This artist’s rending shows “before” and “after” images of a changing look quasar.
Michael S. Helfenbein
Yale University astronomers have identified the first “changing look” quasar, a gleaming object in deep space that appears to have its own dimmer switch.
The discovery may offer a glimpse into the life story of the universe’s great beacons.
Quasars are massive, luminous objects that draw their energy from black holes. Until now, scientists have been unable to study both the bright and dim phases of a quasar in a single source.
Yale-led researchers spotted a quasar that had dimmed by a factor of six or seven, compared with observations from a few years earlier.
“We’ve looked at hundreds of thousands of quasars at this point, and now we’ve found one that has switched off,” said C. Megan Urry from Yale. “This may tell us something about their lifetimes.”
