Astronomers Spot Early Universe’s Fastest-Feeding Black Hole

Named LID-568, this 7.2-million-solar-mass black hole appears to be feeding on matter at a rate 40 times its Eddington limit and is seen as it existed just 1.5 billion years after the Big Bang.

Eddington 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.

LID-568 appears to be feeding on matter at a rate 40 times its Eddington limit.

This accreting black hole was detected by the NASA/ESA/CSA James Webb Space Telescope in a sample of galaxies from Chandra’s COSMOS legacy survey.

This population of galaxies is very bright in the X-ray part of the spectrum, but are invisible in the optical and near-infrared.

Webb’s unique infrared sensitivity allows it to detect these faint counterpart emissions.

LID-568 stood out within the sample for its intense X-ray emission, but its exact position could not be determined from the X-ray observations alone.

So, rather than using traditional slit spectroscopy, Webb’s instrumentation support scientists suggested that the study authors use the integral field spectrograph on Webb’s NIRSpec (Near-Infrared Spectrograph) instrument.

“Owing to its faint nature, the detection of LID-568 would be impossible without Webb,” said Dr. Emanuele Farina, an astronomer at the International Gemini Observatory and NSF’s NOIRLab.

“Using the integral field spectrograph was innovative and necessary for getting our observation.”

“This black hole is having a feast,” said Dr. Julia Scharwächter, also from the International Gemini Observatory and NSF’s NOIRLab.

“This extreme case shows that a fast-feeding mechanism above the Eddington limit is one of the possible explanations for why we see these very heavy black holes so early in the Universe.”

These results provide new insights into the formation of supermassive black holes from smaller black hole ‘seeds.’ Until now, theories lacked observational confirmation.

“The discovery of a super-Eddington accreting black hole suggests that a significant portion of mass growth can occur during a single episode of rapid feeding, regardless of whether the black hole originated from a light or heavy seed,” said Dr. Hyewon Suh, also from the International Gemini Observatory and NSF’s NOIRLab.

“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,” the astronomers said.

“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.”

“To further investigate the mechanisms at play, the team is planning follow-up observations with Webb.”

Their results appear today in the journal Nature Astronomy.

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H. Suh et al. A super-Eddington-accreting black hole ~1.5 Gyr after the Big Bang observed with JWST. Nat Astron, published online November 4, 2024; doi: 10.1038/s41550-024-02402-9

This article is based on a press-release provided by NSF’s NOIRLab.