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No. 58: Jul-Aug 1988

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Is the earth seeding the rest of the solar system?

We begin with the lead paragraph from a recent letter to Nature from H.J. Melosh;

"Recent evidence that the SNC meteorites originated on Mars raises the question of whether large impacts on Earth may eject rocks that could fall on Mars (or other planets in the Solar System) and, if so whether they might contain spores or some sort of viable microorganisms that would have the opportunity to colonize Mars."

After some computations Melosh concludes:

"It seems likely that the impacts that produced craters on Earth that are greater than 100 km in diameter would each have ejected millions of tons of near-surface rocks carrying viable microorganisms into interplanetary space, much in the form of boulders large enough to shield those organisms from ultraviolet radiation, low-energy cosmic rays, and even galactic cosmic rays. Under such circumstances spores might remain viable for long periods of time."

(Melosh, H.J.; "The Rocky Road to Panspermia," Nature, 332:687, 1988.)

Comment. Next we need a reasonable mechanism that spreads life through interstellar space. Light pressure, that's it; and the idea is over a century old! Incidentally, SNC is short for Shergottites, Nakhalites, Chassignites; all rare classes of meteorites.

From Science Frontiers #58, JUL-AUG 1988. 1988-2000 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