The SETI Institute has claimed intelligent alien civilisations could survive on strange "heaven and hell" planets once thought to be totally uninhabitable.

Extraterrestrial hunters have expanded their search for life to include 20,000 red dwarf stars - the dim suns which are thought to create these weird worlds.

Red dwarfs have a much smaller "habitable zone" than our own sun, which means any planet capable of supporting life would have to orbit it at very close proximity.

These planets quickly become "tidally locked" so that one hemisphere constantly faces the star, leaving one side of the world to shiver in constant, freezing darkness whilst the other is scorched by permanent sunlight.

It was thought both sides of these grim planets would be too hostile for life to survive.

But recent research has indicated that a temperate area known as a Goldilocks zone could form between the two faces, allowing intelligent organisms to thrive.

To read more, click here.