Madison Reporter

Clouds of gas in a distant galaxy are being propelled at more than 10,000 miles per second by radiation from the supermassive black hole at the galaxy’s center. This discovery sheds light on how active black holes can shape their galaxies by influencing star formation.

A team led by University of Wisconsin–Madison astronomy professor Catherine Grier and recent graduate Robert Wheatley revealed the accelerating gas using data collected over several years from a quasar, a bright and turbulent type of black hole, billions of light years away in the constellation Boötes. The findings were presented today at the 244th meeting of the American Astronomical Society in Madison.

"These quasars are really luminous," said Grier. "Because there’s a large range of temperatures from the interior to the far parts of the disk, their emission covers almost all of the electromagnetic spectrum."

Researchers utilized over eight years of observations from a quasar named SBS 1408+544, gathered by the Sloan Digital Sky Survey's Black Hole Mapper Reverberation Mapping Project. They tracked gaseous carbon winds by detecting missing light absorbed by this gas. The absorption shifted further with each observation, indicating increasing velocity.

“That shift tells us the gas is moving fast, and faster all the time,” said Wheatley. “The wind is accelerating because it’s being pushed by radiation that is blasted off of the accretion disk.”

Previous suggestions about accelerating winds lacked extensive observational data. The new results came from about 130 observations over nearly a decade, allowing for high-confidence identification of increased velocity.

The winds could influence galaxy evolution significantly. "If they’re energetic enough, the winds may travel all the way out into the host galaxy," Wheatley explained.

Depending on conditions, these winds could either promote star formation or prevent it by removing necessary fuel.

“Supermassive black holes are big but tiny compared to their galaxies,” Grier noted. “This is a way for one to talk to the other that we will have to account for when we model these kinds of black holes.”

The study was published today in The Astrophysical Journal and included collaborators from York University, Pennsylvania State University, University of Arizona, among others. It was funded partly by grants from the National Science Foundation (AST-2310211 and AST-2309930).