Analyzing images from the James Webb Space Telescope (JWST), a team of astronomers led by Dr. Lukas Furtak and Prof. Adi Zitrin from Ben-Gurion University of the Negev has made a groundbreaking discovery: an extremely red, gravitationally lensed supermassive black hole lurking in the depths of the early universe. This mysterious celestial entity, shrouded in a veil of dust, challenges existing theories about the growth and evolution of galaxies and their central black holes.
Published in Nature, their findings shed light on a cosmic enigma that has intrigued scientists for decades. The JWST, launched just two years ago, has already revolutionized our understanding of early galaxy formation, revealing a plethora of previously unseen phenomena and objects.
The astronomers stumbled upon their discovery while poring over images taken for the UNCOVER program, which focused on the galaxy cluster Abell 2744. Within these images, they identified three compact, red objects that defied conventional explanations. Further analysis revealed that these enigmatic dots were multiple images of the same distant source, appearing as they did when the universe was a mere 700 million years old.
Utilizing sophisticated numerical models and spectroscopic data from the JWST/NIRSpec instrument, the researchers confirmed their suspicions: the red dots were, in fact, a supermassive black hole accreting matter at an astonishing rate. The unprecedented depth of the obtained spectrum provided invaluable insights into the black hole's properties, including its mass and redshift.
However, the most startling revelation came when comparing the black hole's mass to that of its host galaxy. Despite its diminutive size, the black hole exhibited a mass far exceeding what current models predict, challenging existing paradigms of black hole-galaxy coevolution.
According to Prof. Jenny Greene from Princeton University, co-lead author of the study, "All the light of that galaxy must fit within a tiny region the size of a present-day star cluster. The gravitational lensing magnification of the source gave us exquisite limits on the size. Even packing all the possible stars into such a small region, the black hole ends up being at least 1% of the total mass of the system."
This unexpected discrepancy raises profound questions about the origins and growth mechanisms of supermassive black holes in the early universe. Prof. Zitrin remarks, "We do not currently know which came first—the galaxy or black hole, how massive the first black holes were, and how they grew."
Journal Information: Lukas J. Furtak et al, A high black hole to host mass ratio in a lensed AGN in the early Universe, Nature (2024). DOI: 10.1038/s41586-024-07184-8