Could life have arisen on Mars?
- On Saturday, a car-sized rover named Curiosity rocketed off to Mars to seek further clues to that tantalising question — is there life out there?
- Mariner spacecraft that flew past and orbited Earth's neighbour as well as the two Viking landers that touched down on its surface in 1976 sent back images of a cold, bleak, and barren land, with a thin atmosphere that was mostly carbon dioxide and no signs of life.
