'1-in-10-billion' star system is doomed to explode in a fiery kilonova

 

'1-in-10-billion' star system is doomed to explode in a fiery kilonova

An illustration of a rare binary star system consisting of a massive star and a dead neutron star orbiting one another

For the first time, scientists have discovered a double-star system that is doomed to explode in a fiery "kilonova," a precious-metal-creating blast caused by the merger of two stellar corpses.

The kilonova — which will send gold, silver, platinum and other new heavy elements careening into space — won't happen for millions of years. But the precursor system that is set up for this massive merger is a rare sight nonetheless, consisting of one massive star and a dense, dead neutron star locked in a shared orbit. Astronomers estimate that there are fewer than 10 such systems in our galaxy.

"We know that the Milky Way contains at least 100 billion stars and likely hundreds of billions more," André-Nicolas Chené, an astronomer at the National Science Foundation's NOIRLab, said in a statement. "This remarkable binary system is essentially a one-in-ten-billion system. Prior to our study, the estimate was that only one or two such systems should exist in a spiral galaxy like the Milky Way."

Kilonovas are huge flashes of electromagnetic radiation released during the merger of either two neutron stars — the collapsed cores of massive stars that ran out of fuel — or a neutron star and a black hole.