Poor man’s space probe

Press, 15 October 1976, Page 5

Poor man’s space probe

By C. G. McDANIEL, of the Associated Press, through NZPA. Chicago Mr Edward Olsen is going to spend his Christmas holidays in the Antarctic—looking for meteorites and trying to keep warm. Mr Olsen, curator of mineralogy and meteorites at the Field Museum of Natural History, and Mr William Cassidy, a University of Pittsburgh geologist, will leave next month on a scientfiic expedition sponsored by the National Science Foundation.

They have reason to believe that they may be able tc increase the relatively small number of meteorites

known to exist in collections in the world. Japanese expeditions to the Antarctic in the last few years have found about 1000 meteorites. Before these were collected, only about 1900 were in the hands of scientists or institutions —60 per cent of them at the Field Museum.

“It is unlikely,” Mr Olsen said in an interview, “that more meteorites fall on the Antarctic than on other places in the world, but conditions there appear to make their preservation and recovery easier.

“About 70 million meteorites are thought to impact the atmosphere daily. Most of these are tiny, but about

500 of tangible size make it through to the surface of the Earth, and 70 per cent of these fall in the ocean.

“Of the rest, a large percentage fall on unoccupied land areas where they are soon destroyed by the action of rain and freezing, and chemicals in the soil.” The two Americans will use mine-detectors in their search because most meteorites have some metallic content. Most of those found by the Japanese were the size of golf balls, but ranged up to the size of a loaf of bread.

Mr Olsen said that Japanese glaciologists speculate that the meteorites that fall in Antarctica have been tunneled down the 10,000 ft-high elevations by the movement

of the ice over tens of thousands of years and. therefore, concentrated in some areas, such as dry gullies.

Mr Olsen describes the expedition as “a poor man’s space probe.” Before the missions to the Moon, meteorites were the only tangible objects available from space beyond the Earth. “The more sophisticated instruments and techniques developed for the space age make it possible to learn more from meteorites than previously about the early history of the solar system," he said. “Also, it is possible to deduce from them something about the nature of the Earth’s core, which is thought to be similar.”