Our nearest galactic neighbor Alpha Centauri has a planet!
October 17, 2012
Very exciting news in the world of planet hunting! Our nearest star (that’s not our own sun) Alpha Centauri has an Earth-mass planet orbiting it! The planet is 1.13 times the mass of Earth, but only takes 3.24 days to orbit the star. That short orbital period means it’s VERY close to its parent star Alpha Centauri B, and probably has a surface covered in hot molten lava- not a pleasant place. The Alpha Centauri system is famous because it’s so close to us and has been included in many sci fi movies and stories. It’s a triple-star system only 4.3 light years away, and if it does turn out to have a habitable planet, it would no doubt be the destination of our first interstellar travels, if and when we ever develop the technology for it. This planet was found using the radial velocity method, which observes the faint wobble that an orbiting planet exerts on its parent star. Apparently this wobble was so faint and hard to detect that its discovery is somewhat of a milestone in the art of planet hunting. Scientists also think that this discovery increases the chance that we will find a habitable world in the Alpha Centauri system. For more info check out Bad Astronomy or New Scientist.