Berkeley-led astronomy team makes rare discovery: A free-floating black hole

A team led by UC Berkeley astronomers has for the first time discovered what they believe to be a free-floating black hole located between 2,280 and 6,260 light years away from Earth.

It’s an incredibly rare discovery, since black holes are invisible. The team of researchers, led by Cal graduate student Casey Lam and astronomy professor Jessica Lu, found the object through gravitational microlensing, in which the brightening of a more distant star is the result of the strong gravitational pull of the object.