What is Gaia-BH3?

About Gaia-BH3

• It is the most massive stellar black hole yet discovered in the Milky Way galaxy.
• This black hole was spotted in data from the European Space Agency’s Gaia mission because it imposes an odd ‘wobbling’ motion on the companion star orbiting it. 
  • The researchers used the European Southern Observatory’s Very Large Telescope in Chile’s Atacama Desert and other ground-based observatories to confirm the mass of Gaia BH3.
• It has a mass that is nearly 33 times that ofoursun, and it’s located 1,926 light-years away in the Aquila constellation, making it the second-closest known black holeto Earth.
  • The closest black hole is Gaia BH1, which is located about 1,500 light-years away and has a mass that is nearly 10 times that of our sun.
• Most Massive Black Hole in Milky Way galaxy: The title for the most massive black hole in our galaxy will always belong to Sagittarius A*, the supermassive black hole located at the center of the Milky Way, which has about 4 million times the mass of the sun, but that is because it’s a supermassive black hole, rather than a stellar black hole.

Stellar black hole vs Supermassive black hole

• Stellar-mass black holes are formed from the gravitational collapse of a single staror from the merger of two neutron stars.
• Therefore, stellar-mass black holes have masses similar to the masses of stars.
• More specifically, stellar-mass black holes have masses ranging from about 3 times the mass of our sun to about 50 times the mass of our sun.
• In contrast, supermassive black holes have a mass greaterthan about 50,000 times the massof our sun and are typically millions to billions of times the mass of our sun.
• Supermassive black holes are far too large to have formed from the gravitational collapse of a single star.
• However, scientists do not currently know how supermassive black holes form.
• Supermassive black holes are always found at the center of a galaxy and almost all galaxies have a supermassive black hole at its center. 

This seems to suggest that each supermassive black hole is formed as part of the formation of its galaxy.

Q1: What is a Black hole?

A black hole is a region in space where gravity pulls so much that even light can not get out. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying. Because no light can get out, it is difficult to detect a black hole. The largest black holes are called "supermassive." These black holes have masses that are more than 1 million suns together. Albert Einstein first predicted the existence of black holes in 1916, with his general theory of relativity.

Source: Astronomers spot a massive ‘sleeping giant’ black hole less than 2,000 light-years from Earth