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Hello, the hunt for extraterrestrial life is no longer confined to the pages of

science fiction but occupies astronomers, geologists, mathematicians and new schools of scientists,

astrobiologists and xenobionologists. New planets have been

observed far beyond our solar system and telescopes are being built that will

enable us to look for water and oxygen on these distant planets. If water and oxygen are present, there's every reason

to suppose that some form of life might also exist there. It's even been suggested that

we might find life within our own solar system. One of Jupiter's moon's Europa appears to be covered

in an ice-crusted ocean and there's evidence that water once flowed on Mars.

Under our own planet we've found forms of life, extremophiles, that don't need the sun living in set on energy from volcanic vents on the ocean floor.

This discovery has changed our concept of what life

and what are the chances of ever discovering such a planet?

If we find life, will it be intelligent,

or a simple bacteria like entity?

And if super intelligent aliens exist,

why aren't they here?

With me to discuss the possibility of extraterrestrial life

as Simon Goodwin, a researcher in astronomy at Cardiff University,

and co-author of XTL, Extraterrestrial Life and

How to Find It. Heather Cooper, Space Expert, and Author of Mars, the Inside Story of the Red

Planet, and Ian Stewart, Professor of Mathematics at Warwick University and co-author of the Red Planet, and Ian Stewart, Professor of Mathematics at Warwick University and co-author of the forthcoming

...