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Microbes Rain Down from Space, a Second Scientist Says
By Robert Roy Britt
Senior Science Writer
posted: 09:17 am ET
17 December 2002
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How far up into the sky does the biosphere extend A controversial finding last year of microbes high in Earth's atmosphere and thought to have come from space gained another scientist's support this week. The organisms, collected by a balloon mission to the stratosphere in January 2001, were first studied by Chandra Wickramasinghe of Cardiff University, co-proponent with the late Sir Fred Hoyle of the modern theory of panspermia. The theory states that the Earth was seeded in the past, and is still being seeded, with microorganisms from comets. The experiment gathered microbes as high as 25 miles (41 kilometers). The quantity suggested a ton of them rain down on Earth daily. The critters looked a lot like terrestrial microbes, however, and other scientists have suggested they probably were from Earth and that the experiment was contaminated. Now Milton Wainwright of Sheffield University's Department of Molecular Biology and Biotechnology claims to have isolated a fungus and two bacteria from one of the samples. The results are published in this month's issue of the microbiology journal FEMS Letters. Once again, the organisms are very similar to known terrestrial varieties. There are, however, "notable differences in their detailed properties, possibly pointing to a different origin," according to a press release. Other scientists point out that previously unknown strains of bacteria are routinely discovered on Earth. "Contamination is always a possibility in such studies, but the 'internal logic' of the findings points strongly to the organisms being isolated in space," Wainwright said. "Of course the results would have been more readily accepted and lauded by critics had we isolated novel organisms, or ones with NASA written on them!" Indeed. Panspermia adherents predict the continuing input onto the Earth of fresh organisms that would have untold effects on evolution and might even seed illness. The theory supposes a certain hardiness inherent in space-travelling bacteria. An announcement yesterday of the revival of 2,800-year-old bacteria found buried in Antarctic ice certainly attests to the extreme capabilities of small things. Yet few mainstream scientists have signed on to panspermia. Most leading researchers do acknowledge that life probably could travel between planets, however, embedded inside rocks kicked up by asteroid or comet collisions. No proof exists that life has traveled between planets, though. And no one has formally ruled out panspermia in its purest form, either.
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