Last month, Courtney Dressing and David Charbonneau of the Harvard-Smithsonian Centre for Astrophysics in Cambridge, Massachusetts, announced that the nearest neighbouring Earth-like planet is probably orbiting a small, cool red dwarf star about 13 light years away.
Dressing and Charbonneau sifted through data from the planet-hunting Kepler space telescope. Kepler looks for dips in starlight as planets pass in front of their host stars, as seen from Earth. The pair found 95 dim red dwarfs that host possible planets. That included three Earth-sized worlds in the habitable zone – the region around a star in which temperatures would allow liquid water to exist.