- When the Huygens probe lands on Titan later this week,
the pioneering space mission could encounter a bizarre form of life, a
scientist claims.
-
- The European probe will parachute down through the hazy
atmosphere of Saturn's largest moon on Friday after a seven-year voyage.
-
- Now an American team has challenged a basic assumption
that has been used to guide the millions spent on the search for life elsewhere
in the cosmos that life could only exist where there is unfrozen water
and suggested that Huygens could encounter an alien on Titan.
-
- Titan is an environment of yellow clouds and oily black
methane lakes, which is thought to resemble that of Earth billions of years
ago.
-
- The search for water has guided efforts to find life
on Mars, on Jupiter's moon Europa and further afield. Titan is too cold
for large quantities of unfrozen water to exist but Dr Steven Benner, of
the University of Florida, says that life could flourish without water.
-
- In the journal Current Opinion in Chemical Biology, he
and colleagues describe how organisms could survive in exotic environments.
-
- The Florida team identified two absolute requirements
for life to exist a suitable temperature range to allow chemical bonding
and an energy source (for example, the sun or radioactive decay). Titan
meets both requirements.
-
- "This makes inescapable the conclusion that if life
is an intrinsic property of chemical reactivity, life should exist on Titan,"
Dr Benner says.
-
- "Indeed, for life not to exist on Titan, we would
have to argue that life is not an intrinsic property of the reactivity
of carbon-containing molecules under conditions where they are stable."
-
- © Copyright of Telegraph Group Limited 2005.
-
- http://www.telegraph.co.uk
|
