James Webb Space Telescope confirms that Pablo’s Galaxy is unable to form new stars and is doomed.

Using the NASA/ESA James Webb Space Telescope, an international team of astronomers has confirmed that supermassive black holes can effectively "starve" their host galaxies, preventing them from forming new stars.

The team including researchers from the United Kingdom, Spain, the United States, Canada, Italy and Germany made this discovery by observing a galaxy approximately the size of the Milky Way, existing two billion years after the Big Bang. Like many large galaxies, it hosts a supermassive black hole at its core; however, this galaxy has largely ceased star formation, making it essentially "dead."

"We knew this galaxy was quenched based on previous observations - it isn't forming stars as expected for its size. Yet, until Webb, we couldn’t study it in detail to confirm a link between the black hole and halted star formation, nor determine if this state is temporary or permanent," Dr. Francesco D’Eugenio from the Kavli Institute for Cosmology, quoted as saying in a statement released by the University of Cambridge.

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Named GS-10578, or "Pablo's Galaxy" after a team member who selected it for in-depth study, this galaxy is massive for its era, with a total mass about 200 billion times that of the Sun, and most of its stars formed around 12.5 to 11.5 billion years ago.

"In the early universe, most galaxies were rapidly forming stars, so finding such a large, dead galaxy at this time is fascinating," noted co-author Professor Roberto Maiolino, also from the Kavli Institute for Cosmology. "Whatever process halted star formation likely did so quickly, given the galaxy’s massive size."

Webb's observations revealed that the galaxy is expelling large volumes of gas at roughly 1,000 kilometers per second - fast enough to overcome the galaxy's gravity. These powerful outflows are driven by the black hole, effectively pushing out the gas the galaxy needs for star formation.

While "Pablo’s Galaxy" exhibits outflowing winds like other galaxies with accreting black holes, Webb identified a new component: colder, denser gas clouds that do not emit light but are visible to Webb due to their blocking of background light from the galaxy.

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The amount of gas ejected surpasses what the galaxy requires to sustain star formation, effectively "starving" it. The findings, co-led by the University of Cambridge and published in the journal Nature Astronomy, point to the black hole as the "culprit,"

D’Eugenio said, "The black hole is effectively killing the galaxy, keeping it dormant by cutting off the fuel it needs to form new stars."

Earlier models had theorized that black holes could end star formation in galaxies, but direct evidence was lacking before Webb. Theoretical models also suggested that halting star formation would cause turbulence, potentially disrupting galaxy shape. However, the stars in this disc-shaped galaxy remain in orderly motion, indicating this disruption may not always occur.

It's no clear yet how much time GS-10578 still has or had before becoming history.

This study received support from organizations including the Royal Society, the European Union, the European Research Council, and the Science and Technology Facilities Council (STFC), a part of UK Research and Innovation (UKRI).

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