The explosion is a supernova, occurred when the star's sister reached the end of its life

Sep 10, 2014 20:57 GMT  ·  By

Data obtained with the help of NASA's Hubble Space Telescope indicates that, about 11 million light-years from us, in the galaxy M81, a star is holding on for dear life at the core of a massive cosmic explosion.

In the image accompanying this article, which is an artist's impression of the anatomy of this unfolding space drama, the star is the teeny tiny dot at the center of the colorful sphere, which represents debris birthed by the explosion.

How it all began

Astronomers with the Space Telescope Science Institute in the US say that the star at the center of this massive explosion used to be part and parcel of a binary system, i.e. two celestial bodies that sit very close to one another and that orbit a common center of mass.

In time, the remaining star's companion siphoned most of its hydrogen envelope to its baby sister. Eventually, it reached the end of its life and self-destructed in a massive stellar explosion known as a Type IIb supernova.

“This is like a crime scene, and we finally identified the robber. The companion star stole a bunch of hydrogen before the primary star exploded,” says space enthusiast Alex Filippenko, a Professor of Astronomy at the University of California, Berkeley.

Its sister might be long gone, but the other star that formed this binary system is still very much alive. Granted, it’s surrounded by the remains of its extinct companion and not all that easy to spot because of the glow of the supernova, but it is still holding on.

Finding the secluded star

As detailed by the astronomers behind this research project, light originating from the supernova hiding this star was first detected in 1993. At that time, scientists named the stellar explosion SN 1993J. Based on the particularities of this supernova, they concluded that it had occurred in a binary system.

Hence, they set out to look for the dead star's companion. However, it took astronomers about two decades to succeed in pinning down the location of the remaining star among the debris and the glare of the explosion hiding it from sight.

The Hubble Space Telescope helped scientists find this star by identifying and mapping the ultraviolet light originating from it. “We were able to get that UV spectrum with Hubble. This conclusively shows that we have an excess of continuum emission in the UV, even after the light from other stars has been subtracted,” explains researcher Azalee Bostroem.