New studies cast doubt on Martian life theory
December 22, 1996
Web posted at: 2:00 p.m. EST=20
NEW YORK (CNN) -- Independent tests have cast doubt over earlier studies =
that detected possible signs of past life on a Martian meteorite, =
according to an article in Sunday's New York Times.=20
Results of one study appeared to invalidate three of four lines of =
evidence scientists said in August were signs of microorganisms, and =
another study raised doubts about the fourth line of evidence.=20
....
Scientists who worked on the latest studies were almost apologetic about =
their findings, and stressed that their findings did not conclusively =
rule out the possibility of life on Mars.=20
The new studies indicated that some of the signs taken to indicate =
possible life could have come from contaminates on the Antarctic ice.=20
"There is nothing else in this rock that looks like nanofossils, and the =
things that look like nanofossils aren't," said Dr. Harry McSween Jr. of =
the University of Tennessee at Knoxville.=20
McKay said that his team disagreed with the new interpretation.=20
"We're basically not worried by all this," he said. "For one reason, we =
don't think they're looking at the same places in the meteorite."=20
....
The report of the new studies -- by McSween, Dr. Ralph Harvey of Case =
Western Reserve University in Cleveland and Dr. John Bradley, a =
geochemist and executive director of MVA Inc., a company in Norcross, =
Georgia, that specializes in the microscopic analysis of materials -- =
appeared in Geochimica et Cosmochimica Acta, an international journal of =
geochemistry.