Astronomers analyzing the brightest supernova ever detected say the titanic flare has reshaped thinking about the death struggle of gigantic stars. Supernova SN2006gy, located 240 million light years away in galaxy NGC 1260, entered the record books in September last year when it dramatically brewed into an explosion 50 billion times brighter than the Sun. It was about 100 times brighter than the flash of a typical supernova, as a dying star is called.
Poring over this extraordinary event, US stargazers said that the SN 2006gy was probably caused by a truly enormous star, a behemoth at least 100 times more massive than the Sun. In addition, they theorize, the star did not blow up just once — but several times. "We usually think of a supernova as the death of a star, but in this case the same star can blow up half a dozen times," said Stan Woosley of the University of California at Santa Cruz, who led the study published in the journal ‘Nature’.
Woosley’s hypothetical model starts with what happens when an exceptionally big star — something 90-130 solar masses — nears the end of its life. The temperature in the stellar core gets so hot that some of the star’s gamma radiation converts into electrons and their anti-matter counterparts, called positrons. The conversion causes the blast of radiation to suddenly fall, and the star begins to shrink. A rival theory suggests that SN 2006ga could not have been created from a single star, but from two very large stars that collided. Indiatimes.