Hundreds of stars mysteriously disappeared from the sky

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Stars do not disappear from the sky without leaving a trace. The so-called ordinary star will gradually lose the helium it is composed of before it extinguishes, dies and then becomes a white dwarf. A massive star's life would end in a supernova explosion: its core would then suddenly contract and expel the rest of the star into space, before forming a black hole. Two processes are known and identified by astronomers.

However, hundreds of stars suddenly disappeared. According to scientistsAlthough these stars are included in astronomical surveys, they are absent from the new stars. According to an international team led by astrophysicist Alejandro Vigna Gomez of the Niels Bohr Institute in Denmark and the Max Planck Institute for Astrophysics in Germany, some massive stars do die in supernova explosions before forming stars.

“The collapse was so complete that no explosions occurred, nothing escaped, and no bright supernovae appeared in the night sky.” The astrophysicist explains. When a massive star dies, its mass is ejected into the surrounding space and a cloud of dust and gas is formed that remains for hundreds of thousands or even millions of years. During this time, its core collapses under gravity and sometimes forms a black hole. Mounting evidence suggests that massive stars could collapse directly into these black holes, without going through a supernova. A process that leaves no visible residue behind which would explain the sudden disappearance of the star.

Extraterrestrial thesis

To understand this phenomenon, researchers launched in 2019 Vasco project, of sources vanishing and reappearing over a century of observations. Based on ancient data, scientists are analyzing these hidden stars to identify them and estimate their number. The goal is also to verify that these are not registry errors. Currently, there are more than 800 missing stars according to censuses made since the 1950s, and in addition to the formation of black holes, researchers have put forward the theory of extraterrestrial intelligence.

Astronomers from the Search for Extraterrestrial Intelligence (SETI) program are also participating in the Vasco project. These researchers hypothesized that advanced extraterrestrial civilizations may have developed technologies capable of changing the appearance of a star. A thesis that borders on science fiction and is currently not favored by experts.