Gaia mission discovers closest and unique black hole family in Earth's cosmic backyard.
Two black holes, Gaia BH1 and Gaia BH2, have been discovered using data from the European Space Agency's Gaia mission and ground-based telescopes. They are the closest black holes to Earth ever detected, with Gaia BH1 lying just 1,560 light-years away. Both black holes are roughly nine to 10 times more massive than our sun and are completely dark, making them "dormant" or inactive. They were discovered by tracking the movements of two sun-like companion stars orbiting around them. The black holes likely represent a new category of black hole never seen before, with a completely different formation history than x-ray binaries.
