Astronomers may have witnessed the birth of a black hole


Astronomers are increasingly drawing back the curtains on black holes. In the past few years, we have finally captured actual photos of these fearsome creatures and measured the gravitational waves – ripples in spacetime – that they create when colliding. But there’s still a lot we don’t know about black holes. One of the biggest enigmas is exactly how they form in the first place.

My colleagues and I now believe we have observed this process, providing some of the best indications yet of exactly what happens when a black hole forms. Our results are published in two papers in Nature and the Astrophysical Journal.

Astronomers believe, on both observational and theoretical grounds, that most black holes form when the center of a massive star collapses at the end of its life. The star’s core normally provides pressure, or support, using heat from intense nuclear reactions. But once such a star’s fuel is exhausted and nuclear reactions stop, the inner layers of the star collapse inward under gravity, crushing down to extraordinary densities.