Science Frontiers ONLINE No. 39: May-Jun 1985 Issue Contents

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LDE PROBLEM STILL UNSOLVED

LDEs (Long-Delayed Radio Echoes) have been known for over 50 years. Radio hams, in particular, will on rare occasions hear their transmissions repeated several seconds later. Various theories have been proposed, including: roundthe-world propagation; trapping in ionospheric ducts; reflections from distant plasma clouds; and beam-plasma interactions. R.J. Vidmar and F.W. Crawford, at Stanford, have been studying the LDE problem experimentally and theoretically and conclude that we still don't know which of the proposed mechanisms are valid.

(Vidmar, F.R., and Crawford, F.W.; "Long-Delayed Radio Echoes: Mechanisms and Observations," Journal of Geophysical Research, 90:1523, 1985.)

From Science Frontiers #39, MAY-JUN 1985. © 1985-2000 William R. Corliss

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Science Frontiers Sourcebook Project Reviewed in: Icarus: Volume 41, Issue 3, p. 470-470 1984, Vol.56:3, P.615 1983, Vol.58:3 June 1984, Vol.60:3 Dec 1984, Vol.72:3 Dec 1987 Journal of the Royal Astronomical Society of Canada, Vol. 81, no. 1 1987 American Journal of Physics, Volume 52, Issue 8, p. 764 August 1984 Quotes "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