Supernova Theory Wrong?
It looks like the previously accepted theory regarding the life cycle of Luminous Blue Variable (LBV) stars is faulty. It had been thought that LBVs needed to first evolve a massive iron core of nuclear fusion ash, lose most of their hydrogen envelope, and only then would they be primed for a core implosion that would trigger a supernova.
However before and after photos of supernova SN 2005gl have shown that pre-explosion it was a LBV that had not lost most of its hydrogen envelope. This places it in the same category of LBV Eta Carinae, which is only 7500 light years from Earth.
From Wikipedia:
Due to the similarity of Eta Carinae and SN 2006jc, Stefan Immler of NASA’s Goddard Space Flight Center suggests that Eta Carinae could explode in our lifetime or even in the next few years. However, Stanford Woosley of the University of California in Santa Cruz disagrees with Immler’s suggestion, and he says it is likely that Eta Carinae is at an earlier stage of evolution and that it has several kinds of material left for nuclear fusion.
