What do parasites and black holes have in common? According to astronomers, they both like to drain their host of vital resources. The James Webb Space Telescope recently observed a supermassive black hole starving its own galaxy to death. This black hole leached off so much energy from its host galaxy until it could no longer create new stars, essentially turning it into a giant “dead” mass in the universe.
Astronomers believe most large galaxies have a supermassive black hole at the center. In this case, the galaxy known as GS-10578 or “Pablo’s Galaxy” was the size of the Milky Way in the early universe, about two billion years after the Big Bang. Its total mass is about 200 billion times the Sun’s mass, with most stars made between 11.5 and 12.5 billion years ago. With a mass this large in the early universe, researchers were surprised to see star formation had already halted, suggesting something extraordinary took place.
In a study published in Nature Astronomy, researchers found the central black hole was the cause for the galaxy’s inability to make new stars — an oddity for a galaxy of this size.
“Based on earlier observations, we knew this galaxy was in a quenched state: it’s not forming many stars given its size, and we expect there is a link between the black hole and the end of star formation,” says Dr. Francesco D’Eugenio, a researcher at the Cambridge’s Kavli Institute for Cosmology and a co-lead author of the study, in a media release. “However, until Webb, we haven’t been able to study this galaxy in enough detail to confirm that link, and we haven’t known whether this quenched state is temporary or permanent.”
Galaxies with black holes, like Pablo’s Galaxy, typically contain fast winds of hot gas. These hot gas clouds are thin with little mass. However, the James Webb telescope found a new undetectable wind with earlier telescope models — cold, dense gases that do not release light. These dark gas clouds block the light from their host galaxy.
Webb found the black hole in Pablo’s Galaxy pushing large amounts of wind out of the galaxy at about 1,000 kilometers per second. This quick speed is enough to evade the galaxy’s gravitational pulls. The rate of gas mass being expelled from the galaxy is more than what the galaxy needs to continue creating stars.
“We found the culprit,” D’Eugenio explains. “The black hole is killing this galaxy and keeping it dormant, by cutting off the source of ‘food’ the galaxy needs to form new stars.”
Astronomers have long theorized that black holes can drain a galaxy of its resources, but before the James Webb Space Telescope, it was challenging to observe this effect on early universes.
Another interesting observation the team made was how galaxies act without their stars. Earlier models suggested the ability to create stars would wreck the shape of galaxies. However, the observations from Pablo’s Galaxy suggest this is not always the case as it kept its disc shape, and the stars still in there continue to move in an orderly way.
“We knew that black holes have a massive impact on galaxies, and perhaps it’s common that they stop star formation, but until Webb, we weren’t able to directly confirm this,” says Roberto Maiolino, a professor from the Kavli Institute of Cosmology. “It’s yet another way that Webb is such a giant leap forward in terms of our ability to study the early universe and how it evolved.”
Source: https://studyfinds.org/black-hole-starved-its-galaxy/?nab=0