This makes it the fastest-growing black hole we know of in the entire Universe; its enormity tips it into the category of ultramassive black holes.

At time of discovery, astronomers estimated the black hole's mass at around 20 billion solar masses, putting it in the category of ultramassive (over 10 billion solar masses), and its accretion rate - how much material it devours - at half a solar mass a day.

An ultramassive black hole clocking in at around 40 billion solar masses is at the heart of the galaxy Holm 15A, around 700 million light-years away.

And then there's the ultramassive black hole powering the quasar TON 618 - an absolute beast at 66 billion solar masses.

"It's the biggest black hole that's been weighed in this early period of the Universe," Onken said.

Recent studies, however, have revealed that quasars hosting supermassive black holes didn't just exist in the early Universe - they seem to have been quite common.