Webb Space Telescope Finds Ancient 'Dead' Galaxy

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Astronomers have discovered the oldest “dead” galaxy ever observed while studying the universe with the James Webb Space Telescope, and it's one of the deepest views of the distant universe ever made with the observatory.

The galaxy existed when the universe was only about 700 million years old compared to its current age of 13.8 billion years. But the galaxy suddenly stopped star formation 13 billion years ago, just as star birth began, and researchers have yet to figure out why.

A report detailing the discovery appeared in Wednesday's journal Nature. Studying galaxies can reveal new insights into the early universe and the factors that influence star formation within galaxies, the authors suggest.

“The first few hundred million years of the Universe was a very active phase, with lots of gas clouds collapsing to form new stars,” said lead study author Tobias Loeser, a PhD candidate in extragalactic astrophysics at the University of Cambridge's Kavli Institute for Cosmology. In a statement. “Galaxies need a rich supply of gas to form new stars, and the early universe was like an all-you-can-eat buffet.”

The research team was surprised to find a so-called dead galaxy that lived rapidly and died young very soon after the Big Bang that created the universe.

“(Typically) it's late in the universe that we start to see galaxies stop forming stars, either because of a black hole or something else,” said study co-author Dr Francesco D'Eugenio. Astronomical Institute, in a statement.

Star formation ceases when environmental factors starve the galaxy of the gas needed to seed the birth of new stars.

Violent interactions between supermassive black holes or stars may be the culprits in expelling gas from galaxies, which rapidly halts star formation. Or, the process of star birth may consume so much gas that there is not enough time to replenish enough to ensure that the process will continue into the future.

“We don't know if any of those scenes can explain what we've seen now with the web,” said Roberto Maiolino, professor of experimental astrophysics at the Cavendish Laboratory and the Kawli Institute for Cosmology at the University of Cambridge. A statement.

“Until now, to understand the early universe, we used models based on the modern universe. But now that we can look further back in time, and observe that star formation in this galaxy is quenching very quickly, models based on the modern universe may need to be rethought,” Maiolino said. He also said.

Web observations revealed that the newly discovered galaxy, named JADES-GS-z7-01-QU, experienced a short, energetic burst of star formation that lasted between 30 million and 90 million years before suddenly ceasing star birth.

“Everything seems to be happening fast and dramatically in the early universe, and that includes galaxies that are quiescent or quenching from the star-forming stage,” Loser said.

The dead galaxy revealed by the study is not the first astronomers have seen, but it is one of the oldest ever observed.

What's more, the galaxy is as low-mass as a dwarf galaxy near the Milky Way called the Small Magellanic Cloud—which still produces new stars. Previously observed dead galaxies were much more massive, adding another quirk to Webb's discovery.

The newly discovered galaxy is billions of light-years away from Earth, and a light-year is how far a light beam travels in one year, or 5.88 trillion miles (9.46 trillion kilometers). So Webb is observing the galaxy as it was in the past — and astronomers don't rule out that it may have essentially resurrected itself and started star formation anew.

“We're looking for other galaxies like this in the early universe, which could help put some constraints on how and why galaxies stop forming new stars,” Di Eugenio said. “Galaxies in the early universe 'died' and then came back to life – we'll need more observations to figure that out.”