Using the Hubble Space Telescope, astronomers have mapped, for the first time ever, the plasma “burps” of a supermassive black hole-powered quasar that resides relatively close to Earth.
While supermassive black holes with masses millions or billions of times that of the sun are thought to reside at the heart of all galaxies, not all of these cosmic titans power quasars. Some, like the supermassive black hole at the heart of the Milky Way called Sagittarius A*, are relatively quiet because they don’t feed greedily on the matter around them.
This particular quasar and the predatory supermassive black hole that hosts it are located in the active heart of the Zwicky 1 galaxy, about 847 million light-years from Earth in the direction of the constellation Pisces. While this is an incredibly large distance, most quasars exist in the early universe, meaning they could be billions of light years away.
So the proximity of this quasar, called I Zwicky 1, makes it an excellent laboratory for studying the extreme conditions around active galactic nuclei (AGN), regions so bright that they can outshine the combined light of every star in the galaxy. the surrounding galaxies. those. This includes the “bumps” or outflows of matter from the surroundings of the supermassive black hole.
The supermassive black hole at the heart of Zwicky 1 is estimated to have a mass equal to 9.3 million Suns. It is thought to consume matter at an incredible rate and produce powerful jets that induce high-velocity “burps”. A team of astronomers from the Netherlands Institute for Space Research (SRON) described these leaks for the first time.
“Zwicky 1 is very special in its properties,” team leader Anna Juráňová said in a statement. “Other Khazars have similar outputs, but in this one, everything is in order. Our viewing angle, the width of the lines in the spectrum, and so on. This allows us to dig much deeper into its processes. We have created a global picture of the motions of ionized gas in a quasar, which is rare.”
How quasars get their outputs
Like all black holes, supermassive black holes are surrounded by an outer boundary called the event horizon. This is the point at which the gravitational influence of a black hole has become so intense that even light is not fast enough to meet its escape velocity.
Because nothing with mass can travel faster than the speed of light, it might lead you to wonder how these leaks escape quasars. The answer is that the material comprising the outputs never crosses the event horizon.
When a supermassive black hole is surrounded by matter, whether it’s gas and dust or the remains of a star that the black hole has torn apart with its immense gravity, that matter has angular momentum. This means it cannot fall directly into the black hole and instead forms a flat rotating cloud around the black hole called an “accretion disk”.
Matter in the accretion disk gradually feeds into the central supermassive black hole, but if there’s one thing scientists know about black holes, it’s that they’re messy eaters. Not all matter in accretion disks is destined to fall into the black hole; some charged particles are channeled to its poles by powerful magnetic fields.
These magnetic fields accelerate the trapped particles to speeds that are a significant fraction of the speed of light, and they then explode as closely aligned jets. These jets and their associated radiation push clouds of matter out from around the supermassive black hole, and these are the outputs the team mapped for I Zwicky 1.
Using Hubble, Juráňová and colleagues discovered the properties of four different plasma outflows from around I Zwicky 1. They found that they were moving at speeds between 134,000 mph (217,000 kph), 200 times the speed of sound, and a staggering 6.5 million mph (10.5 million km/h), which is about 8,500 times the speed of sound and about 1% of the speed of light.
The team also found that one of the leaks appears to be “caught in the shadow” of another black hole burp. This happens as radiation from the accretion disk in the form of ultraviolet light is absorbed by elements such as nitrogen, oxygen and carbon in clouds of matter in the vicinity of the black hole and pushed away as a result.
Not only is this the first time astronomers have seen this mechanism at play, it reveals to researchers that I Zwicky 1’s immediate surroundings are more active than the AGN homes of other quasars.
“Our data suggest that much more gas is being accreted and ejected from the disk around the black hole,” concluded Juráňová. “Having this knowledge brings us closer to discovering how these supermassive black holes grow and interact with their environment.”
The team’s research was published online Tuesday (June 11) in the journal Astronomy & Astrophysics.