The blockbuster film Avatar featured a planet imagined to be circling Alpha Centauri B, the star closest to our sun. Now astronomers have discovered there really might be a system of planets there. The new planet orbiting Alpha Centuri B is so close to the star that it would not be habitable to life as we know it. But there could be other planets. Greg Laughlin is Chair of the Department of Astronomy and Astrophysics at the University of California Santa Cruz and a blogger at oklo.org.