Beyond Earth, what's the most likely site of life?

15th March 2010
Beyond Earth, what's the most likely site of life? (iStock)

Asked by: Mark Pitkin, London

That depends on what you mean by life. If you mean life as we know it, the best bet is Mars, as it’s the most Earth-like of the other planets. But even the Earth is home to so-called extremophiles – organisms that can cope with extraordinary temperatures or radiation – so we shouldn’t be surprised if life exists elsewhere in the Solar System.