A type of supernova that can completely annihilate the star without leaving any traces was discovered by a group of researchers who used data from the European Space Agency’s Gaia satellite.
They studied a supernova, first discovered 14 November 2016 and called SN 2016iet. They first discovered that the star that caused the explosion lived in an isolated region, a region where few stars formed. As evidence of this, there was the weak emission of hydrogen coming from the same supernova position — an unusual thing for such a massive star.
They then discovered other strange characteristics: the long duration of the explosion, the great energy emitted and the unusual chemical traces emitted by the explosion relatively poor of heavier elements, things for which there are no similar sightings in the astronomical literature. In the study, published in the Astrophysical Journal, other features of the star that exploded and gave birth to the supernova are described.
It had 200 times the mass of our Sun. These are very large and massive stars that live little (life can be estimated in millions of years) and that usually die emitting large amounts of heavy metals into the surrounding space. The core, however, collapses and becomes a neutron star or black hole.
In these supernovae, the core that collapses produces large amounts of gamma rays. This, in turn, causes a large production of particle pairs and antiparticles on the run, and this leads to a catastrophic thermonuclear explosion that practically annihilates the entire star, including the nucleus.
The theory concerning supernovae with couple instability predicted that these explosions could only occur in environments that were poor in metal, such as dwarf galaxies or the primordial universe. And this discovery confirms it: the supernova SN 2016iet has, in fact, occurred in a metal-dwarf galaxy at a billion light-years away from us.
“This is the first supernova in which the mass and metal content of the exploding star falls within the range predicted by theoretical models,” reports Sebastian Gomez, a researcher at the Center for Astrophysics and one of the authors of the study.