Astronomers have discovered one of the largest black holes ever found — an ultramassive monster roughly 30 billion times the mass of the sun — using a space-time trick predicted by Albert Einstein.
The colossal black hole, which lurks 2.7 billion light-years from Earth in the brightest galaxy of the galaxy cluster Abell 1201, was given away by a giant arc of warped light from a background galaxy that had been stretched and smudged by the black hole's immense gravitational field.
