Paul Sutherland in Scientific American:
David McKay, chief of astrobiology at NASA's Johnson Space Centre in Houston, says powerful new microscopes and other instruments will establish whether features in martian meteorites are alien fossils.
He says evidence for life in the space rocks could have been claimed by the UK if British scientists had used readily-available electron microscopes. Instead, images of colonies of martian bacteria were collected by American scientists.
The NASA team is already convinced that colonies of micro-organisms are visible inside three martian rocks that landed on Earth. If so, this would have profound implications for our understanding of life in the universe.
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