LONDON, July 22: A huge ball of brightly burning gas drifting througha neighboring galaxy may be the heaviest star ever discovered -- hundreds oftimes more massive than the sun, scientists said after working out itsweight for the first time.Those behind the find say the star, called R136a1, may once have weighed asmuch as 320 solar masses. Astrophysicist Paul Crowther said the obesestar -- twice as heavy as any previously discovered -- has already slimmeddown considerably over its lifetime.In fact, it's burning itself off with such intensity that it shines atnearly 10 million times the luminosity of the sun."Unlike humans, these stars are born heavy and lose weight as they age,"said Crowther, an astrophysicist at the University of Sheffield in northernEngland. "R136a1 is already middle-aged and has undergone an intense weightloss program."Crowther said the giant was identified at the center of a star cluster inthe Tarantula Nebula, a sprawling cloud of gas and dust in the LargeMagellanic Cloud, a galaxy about 165,000 light-years away from our own MilkyWay.The star was the most massive of several giants identified by Crowther andhis team in an article in the Monthly Notices of the Royal AstronomicalSociety.