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Clouds of gas in a distant galaxy are being pushed faster and faster — at more than 10,000 miles per second — among neighboring stars by bursts of radiation from the supermassive black hole at the center of the galaxy. It’s a discovery that helps illuminate how active black holes can continually shape their galaxies by stimulating or suppressing the development of new stars.

A team of researchers led by University of Wisconsin-Madison astronomy professor Catherine Greer and recent graduate Robert Whitley discovered the accelerating gas using years of data collected from a quasar, a particularly bright and turbulent type of black hole, billions of light-years away. us in the constellation Volovar. They presented their findings today at the 244th meeting of the American Astronomical Society in Madison.

Scientists believe that black holes are located at the center of most galaxies. Quasars are supermassive black holes surrounded by disks of matter pulled by the black hole’s immense gravitational pull.

“The material in that disk is always falling into the black hole, and the friction from that tugging and tugging heats the disk and makes it very, very hot and very, very bright,” says Greer. “These quasars are really luminous, and because there is a large range of temperatures from the interior to the far reaches of the disk, their emission covers almost the entire electromagnetic spectrum.”

The bright light makes visible quasars that are nearly as old as the universe (up to 13 billion light years), and the wide range of their radiation makes them particularly useful for astronomers studying the early universe.

The researchers used more than eight years of observations of the quasar, called SBS 1408+544, collected by a program carried out by the Sloan Digital Sky Survey, now known as the Black Hole Mapper Reverberation Mapping Project. They tracked winds made up of gaseous carbon, spotting light from the quasar that was missing — light that was absorbed by the gas. But instead of being absorbed in exactly the right spot in the spectrum, which would indicate carbon, the shadow moves further from home with each new look at SBS 1408+544.

“This change tells us that the gas is moving fast and faster all the time,” Wheatley says. “The wind accelerates because it is pushed by radiation that is ejected from the accretion disk.”

Scientists, including Greer, have suggested that they have observed accelerating winds from the accretion disks of black holes before, but this has yet to be supported by data from more than a few observations. The new results came from about 130 observations of SBS 1408+544 made over nearly a decade, allowing the team to identify the solid speed increase with high confidence.

The winds that expel gas from the quasar are of interest to astronomers because they are a way that supermassive black holes can influence the evolution of the galaxies that surround them.

“If they are energetic enough, the winds can propagate all the way into the host galaxy, where they could have a significant impact,” Whitley says.

Depending on the circumstances, the quasar’s winds can provide pressure that squeezes gas together and accelerates the birth of a star in the host galaxy. Or it could scavenge that fuel and prevent a potential star from forming.

“Supermassive black holes are big, but they’re really small compared to their galaxies,” says Greer. “That doesn’t mean they can’t ‘talk’ to each other, and it’s a way for one to talk to the other that we’ll need to account for when we model the effects of these types of black holes.”

The study of SBS 1408+544, published today in The Astrophysical Journal included collaborators from York University, Pennsylvania State University, University of Arizona, and others.