Massive jets of material shooting from a black hole dwarf even the largest galaxies, scientists say
Black holes are viewed as the garbage disposals of the universe, gobbling up nearly everything that comes close to them. However, a fraction of material is ejected before an object falls in, forming a jet on either side of the black hole.
Black hole jets can accelerate radiation and particles close to the speed of light, causing them to glow in wavelengths visible to radio telescopes. Such a glow drew the attention of astronomers behind the new study while they were surveying the sky using a radio telescope in 2018.
The newly described jets have a power output equivalent to that of trillions of suns and are so massive that researchers have nicknamed the megastructure Porphyrion after a giant from Greek mythology.
The discovery is causing astronomers to rethink their understanding of how massive black hole jets can be as well as how these giant features can affect their surroundings and the structure of the universe.
Initially, the researchers were looking for the wispy filaments of the cosmic web, which is the large-scale structure of the universe - a network of matter that pervades all the space between galaxies. While seeking to observe the cosmic web, the team discovered large jets coming from galaxies. In total, the team spotted 10,000 new black hole jet pairs.
Supermassive black holes lie at the centers of large galaxies. The team’s observations highlighted that an increasing number of galaxies have black hole jets reaching far beyond their borders.
Before these observations, large jet systems were thought to be rare and expected to be smaller in size. The researchers now believe it’s possible to find jets larger than Porphyrion as radio telescope technology improves.
Follow-up observations pointed to a distant galaxy about 10 times more massive than the Milky Way as the origin of the jets. The data also revealed that the structures came from a radiative-mode active black hole, rather than the type known to produce larger jets, which surprised the researchers.
Understanding how long giant black hole jets have existed during the universe’s 13.8 billion years could help astronomers find out how the jets have influenced their surroundings. Two big questions facing astronomers are how the universe became magnetized and how the cosmic web’s large-scale structures that lie between galaxies came to be. The massive black hole jets could help answer both.
If sustained for millions of years, powerful black hole jets can affect the flow of matter through intergalactic space by releasing charged particles and magnetic fields through space. The team’s research shows that Porphyrion was able to heat its surroundings in intergalactic space by about 1 million degrees.
The team continues to investigate how the black hole jets can extend so far beyond their host galaxy without becoming unstable. The discovery reveals an exciting “fossil record” of supermassive black hole activity that can show how the jets and black hole have evolved over time.
Porphyrion may have also magnetized its local environment, and researchers want to understand how massive jets could spread magnetism through the cosmic web. The origin of magnetism is key because magnetic fields, like the one surrounding Earth, can protect and shield a life-sustaining atmosphere.