Super-Eddington black hole LID-568 devours matter at record rate, defying growth theories

Astronomers discovered a supermassive black hole, designated LID-568, that is feeding on matter at an extraordinary rate in the early universe. Observed approximately 1.5 billion years after the Big Bang, LID-568 is growing by devouring material at a speed 40 times higher than the theoretical Eddington limit, challenging existing theories about the evolution of supermassive black holes.

The discovery was made by a cross-institutional team of astronomers led by Hyewon Suh from the International Gemini Observatory/NSF NOIRLab, using the James Webb Space Telescope's (JWST) exceptional infrared observation capabilities. LID-568 was previously identified by the Chandra X-ray Observatory, but observing it was challenging due to its faint appearance from Earth. The light emitted by LID-568 has taken about 1.5 billion years to reach Earth, and although it is faint from our position in the universe, its distance means it must be incredibly bright by itself.

"This black hole is having a feast," said Julia Scharwächter from the Gemini Observatory, highlighting the extreme feeding rate of LID-568. The exceptional feeding rate suggests the possibility of rapid growth of supermassive black holes to their impressive sizes within a relatively short period during the early universe.

The Eddington limit refers to the maximum luminosity a black hole can achieve and the speed at which it can absorb matter, describing the point at which the radiation pressure of the material accreting around a black hole counterbalances its gravitational attraction. Exceeding this limit, as LID-568 does, suggests a phenomenon known as super-Eddington accretion, where a black hole "devours" matter at such a rapid rate that it overcomes the radiation push for brief periods. "A rapid feeding mechanism above the Eddington limit may be one of the possible explanations for why we see these very massive black holes so early in the Universe," said Scharwächter.

To uncover the secrets of LID-568, the team used JWST's NIRSpec integral field spectrograph, which allows obtaining a complete view of the target and the surrounding region, enabling a full-field observation of LID-568 and its environment. Rather than using traditional slit spectroscopy, JWST's instrumentation support scientists suggested that Suh's team use the integral field spectrograph on JWST's NIRSpec. This led to the unexpected discovery of powerful gas flows around LID-568, which act as a release valve for the excess energy generated by extreme accretion.

"Owing to its faint nature, the detection of LID-568 would be impossible without JWST. Using the integral field spectrograph was innovative and necessary for getting our observation," said Emanuele Farina, an astronomer at the International Gemini Observatory/NSF NOIRLab and co-author of the paper appearing in Nature Astronomy.

The observations pointed towards powerful gaseous outflows surrounding LID-568. Further analysis revealed the presence of powerful outflows of material expelled into space by the central black hole, a phenomenon that indicates the super-Eddington accretion phase. The speed and size of these gas flows led the team to infer that a substantial fraction of LID-568's mass growth could have occurred in a single episode of rapid accretion. This suggests that such rapid feeding mechanisms may explain the presence of very massive black holes in the early universe. "The discovery of an Eddington super-accreting black hole suggests that a significant part of mass growth may occur during a single episode of rapid feeding, regardless of whether the black hole originated from a light or heavy seed," said Suh.

Surprisingly, analyses revealed that this black hole is relatively "small" by supermassive black hole standards, with a mass of about 7.2 million times that of the Sun. However, the material in the accretion disk emits a quantity of light enormously greater than what a black hole of this mass should theoretically produce. "Most of the early universe black holes detected by the James Webb are very faint (or undetectable) in X-rays, but LID-568 caught our attention due to its high brightness in X-rays," emphasized Mar Mezcua from the Institute of Space Sciences and the Institute of Space Studies of Catalonia.

Hypotheses about the formation of supermassive black holes include the explosion of extremely massive stars (light seeds) and the direct collapse of enormous gas clouds (heavy seeds). Until now, scientists haven't had concrete evidence to support either theory regarding the formation of supermassive black holes from smaller seeds, and these theories lacked observational confirmation. "This serendipitous result added a new dimension to our understanding of the system and opened up exciting avenues for investigation," said Suh. "Thanks to it, we will be able to improve our understanding of black holes and open interesting avenues of research."

The powerful outflows observed surrounding LID-568 may be acting as a release valve for the excess energy generated by the extreme accretion, helping to regulate its extreme growth and preventing the system from becoming too unstable. This means that some of the material near the black hole is being expelled rather than being completely "devoured."

This discovery provides valuable new insights into the mechanisms of rapidly growing black holes in the early universe, which could contribute to understanding the primitive universe. It opens new research perspectives in the field of astrophysics and could explain how these objects were able to grow so rapidly to become the giants we see today. "This could be a crucial piece to unraveling the puzzle of supermassive black holes in the primordial universe," added Suh.

Sources: energy, Mirage News, DW (Deutsche Welle), Infobae, El Cronista, Pu00e1gina/12, La Opinin, Scienze Notizie

This article was written in collaboration with generative AI company Alchemiq