2024-01-14 18:18:42
Space
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The “Freedom of the Stars” fileIt is a missing link in astronomy that has just been filled: two independent teams of astrophysicists prove that a supernova (the explosion of a massive star at the end of its life) does indeed produce at its heart a very dense star, with powerful attraction.
When the most massive stars in our universe reach the end of their lives, after a few billion years, they swell excessively then explode, shedding the outer layers of their atmosphere around them. This sudden and violent phenomenon 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 then fades. But where the star died, things continue to evolve: the expelled layers of gas form a kind of shell that slowly disperses into space. And at the heart of this shell, the corpse of the star compresses on itself to form a dark and ultradense star – sometimes a neutron starand sometimes a black hole.
This is what we have learned in all astronomy books and courses for decades. This knowledge was made possible by the work of astrophysicists Walter Baade and Fritz Zwicky, who understood in the 1930s that supernovae must mark the transition between a star which collapses on itself and a neutron star. Then we discovered a little later the alternative possibility of a black hole forming, when in the 1960s we began to describe these stars so dense that even light cannot escape.
But all these conclusions remained theoretical work until now, relying
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