Astronomers have discovered Gaia-BH3, the largest stellar black hole ever discovered. It has a mass 33 times that of the Sun and is dwarfed only by supermassive black holes and black holes formed by merging with other black holes.
At about 2000 light-years away, Gaia-BH3 is also the second closest black hole to Earth ever discovered. george seabroke Researchers at University College London used the Gaia Space Telescope to discover this stellar black hole, formed from a star that has reached the end of its life.
Because light cannot escape from a black hole, most black holes are discovered by looking for the glow of hot material orbiting around them and falling. However, BH3 is in a dormant state and does not phagocytize substances. Instead, researchers made their discovery by noticing the strange movement of a star that appeared to be orbiting a part of empty space.
The star itself is also unusual, being made almost entirely of hydrogen and helium. Most stars contain at least some heavy elements, which formed in the cores of massive stars and were distributed throughout the universe by supernovae. However, the first generation of stars would have had very low amounts of heavy elements. The composition of BH3's partner star suggests that the massive star that eventually collapsed to form BH3 was also one of these primitive objects and evolved differently from the way massive stars do today. suggests that it is possible. This would explain how black holes became so huge. If it had evolved like a normal star, it would be difficult to explain its size.
The discovery of such a massive black hole was not a complete surprise. Experiments looking for gravitational waves (ripples in space-time caused by the motion of heavy objects) have found signs of them in other galaxies.
“These gravitational wave measurements should lead us to expect that such a black hole exists in our galaxy, but until now it hasn't,” Seabrook said. And this should be just the beginning, he says. “This star is very bright, so if you find a star this bright, you generally expect to find many fainter stars.”
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Source: www.newscientist.com