The image below shows all 786 known planets to scale, as on June 2012. Of most of these planets we don’t know yet whether they are capable of supporting life. According to today’s news, however, new computer models suggest there are many more habitable planets in far-away galaxies than previously thought. Until now, estimates of habitable planets numbers have been based on the likelyhood of them having surface water. But this new model allows scientists to identify planets with underground water kept liquid by planetary heat. That water could also support life.
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Source: Popperfont, BBC