Astronomers have made a groundbreaking discovery, identifying what they describe as the “most massive” black hole in the Milky Way yet. This black hole is at least 33 times larger than the Sun and is situated approximately 2,000 light years away from Earth.
The discovery was made by astronomers at the European Southern Observatory’s Gaia mission, who noticed a star exhibiting a wobbling motion as it orbited the area.
Named Gaia BH3, this black hole is the second closest to Earth and is located in the Aquila constellation. The word “Gaia” is of Latin origin, meaning “the eagle.”
“No one was expecting to find a high-mass black hole lurking nearby, undetected so far,” said Pasquale Panuzzo, an astronomer from the National Centre for Scientific Research at the Observatoire de Paris. “This is the kind of discovery you make once in your research life,” the astronomer added.
The star that collapsed to form the Gaia BH3 black hole was likely a metal-poor star
When stars reach the end of their lives, they can form black holes. While most stars expand, lose mass, and cool down to become “white dwarfs,” some stars, known as “metal-poor stars,” lose less mass and do not contain heavy elements. Instead of becoming white dwarfs, these stars collapse in on themselves, forming black holes.
This suggests that the star that collapsed to form the Gaia BH3 black hole was likely a metal-poor star. Further clues can be gathered from the “wobbly” star orbiting the black hole, as stars in pairs tend to have similar properties. Intriguingly, the wobbly star is also a metal-poor star.
NASA scientists believe that there are more than 50 stellar black holes in the Milky Way galaxy. In a separate discovery earlier in January, astronomers announced the finding of the oldest black hole ever discovered, dating back to the early universe over 13 billion years ago. This black hole is located in an ancient galaxy known as GN-z11, which is located 13.4 billion light-years away. The discovery was made using the James Webb Space Telescope.