Behind the odd behavior of a rare type of supernova is a gargantuan star. The supernova, SN2001ig, has been under observation by astronomers because of unexplained changes of its cosmic stripes within weeks. Astronomers have suspected that a star was behind this when a shift from a hydrogen-rich supernova (Type II) to a hydrogen-less variety (Type I) occurred in SN2001ig. Their hunch was confirmed when they were able to see debris from the initial stellar's explosion, and at also when optical observations confirmed that a star was the cause of those unexplained changes.

The supernova, one of only two classified as a transition supernova (Type IIb), sits about 37 million light-years away from Earth in the outer fringe of the galaxy NGC 7424 while the companion star has a yellow-green color and an estimated mass of 10 to 18 times more than that of our Sun.

Astronomers hope that the companion star's presence may help them better define the evolution and aftermath of supernova explosions, and hopefully, link this new knowledge with that of the more powerful supernova relatives, hypernovas which is very important to the world of astronomy. In case you do not know, it has been theorized that the energy released by a hypernova relatively nearby might be capable of causing mass extinctions on Earth. NASA and the University of Kansas released a study in 2005 that suggesting that a mass extinction on Earth 450 million years ago, known as the Ordovician extinction, was triggered by a gamma ray burst which is a result of the hypernova.