Thursday, November 24, 2011

Most liveable alien worlds ranked

Scientists have outlined which moons and planets are most likely to harbour extra-terrestrial life.

Among the most habitable alien worlds were Saturn's moon Titan and the exoplanet Gliese 581g - thought to reside some 20.5 light-years away in the constellation Libra.

The international team devised two rating systems to assess the probability of hosting alien life.

They have published their results in the journal Astrobiology.

In their paper, the authors propose two different indices: an Earth Similarity Index (ESI) and a Planetary Habitability Index (PHI). more