Home Page Science Frontiers

No. 80: Mar-Apr 1992

Issue Contents

Other pages

Other Interesting Sites











Anomalous Optical Events In The Upper Atmosphere

A photodiode was recently lofted to high altitudes (over 400 kilometers) in an experiment to measure the optical power of lightning. During the 10-minute flight, more than 500 lightning-related events were recorded over that part of the globe visible from the rocket's altitude.

"Among these is a class of about 23 events all having an anomalous signature, with obvious clustering of optical impulses or continuous emissions, and resulting durations of several hundred milliseconds. Such durations are much longer than typical for lightning-related events recorded at the rocket, which are more frequent overall. Every anomalous optical event (AOE) was accompanied by broadband VLF signals of a distinctive character...In considering possible sources above 30 km we find that the AOEs do not seem to resemble other natural optical phenomena, such as meteors which burn up well above 30 km in the mid-latitude atmosphere."

(Li, Ya Qi, et al; "Anomalous Optical Events Detected by Rocket-Borne Sensor in the WIPP Campaign," Journal of Geo physical Research, 96:1315, 1991. Cr. C. Rush.)

Comment. Apparently these anomalous "flashes" have not yet been detected from the ground. The implication is that there are many more high-altitude electrical discharges than scientists expect or can account for.

From Science Frontiers #80, MAR-APR 1992. 1992-2000 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