James Webb Space Telescope sees little red dots feeding black holes: 'This is how you solve a universe-breaking problem'

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(JWST).

there may be evidence of rapidly growing, or "accreting," supermassive black holes.

at their hearts.

A sizeable amount of research is being conducted to identify the characteristics of these small red dots and whether their brightness is primarily due to black holes consuming surrounding material.

Gazing at Mars across the universe

When they were first found in 2022, scientists already realized that the JWST's small red specks represented a brand-new kind of galaxy that had never been detected before. They were also puzzled by the fact that these galaxies seemed relatively common in the early universe.

(James Webb Telescope Advanced Deep Extragalactic Survey), the Next Generation Deep Extragalactic Exploratory Public Survey, and the Red Unknowns: Bright Infrared Extragalactic Survey.

A particularly important part of this research into little red dots was data from the RUBIES project, which fittingly covered this topic.

active galactic nucleus (AGN).

Some galaxies appear little red because of a phenomenon called "redshift." As light from a galaxy moves towards us, the universe's expansion stretches its wavelength, also decreasing its frequency.

This shifts the light towards the "red end" of the electromagnetic spectrum. The longer the light travels, the more extreme this redshift effect is, making ancient galaxies be described as "high redshift galaxies."

The most exciting thing for me is the distribution of these extremely red, high-redshift sources," began University of Texas at Austin researcher Steven Finkelstein. "These sources basically disappear at a certain point after the Big Bang," he continued. "If they are in fact actively growing black holes, as we believe is the case about 70% of the time, this suggests the universe experienced an early period of obscured black hole growth.

The existence of cosmology is thanks to feeding of supermassive black holes.

large enough to produce so much light at a time when the 13.8 billion-year-old universe was still just 12% of its current size. This discovery could help solve that mystery.

Supermassive black holes with masses ranging from millions to billions of suns are causing extremely intense brightness in AGNs as a result of the massive turbulence they create in their accretion disks.

Therefore, most of the light coming from these galaxies may be coming from supermassive black hole-powered active galactic nuclei, not stars. This means that the number of stars in small red galaxies does not have to be extremely high to account for their brightness.

"We have finally found the solution to the universe-bending crisis," said Anthony Taylor, a member of our team and a scientist at the University of Texas at Austin.

Not all the questions about the little red dots have been answered. There is one unanswered mystery: why we don't see galaxies like these red dots in our local universe that haven't been significantly redshifted.

One possible explanation could be the "inside-out" growth of galaxies.

People are putting less and less fuel into the area around the supermassive black hole that's at the center of the galaxy. Over time, this means that the black hole is less covered up by dense clouds of gas and dust. As the black hole tosses out surrounding material with powerful beams of hot gas, the galaxy starts to shine more brightly in bluer colors and less in red ones, losing its reddish hue.

which are radiant in X-rays.

This could be due to dense clouds of gas and dust that are good at absorbing X-rays, preventing the release of this high-energy light. Therefore, the absence of X-rays from these red objects could suggest that they are surrounded by a thick layer of black holes.

The team will now pursue a variety of paths to gain a clearer understanding of little red dot galaxies. This will involve studying their sample of galaxies in visible light in the middle of the infrared spectrum.

A closer examination of the small red dots and strategically chosen follow-up observations could potentially unlock the answers to these perplexing ancient galaxies' secrets.

There are always two or more possible ways to explain the puzzling characteristics of a little red dot's behavior," Kocevski said. "This process is an ongoing exchange between our models and observations, finding a balance between what our models match up well with observations and what conflicts with them.

The team's findings were presented at the American Astronomical Society's 245th meeting in National Harbor, Maryland, on January 15th, and were accepted for publication in The Astrophysical Journal.