For the first time, we saw the birth of a black hole or neutron star in a supernova – a liberation

It’s a missing link in astronomy that has just been filled: two independent teams of astronomers have proven that a supernova (the explosion of a massive star at the end of its life) actually produces something very dense with a powerful attraction at its heart.

When the most massive stars in our universe reach the end of their lives, after a few billion years, they hyperinflate and then explode, shedding the outer layers of their atmosphere around them. This sudden and violent event is called a supernova. It causes a flash of light so intense that it can be seen from other galaxies. The bright burst lasts a few days and then fades. But where a star dies, things continue to evolve: the ejected layers of gas form a kind of shell that slowly dissipates into space. And at the heart of this shell, the star’s corpse collapses in on itself to form a dark and ultradense star—sometimes a neutron star, sometimes a black hole.

This is what we have been taught for decades in all astronomy books and courses. This knowledge was made possible by the work of astrophysicists Walter Bade and Fritz Zwicky, who realized in the 1930s that supernovae must mark the transition between a collapsing star and a neutron star. Then we discovered the alternative possibility of forming black holes a little later, when in the 1960s we began to describe these stars as being so dense that even light could not escape.

But all these findings have so far remained theoretical work, based