By denying galaxies the gas necessary for star formation, supermassive black holes can effectively stop their growth, as demonstrated by astronomers using the NASA/ESA James Webb Space Telescope. An international team known as “Pablo’s Galaxy,” or GS-10578, researched a galaxy from roughly two billion years after the Big Bang. The team was partially directed by the University of Cambridge. Pablo’s Galaxy resembles the Milky Way in size, but it is almost “dead,” since it is no longer producing new stars.
Dr. Francesco D’Eugenio from the Kavli Institute for Cosmology explained that while previous observations indicated this galaxy was in a star-forming “quenched” state, the James Webb Space Telescope offered new insights. “We haven’t been able to study this galaxy in enough detail to confirm the link between the black hole and the end of star formation,” he noted. With a mass 200 billion times that of the Sun, most of the galaxy’s stars formed between 12.5 and 11.5 billion years ago.
Using Webb’s advanced capabilities, astronomers discovered that the supermassive black hole at the galaxy’s core is expelling gas at 621 miles per second (1,000 kilometers per second), or 2,235,600 miles per hour. This gas ejection is powerful enough to escape the galaxy’s gravitational pull, depriving it of the material needed to form stars. Interestingly, the expelled gas includes colder, denser components that emit no light, which were invisible to previous telescopes.
“This discovery is critical,” said D’Eugenio, confirming the role of the black hole in stifling the galaxy’s star formation. Future observations using the Atacama Large Millimeter-Submillimeter Array (ALMA) will aim to study the coldest gas remaining in the galaxy to further understand the black hole’s impact.
