Most Massive Star Ever Weighs In

The most massive star yet discovered has been "weighed," astronomers say, and it tips the scales at a whopping 114 times the mass of the sun. The enormous star forms the bigger half of a rapidly orbiting binary system and it far outstrips both its companion star and the previous record holder—which weigh in at 84 and 83 solar masses, respectively.

The star, which is 20,000 light years from Earth and known unpoetically as A1, was measured by comparing its orbit to Hubble data. Astronomers surmise that stars can't get much bigger than 150 solar masses without becoming unstable. (More space stories.)