with the left eye and got the same results. I then held out my right arm and extended my thumb to cover one crescent. I saw only one image that way. I moved my thumb and the image was again doubled. I concluded that I was viewing refracted images of the moon.

"Conditions prevented continuous observation, but I was able to return approximately every five minutes. By 6:55 AM the sky was brightening and there was only a single lunar crescent."

(Miles, Bob; "Double Image of Crescent Moon," Teknowledgy Press, 1989. Cr. D.K. Hackett)

Comment. Although refraction is usually blamed for such double images, the different layers of air, with different refractive indices, would normally be disposed horizontally, not at the angle shown in the illustration.

From Science Frontiers #68, MAR-APR 1990. 1990-2000 William R. Corliss

Science Frontiers Sourcebook Project Reviewed in:


  • "A sourcebook of unexplained phenomena is therefore a valuable addition to a collection of scientific literature. William R. Corliss has provided this in the past with his source books of scientific anomalies in several subjects, and now he has provided it for astronomy. He has done an excellent job of collecting and editing a large amount of material, taken in part from scientific journals and in part from scientific reporting in the popular or semi-scientific press." -- "The Mysterious Universe: A Handbook of Astronomical Anomalies", reviwed by Thomas Gold, Cornell University, in Icarus, vol.41, 1980

  • "An interesting, systematic presentation of unusual weather [..] This book is recommended for a general audience" --"Corliss, William R., Tornados, Dark Days, Anomalous Precipitation, and Related Weather Phenomena, Sourcebook Project, 1983.", revieweed in Choice, September 1983
  • "..the science is necessarily somewhat speculative, but Corliss's symthesis is based on reputable sources." -- "Corliss, William R. (Compiler). Lightning, Auroras, Nocturnal Lights, and Related Luminous Phenomena" reviwed by Joseph M. Moran, Univ. of Wisconsin in Science Books and Films, Sep/Oct 1983

  • "Before opening the book, I set certain standards that a volume which treads into dangerous grounds grounds like this must meet. The author scrupulously met, or even exceeded those standards. Each phenomenon is exhaustively documented, with references to scientific journals [..] and extensive quotations" -- "Book Review: The moon and planets: a catalog of astronomical anomalies", The Sourcebook Project, 1985., Corliss, W. R., Journal of the Royal Astronomical Society of Canada, Vol. 81, no. 1 (1987), p. 24., 02/1987