Posted on by Matt Williams

New Research may Explain how Supermassive Black Holes in the Early Universe Grew so Fast

An artist's illustration of a supermassive black hole (SMBH.) The JWST has revealed SMBHs in the early Universe that are much more massive than our scientific models can explain. Could primordial black holes have acted as "seeds" for these massive SMBHs? Image Credit: ESA

Not long ago, the James Webb Space Telescope (JWST) peered into Cosmic Dawn, the cosmological period when the first galaxies formed less than one billion years after the Big Bang. In the process, it discovered something rather surprising. Not only were there more galaxies (and brighter ones, too!) than expected, but these galaxies had supermassive black holes (SMBH) much larger than cosmological models predicted. For astronomers and cosmologists, explaining how these galaxies and their SMBHs (aka. quasars) could have grown so large less than a billion years after the Big Bang has become a major challenge.

Several proposals have been made, ranging from optical illusions to Dark Matter accelerating black hole growth. In a recent study, an international team led by researchers from the National Institute for Astrophysics (INAF) analyzed a sample of 21 quasars, among the most distant ever discovered. The results suggest that the supermassive black holes at the center of these galaxies may have reached their surprising masses through very rapid accretion, providing a plausible explanation for how galaxies and their SMBHs grew and evolved during the early Universe.

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Posted on by Matt Williams

Did Supermassive Black Holes Collapse Directly out of Giant Clouds of gas? It Could Depend on Magnetic Fields

This artist’s impression shows a possible seed for the formation of a supermassive black hole. Credit: NASA/CXC/M. Weiss

Roughly half a century ago, astronomers realized that the powerful radio source coming from the center of our galaxy (Sagittarius A*) was a “monster” black hole. Since then, they have found that supermassive black holes (SMBHs) reside at the center of most massive galaxies. This leads to what is known as Active Galactic Nuclei (AGN) or quasars, where the central region of a galaxy is so energetic that it outshines all of the stars in its galactic disk. In all that time, astronomers have puzzled over how these behemoths (which play a crucial role in galactic evolution) originated.

Astronomers suspect that the seeds that formed SMBHs were created from giant clouds of dust that collapsed without first becoming stars – aka. Direct Collapse Black Holes (DCBHs). However, the role of magnetic fields in the formation of DCBHs has remained unclear since none of the previous studies have been able to simulate the full accretion periods. To investigate this, an international team of astronomers ran a series of 3D cosmological magneto-hydrodynamic (MHD) simulations that accounted for DCBH formation and showed that magnetic fields grow with the accretion disks and stabilize them over time.

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