New measurements of the galaxy at the heart of the “Cosmic Horseshoe” indicate that it could house the most massive object ever seen in the universe.

The black hole sits in one of two galaxies that make up the Cosmic Horsehoe, a massive system so large it bends light from a background galaxy into a distinctive horseshoe-shaped Einstein ring. The galaxy is a fossil group,

There are an estimated 40 quintillion (that’s a 4 followed by 19 zeroes) black holes in the universe, but they’re exceedingly hard to find. The defining characteristic of a black hole is that they are invisible.