New images show how black holes produce incredibly bright jets millions of light years long that can be seen at vast cosmic distances.
The images were obtained using computer simulations and can help solve the mystery of how jets are formed.
Despite the name, black holes are not always black. As the black hole engulfs an object, the gas and dust swirling around heats the material around the edges to scorching temperatures. This process creates beacon-like beams of charged particles that travel outward at a speed close to the speed of light, emitting radiation that can shine brighter than a galaxy. “They are like laser beams that pierce the universe and allow us to see black holes, whose radiation otherwise it would be too dim to detect,”said astrophysicist Alexander Chekhovskoy of Northwestern University in Evanston, Illinois.
But the complex mechanisms behind these jets remain poorly understood. A potential understanding of the problem stems from the fact that the material around the black hole turns into plasma. Physicists have long suspected that the tortuous magnetic fields somehow interact with the curved fabric of spacetime around the spinning black hole, causing jets to appear. Using highly detailed computer models, Kyle Parfrey of NASA's Goddard Space Flight Center in Greenbelt, Maryland, and his colleagues were able to model how charged particles near the edge of a black hole cause magnetic fields to twist and spin. Scientists used information from Albert Einstein's theory of relativity to model pairs of these particles flying in special orbits. These orbits are tuned so that if one of the duo particles falls into a black hole,her partner will move at a very high speed, pushing herself using energy stolen from the black hole itself.
Any object, even a bag of debris, can be dropped from a spacecraft into one of these orbits, and this will give the spacecraft a powerful charge of energy, according to Chekhovskoy, who was not involved in the work. New computational methods will help researchers better study areas of intense electric current near the edges of the black hole, which can be associated with X-rays and gamma rays seen in the jets. The team then wants to model the generation of pairs of charged particles more realistically. This will allow astronomers to better predict the properties of the jets, Parfrey said.
The findings will also help scientists interpret the results of two studies, the Event Horizon telescope and the GRAVITY telescope, which are currently photographing the shadow cast on surrounding material by a supermassive black hole in the center of the Milky Way, Parfrey said.