SETI spends enormous amounts of money
and resources looking for life outside of Earth's realm, but life forms
so alien that scientists may simply not have recognized evidence of
their existence could inhabit the Earth, according to a leading
scientist.
Dr Tom Gold, emeritus professor of astronomy at Cornell University in
America, believes that organisms based on silicon - completely
unrelated to all the carbon-based life man has encountered so far - may
live at great depths.
In a forthcoming book he will suggest that scientists should take the
possibility more seriously. Gold, who is a member of the Royal Society,
previously predicted that vast amounts of more conventional bacteria
live miles down within the Earth's crust. Scientists initially
dismissed the idea, but many now agree with him.
![Silicon Lifeform]()
"So
long as nobody suspects there could be silicon-based life, we may just
not be clever enough to identify it," he said last week.
Rocks bearing signs of silicon-based organisms may already be sitting
in laboratories, he believes, with their significance overlooked.
Every known living organism, from bacteria to mankind, is based on the
chemistry of carbon, which forms the complex molecules such as DNA that
are central to our existence. Scientists believe that if
extraterrestrial life is found, the chances are that it, too, will be
carbon-based.
