Massive Blue Supergiant Challenges Theory of How Big a Star Can Be

Welcome to the Tarantula Nebula, home to heavy-weight stars. Using data from the Hubble Space Telescope and Very Large Telescope in Chile, scientists have found a star estimated at about 265 times the mass of the sun. That makes it by far the most massive star ever found, and challenges astronomers' notions of just how big a star can get. The Tarantula Nebula is 165,000 light years away in the the Large Magellenic Cloud galaxy. This star, called R136a1, is located in the R136 stellar cluster; with 10 million times the luminosity of the sun, it's the brightest of a bevy of massive stars recently discovered. The finding, published earlier this month in the Monthly Notices of the Royal Astronomical Society, may require scientists to come up with a new stellar life cycle for the most massive stars. The life a star leads depends on its mass, and the previously estimated mass limit was thought to be around 150 times the sun's mass. Lead author Paul Crowther explains that the big guy falls into the stellar category of "blue supergiants," which are still a mystery from start to finish: It's not clear whether a star can be born this big, or whether it grows through mergers.