Astronomers have found potentially the largest black hole yet discovered. The black hole weighs around 30 billion times more than the sun and is located hundreds of millions of light-years from Earth, in the center of a galaxy. It’s known as an “ultramassive” black hole, which is bigger than the usual “supermassive” black holes that weigh anywhere between a few million to a few billion solar masses.
The astronomers discovered the black hole when observing a galaxy further away than the one containing the black hole. They used the gravity of a closer galaxy to magnify the background object, in what’s called gravitational lensing. This effect is caused by the gravity of extremely massive objects bending light around them. This makes distant objects more visible to telescopes.
The black hole is located in one of the galaxies of the Abell 1201 galaxy cluster. It’s not very active, meaning it’s not swallowing too much material and therefore not producing strong X-ray radiation. Such black holes are nearly impossible to study by other methods. However, gravitational lensing makes it possible to study inactive black holes, something not currently possible in distant galaxies. This approach could let us detect many more black holes beyond our local universe and reveal how these exotic objects evolved further back in cosmic time.
