New record for "cosmic death"

(NLDO) - Confusing data from the Gaia spacecraft may reveal one of the most sought-after objects in the Milky Way.

Gaia is a small spacecraft of the European Space Agency (ESA), operating as a satellite to explore the sky and map the Milky Way.

According to Science Alert, when looking at a place 5,825 light years away from Earth, Gaia discovered what looked like a dancing red giant star.

An illustration depicting the Gaia spacecraft, the red giant star and the black hole as well as the actual image of it in astronomical data - Photo: Song Wang/ESA

Red giants are dying stars that swell briefly before collapsing. Our Sun will become one in about 5 billion years, possibly swelling big enough to swallow Mercury, Venus, and Earth.

But the signal that Gaia picked up from this new red giant was very different. It seemed to be dancing slowly in orbit with a companion binary star.

However, no companion stars can be observed alongside this red giant star.

Based on the behavior of the red giant star, the research team led by Dr. Song Wang from the Chinese Academy of Sciences determined that the mass of this invisible companion is only 3.6 times the mass of the Sun.

All calculations show it can only be a black hole.

Additionally, its surprisingly wide circular orbit defies current theories of binary evolution and supernova explosions, making it a treasure trove for researchers.

The red giant star-black hole pair, collectively named G3425, may have formed from the second death of a star many times larger than the Sun.

After exploding into a red giant and collapsing for the first time, the star became a very small and massive neutron star. After some time, this neutron star exploded again and collapsed into a black hole.

According to an article published in the journal Nature, this black hole is estimated to weigh about 3.6 times the mass of the Sun.

Previously, the smallest black holes discovered were at least five times as massive as the Sun. So G3425 has set a new record for the smallest black hole that can exist.

The red giant star dancing with the black hole is also very interesting.

The red giant star in G3425 has an estimated mass of about 2.7 Suns, and moves in a relatively wide orbit, taking about 880 days to move around a common center of gravity with the black hole.

Source: https://nld.com.vn/tau-vu-tru-bat-duoc-tin-hieu-la-ky-luc-moi-ve-tu-than-vu-tru-196240922100245329.htm