The Kepler space telescope has reached a milestone, with the number of discovered alien planets surpassing 1,000! Pushing the total over a thousand, was today's announcement of eight new exoplanets, all of which appear to be in the "habitable zone." One of them, Kepler-438b, 470 light-years away, is just 12% wider than Earth, and is likely to be a rocky world. More on the milestone here.
Pictured: Artist's illustration of Kepler-22b