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Science Frontiers ONLINE No. 112: Jul-Aug 1997 |
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Icy minicomets caught by a satellite camera?
A geophysicist really risks his or her reputation if he or she suggests that the earth is bombarded each by 20 house-size, icy minicomets. Well, L. Frank, University of Iowa, did just that in 1986. He was duly pilloried for his trouble.
But, at the 1997 spring meeting of the American Geophysical Union, Frank presented new data to back up his previous assertions. The most startling of his new evidence came from a camera aboard a NASA satellite. Time-lapse photos imaged two objects streaking into the atmosphere over Poland and Germany. Frank identified these as clouds of water molecules from disrupted icy minicomets. The clouds had expanded from the house-size minicomets to clouds 3550 miles wide, weighing 20-40 tons.
Frank thinks the minicomets come from a cloud of such objects orbiting the sun from earth out to Jupiter and beyond. Why don't they evaporate in the sunlight and near-vacuum of outer space? Perhaps, thought Frank, they are protected by a thin coating of carbon.
(Roylance, Frank D.; "Space Snowballs Theory Gains Credence," Baltimore Sun, May 29, 1997. Also: Monastersky, R.; "Is Earth Pelted by Space Snowballs?" Science News, 151:332, 1997. Thanks to all who sent in clippings. There are too many to mention here. Frank's photos also appeared on some national news programs.)
Comments. We have already mentioned the minicomets several times in SF. See SF#60/275, for example.
If verified, icy minicomets might well be the source of some of the earth's ocean water. Perhaps they are related to those strange "nebulous" meteors
(SF#86/75) and noctilucent clouds. An intense 40day minicomet "storm" might be useful in accounting for certain historical floods!!