NEW HAVEN, Conn., Jan. 25 (UPI) -- In a newly published study, researchers at Yale have zeroed in on a strange-behaving quasar. This particular quasar is dimming. And astronomers say its changing look is a result of a dieting black hole.
Quasars are typically the brightest, most energy intense objects in the cosmos. But over the last several years, this quasar has toned it down a bit. Scientists have previously observed quasars -- which derive their energy from the cosmic materials sucked in and swallowed by black holes -- that are both bright and dim. But this the first time researchers have observed a shift in output from a single source.
"We've looked at hundreds of thousands of quasars at this point, and now we've found one that has switched off," study co-author C. Megan Urry, an astronomy professor at Yale, explained in a recent press release. "This may tell us something about their lifetimes."
The researchers say the sudden dimming is evidence that the quasar's energy-providing black hole has gone on a diet of sorts. It's consuming less energy, and is thus giving off less energy. Over the last six years, the quasar has dimmed by an order of seven magnitudes.
"This is like a dimmer switch," said lead researcher Stephanie LaMassa. "The power source just went dim. Because the life cycle of a quasar is one of the big unknowns, catching one as it changes, within a human lifetime, is amazing."
The new study may prove valuable in better understanding the lifecycle of black holes and quasars.
"It makes a difference to know how black holes grow," Urry added. "This perhaps has implications for how the Milky Way looks today."
The study is set to be published in the upcoming issues of The Astrophysical Journal.
"Even though astronomers have been studying quasars for more than 50 years," LaMassa said, "it's exciting that someone like me, who has studied black holes for almost a decade, can find something completely new."