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The Webb Space Telescope discovers quasars where they shouldn't exist

Astronomers have used the Web to discover individual ancient quasars of uncertain origin

This image taken by Webb shows an ancient quasar (in the red circle) with fewer neighboring galaxies than expected. Credit: Christina Eilers/EIGER team
This image taken by Webb shows an ancient quasar (in the red circle) with fewer neighboring galaxies than expected. Credit: Christina Eilers/EIGER team

A quasar is a very bright region at the center of a galaxy, powered by a supermassive black hole. As this black hole pulls in gas and dust from its surroundings, it releases an enormous amount of energy, making the quasar one of the brightest objects in the universe. Quasars have been discovered that formed only a few hundred million years after the Big Bang, and the question arises as to how they could become so massive and bright in such a short cosmic time.

Astronomers used the Webb Space Telescope to peer back in time, more than 13 billion years, to study the environments of five known ancient quasars. They found surprising diversity in their environments, or "quasar fields". Some quasars reside in very dense fields with more than fifty neighboring galaxies, as all models predict, but the remaining quasars seem to be drifting in the void, with only a few stray galaxies in their vicinity.

These isolated quasars challenge scientists' understanding of how such luminous objects could have formed so early in the universe, without a significant source of surrounding matter to feed their black hole development.

A quasar is the very bright center of distant galaxies. Credit: NASA, ESA, CSA, Joseph Olmsted (STScI)
A quasar is the very bright center of distant galaxies. Credit: NASA, ESA, CSA, Joseph Olmsted (STScI)

"Contrary to previous opinion, we find that on average these quasars are not necessarily in these very dense regions of the early universe. Some of them seem to be in the middle of nowhere," says Anna-Christina Eilers from MIT. "It's hard to explain how these quasars got so big if there doesn't seem to be a source feeding them."

There is a possibility that these quasars may not be as lonely as they seem, but surrounded by galaxies that are heavily shrouded in dust and therefore hidden from view. Eilers and her colleagues hope to direct their observations and try to see through the cosmic dust, to understand how quasars got so big so quickly in the early universe.

The five recently observed quasars are among the oldest observed to date, more than 13 billion years old. They are thought to have formed 600 to 700 million years after the Big Bang. The mass of the supermassive black holes that drive the quasars is a billion times the mass of the Sun, and they are a trillion times brighter. Because of their very high luminous intensity, the light from each quasar can travel beyond the age of the universe, far enough to reach today's highly sensitive Webb detectors.

"It's simply amazing that we now have a telescope that can capture light from 13 billion years ago in such detail," says Eilers. "For the first time, Webb allowed us to look at the environment of these quasars, where they developed, and what it was like."

The team analyzed images of the five oldest quasars that Webb took between August 2022 and June 2023. The observations of each quasar consisted of multiple "mosaic" images, or partial views of the quasar field, which the team stitched together to create a complete picture of each quasar's surroundings.

for the scientific article

More of the topic in Hayadan:

Comments

  1. I think the theoretical solution at least has been found: in fact the ancient black holes that appeared after the big bang were created even before the appearance of the first star. Until now it was known that black holes can form in two forms, one is a giant star collapsing in on itself, or in the merger of two black holes creating a supermassive black hole with a mass of up to a billion times the mass of the Sun. However, advanced simulations indicated a deviation between the model and the observation. The massive black holes were up to ten times heavier than they would have been if they had merged and swallowed all the dust and gas around them.
    Therefore, it is assumed that these quasars were formed from a dense and boiling plasma that was created at the beginning of the Big Bang and collapsed in on itself until it became a black hole.

  2. I think the theoretical solution at least has been found: in fact the ancient black holes that appeared after the big bang were created even before the appearance of the first star. Until now it was known that black holes can form in two forms, one is a giant star collapsing in on itself, or in the merger of two black holes creating a supermassive black hole with a mass of up to a billion times the mass of the Sun. However, advanced simulations indicated a deviation between the model and the observation. The massive black holes were up to ten times heavier than they would have been if they had merged and swallowed all the dust and gas around them.
    Therefore, the assumption is that these quasars were created from a boiling plasma that was created at the beginning of the big bang and collapsed in on itself...

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