U.S. astronomers discover the fastest-feeding black hole in the early Universe

Supermassive black holes exist at the center of most galaxies, and modern telescopes continue to observe them at surprisingly early times in the Universe’s evolution.

It’s difficult to understand how these black holes were able to grow so big so rapidly. But with the discovery of a low-mass supermassive black hole feasting on material at an extreme rate, seen just 1.5 billion years after the Big Bang, astronomers now have new insights into the mechanisms of rapidly growing black holes in the early Universe.

LID-568 was discovered by a cross-institutional team of astronomers led by International Gemini Observatory and National Science Foundation NOIRLab astronomer Hyewon Suh.

They used the James Webb Space Telescope to observe a sample of galaxies from the Chandra X-ray Observatory’s COSMOS legacy survey.

In a stunning discovery, Suh and her team found that LID-568 appears to be feeding on matter at a rate 40 times its Eddington limit. This limit relates to the maximum luminosity that a black hole can achieve, as well as how fast it can absorb matter, such that its inward gravitational force and outward pressure generated from the heat of the compressed, infalling matter remain in balance.

“This black hole is having a feast,” said International Gemini Observatory and National Science Foundation NOIRLab astronomer Julia Scharwächter, co-author of a new paper published in Nature Astronomy.

These results provide new insights into the formation of supermassive black holes from smaller black hole ‘seeds’, which current theories suggest arise either from the death of the Universe’s first stars (light seeds) or the direct collapse of gas clouds (heavy seeds). Until now, these theories lacked observational confirmation.

The discovery of LID-568 also shows that it’s possible for a black hole to exceed its Eddington limit, and provides the first opportunity for astronomers to study how this happens. It’s possible that the powerful outflows observed in LID-568 may be acting as a release valve for the excess energy generated by the extreme accretion, preventing the system from becoming too unstable.