31.   Other studies have suggested that planet may still have subsurface pools of water, frozen there by the deep cold that now grips the planet.

32.   The planet has valleys, gullies and channels, characteristic marks of the flow of water.

33.   Water is considered essential for the evolution of life and some scientists believe they have evidence, from a Martian rock, that the planet once had life.

34.   The nebula is less than a million years old and its planets have not had time to form from the merging particles.