Astronomers find ultramassive black hole using gravity and light bending.

Astronomers have discovered an ultramassive black hole, which is 30 billion times the mass of our sun, located at the center of a galaxy in the Abell 1201 galaxy cluster, hundreds of millions of light-years from Earth. The black hole was discovered using gravitational lensing, which magnified the background object, and the Hubble Space Telescope. The black hole is not very active, making it nearly impossible to study by other methods, but gravitational lensing could help detect many more black holes beyond our local universe and reveal how these exotic objects evolved further back in cosmic time.