Three Earth-sized planets orbiting a star practically next-door might be a good place to hunt for alien life — or at least check out some worlds that are different from anything in our solar system.
The planets orbit a dim, cool star just 39 light-years away in the constellation Aquarius. Each is outside or possibly on the edge of the star’s habitable zone — where average temperatures are just right for liquid water. But there could be niche locales on these worlds where alien life might thrive, Michaël Gillon, an astrophysicist at University of Liège in Belgium, and colleagues report online May 2 in Nature.