Three panels that show the spiral galaxy before, during, and after the supernova went off near it.
The three panels represent moments before, when and after the faint supernova iPTF14gqr, visible in the middle panel, appeared in the outskirts of a spiral galaxy located 920 million light years away from us. The massive star that died in the supernova left behind a neutron star in a very tight binary system. These dense stellar remnants will ultimately spiral into each other and merge in a spectacular explosion, giving off gravitational and electromagnetic waves. Image credit: SDSS/Caltech/Keck

 

A Caltech-led team of researchers observed the death of a massive star that exploded in a faint and rapidly fading supernova. The gentle death of this massive star suggests that it is part of a binary system and was being robbed of its mass by a dense companion. The event is believed to have resulted in a neutron star orbiting around the original dense and compact companion, suggesting that scientists have witnessed the birth of a neutron star binary system. These dense stellar remnants may ultimately spiral into each other and merge in a spectacular explosion, giving off gravitational and electromagnetic waves.

"What makes these observations so interesting is that such fast and faint explosions have been predicted as the final stage before forming a neutron star binary system, but has never been observed before. It really requires researchers to both find and study the supernova quickly before it fades, which our team was able to do in the case of iPTF14gqr," says Dr. Ragnhild Lunnan, Marie Curie Fellow at the Department of Astronomy and one of the co-authors of the study.

The research was led by graduate student Kishalay De and is described in a paper appearing in the October 12 issue of the journal Science. Several OKC researchers also participated in the study which was based on data from the iPTF survey of which the OKC is a collaborating partner. More information is available here.