Gaia BH3 has a mass nearly 33 times the Sun’s and is the heaviest black hole of stellar origin found so far in the Milky Way. It lies 1,926 light-years away in the constellation Aquila. ESA announced the find in April 2024.
Astronomers spotted it from the wobble of a companion star, an ancient giant that formed in the first two billion years after the Big Bang. The black hole is dormant, so it gives off no X-rays and cannot be seen directly. The previous record holder in our galaxy, Cygnus X-1, has about 20 solar masses, and the average known stellar black hole has about 10. The companion has few elements heavier than hydrogen and helium, which supports the idea that such stars can collapse into especially heavy black holes.
~33 solar masses
Mass of Gaia BH3