Astronomers have spotted a distant galaxy that is “stuck” at the moment of “shutdown.” The study is published by The Astrophysical Journal.
The galaxy, dubbed CQ 4479, is still forming many new stars. At the same time, there is also an actively feeding supermassive black hole in its center. It could already have stopped star formation in the galaxy. However, this will happen in a few hundred million years, astronomers said at a virtual meeting of the American Astronomical Society. Studying this and other galaxies will help scientists figure out exactly how such “shutdowns” of galaxies occur.
“How exactly galaxies die is an open question,” said astrophysicist Allison Kirkpatrick of the University of Kansas at Lawrence. “Object CQ 4479 can help us better understand this process.”
According to the main theories, the formation of stars in galaxies is stopped due to the influence of a supermassive black hole located in the center, or due to a mechanism that is currently unknown. Galaxies begin to fade in the center, and then this process spreads to the periphery. At the edges of galaxies, stars fade out much longer than those in the center.
Nonetheless, observations of CQ 4479 support general notions of how galaxies die, astronomer Alexandra Pope of the University of Massachusetts Amherst, who was not involved in the new work, said in an interview with Science News. Given that galaxies end up shutting down their star formation, it makes sense that there should be a transition period. The findings are “confirmation of this important phase in the evolution of galaxies,” she is sure. A closer look at the coldest quasars in galaxies will help astronomers figure out how quickly star factories are dying.