The exoplanet Gliese 581g, 20 light-years from Earth, is the first confirmed planet in another solar system which lies in its star's habitable zone: the range conducive to liquid water and to life as we know it. Perhaps the most excited scientist on the discovery team is Professor Steven Vogt of the University of California, who went so far as to say, "Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say, my own personal feeling is that the chances of life on this planet are 100 percent."
COMMENT: Wow. I can't go with 100 percent, there are way too many variables. But this is an exciting, memorable discovery. If we can ever determine Gliese 581g does harbor life, this will turn out to be one of the historic moments in the human experience.