Astrophysicists from York University have discovered the fastest winds ever seen at ultraviolet wavelengths near a supermassive black hole. These are not normal winds as their colossal speeds reach in excess of 200 million kilometers an hour.
Jesse Rogerson, who led the research as part of his PhD thesis in the Department of Physics and Astronomy at York University, said in a statement:
“We’re talking wind speeds of 20 percent the speed of light, which is more than 200 million kilometers an hour. That’s equivalent to a category 77 hurricane.
“And we have reason to believe that there are quasar winds that are even faster.”
Since the late 1960s, astronomers had been aware of the existence of quasar winds, with no less than one in four quasars having them. Quasars are the discs of hot gas that form around supermassive black holes that sit at the center of massive galaxies.
This video below from NASA illustrates how black-hole feedback works in quasars. The dense gas and dust within the center simultaneously fuels the black hole and shrouds it from view. The black-hole wind then propels large-scale outflows of cold gas that powers a shockwave that clears gas and dust from the central galaxy.
They produce enough light that they can be seen across the observable universe, are hotter than the surface of the sun, and larger than Earth’s orbit around the sun. York University Associate Professor Patrick Hall said:
“Black holes can have a mass that is billions of times larger than the sun, mostly because they are messy eaters in a way, capturing any material that ventures too close.
“But as matter spirals toward a black hole, some of it is blown away by the heat and light of the quasar. These are the winds that we are detecting.”
To identify new outflows from quasars, the team of astrophysicists used data from a large survey of the sky, known as the Sloan Digital Sky Survey.
After finding around 300 examples, they then designated about 100 for further examination. More data was collected using the Gemini Observatory’s twin telescopes in Hawaii and Chile.
“We not only confirmed this fastest-ever ultraviolet wind, but also discovered a new wind in the same quasar moving more slowly, at only 140 million kilometers an hour. We plan to keep watching this quasar to see what happens next,” Hall said.
The main reason for the research is to gain a better understanding of outflows from quasars and why they happen. Rogerson explains:
“Quasar winds play an important role in galaxy formation. When galaxies form, these winds fling material outward and deter the creation of stars. If such winds didn’t exist or were less powerful, we would see far more stars in big galaxies than we actually do.”
The findings were published in the Monthly Notices of the Royal Astronomical Society.