Rare link between black hole and gas cloud in Milky Way discovered, scientists say their 'heartbearts' are synced
In our Milky Way galaxy, about 15,000 light-years away, astronomers have intercepted a mysterious interaction between two far-off bodies: cosmic gas cloud and a black hole. What is more, both of them have their "heartbeats" following a similar rhythm, according to a new study.
The heartbeats in the cosmic gas cloud and the black hole are gamma-rays, which are synced. In other words, the rays periodically go bright and dim, Dr. Jian Li, DESY Humboldt Fellow, told MEA WorldWide (MEAWW). Experts are trying to understand the connection between the two objects, which are separated by 100 light-years.
The black hole in question is about 10 to 20 solar masses. It sucks materials from its companion giant star. The duo behaves like a smaller version of a quasar -- a supermassive black hole that eats up its surrounding matter -- earning the name, microquasars. Both bodies orbit each other.
The microquasar system is named SS 433. "As the material – dust and gas – from the companion star falls on the black hole, it forms a disc around it. We call this disk accretion disk," Dr. Li explained. "The material accumulates in an accretion disc before falling into the black hole, like water in the whirl above the drain of a bathtub." However, a part of that matter shoots out as two jets in opposite directions, he added.
The jets move similar to how a top spins on a table. It is here that gamma rays are produced. Using NASA's Fermi gamma-ray space telescope, a team of scientists from Germany, Spain, China, and the US studied the microquasar system. The satellite scans the universe to collect information on gamma-ray bursts, black-hole jets to pulsars, supernova remnants, and the origin of cosmic rays, according to NASA. They also deployed a radio telescope called Arecibo Observatory for the study. It recently suffered an accident and is not functional.
The team detected the same gamma radiation, about 100 light-years away, in the gas cloud. The cosmic cloud's gamma-ray heartbeat is consistent with that of the jet, Dr. Li said of the analysis. "The particles can come from microquasars and reach the clouds to produce gamma rays," he explained. "This is possible, but this cannot produce this periodic heartbeat. This is very difficult," he added.
Besides, the jet does not lie on the path of the cloud. "This is quite weird," Dr. Li noted, adding that it does not explain the syncing heartbeats. So what could be driving it? According to him, an outflow from the jet could be hitting the cloud. The interaction produces gamma rays, which could explain the strange heartbeat and matching rhythms. Alternatively, magnetic connections could enable the particles to move to the cloud.
However, this theory is not foolproof. For this, "we require the cloud to be very dense. We also require some connections between the cloud and the central object. However, none of them are confirmed," he said. The study suggests that microquasars could play a bigger role in the production of cosmic rays. But this is speculation at the moment. We have to prove it, Dr. Li said.
The study is published in Nature Astronomy. You can find a video of microquasars here.