This Black Hole Is Wildly Ejecting Plasma Jets as It Eats a Star
"This is one of the most extraordinary black hole systems I've ever come across.”
Concept art depicting V404 Cygni. Image: ICRAR
There is a black hole 8,000 light years away that is acting weird, even for a black hole, scientists say.
Called V404 Cygni, the system contains a black hole and a star like our Sun. The hole is tearing off hot material from the star and then firing it out at various angles at light speed.
While black holes with companion stars often eject plasma from their poles, this marks the first time astronomers have witnessed jets shot in many different directions on short timescales.
The unusual behavior is detailed in a paper published Monday in Nature. Led by James Miller-Jones, an astronomer at the International Centre for Radio Astronomy Research (ICRAR), the authors suggest that the jets might be caused by the black hole’s off-kilter relationship with its companion star.
"This is one of the most extraordinary black hole systems I've ever come across," Miller-Jones said in a statement. Like other black holes that feed on stars, this object pulls in material that accumulates in an accretion disk. But unlike other holes, the plane of the disk and the hole may be “misaligned,” Miller-Jones said.
“This appears to be causing the inner part of the disk to wobble like a spinning top and fire jets out in different directions as it changes orientation," he explained.
The unstable dynamics cause the system to flare up in ultra-luminous outbursts that can last weeks. When V404 Cygni suddenly got brighter again in 2015, the astronomical community was ready to take a more detailed look at the event.
"Everybody jumped on the outburst with whatever telescopes they could throw at it so we have this amazing observational coverage," Miller-Jones said.
Using observations from the Very Long Baseline Array, a network of ten radio telescopes around the US, Miller-Jones and his colleagues were able to capture the black hole firing off jets at different orientations, sometimes just minutes or hours apart.
The black hole portion of V404 Cygni was first discovered during one of these energetic light shows, in 1989. Astronomers were able to track down two other outbursts in 1938 and 1956 using archival images.
While V404 Cygni seems pretty strange to scientists now, future observations may find that these misaligned, trigger-happy back holes are more common than we thought.
Get six of our favorite Motherboard stories every day by signing up for our newsletter.