The black hole directs a particle beam at Earth

A black hole that sends a jet of particles towards Earth is called a blazar. Researchers are tracking this phenomenon with the help of NASA’s telescope.

Munich – There are many phenomena in the universe that are still not fully understood by researchers. These include black holes that shoot powerful jets of high-energy particles into space. When one of these rays is directed directly at Earth, science calls a black hole an explosion. Researchers have long known that high-energy particles move very quickly — almost the speed of light. However, the reason for this is still a big mystery.

To investigate this phenomenon more closely, a team led by astrophysicist Laura De Jesso aligned the NASA IXPE Space Telescope with a blazar called “Markarian 421.” Markarian 421 is an old friend of high-energy astronomers. De Gesu explainswho is the lead author of the study in the journal natural astronomy published had become. “We were sure that Blazar would be a useful target for IXPE, but the discoveries exceeded our highest expectations,” says the researcher.

The black hole sends a beam of particles towards Earth

Blazar rays like Markarian 421 can spread out over millions of light-years. They are particularly bright because the particles travel very quickly and release a large amount of energy along the way. In fact, blazars can outshine all the stars in the galaxy. What sounds scary means no danger to Earth in the case of Markarian 421: Blazar is located about 400 million light-years from Earth, in the constellation Ursa Major. Even if its particle beam were to point at Earth, it would not reach it.

To learn more about the characteristic blazars phenomenon, the research team used IXPE to study the polarization of the jet’s magnetic field, that is, its direction. Scientists have found a surprise: the particle beam emitted by Markarian 421 contains a magnetic field that has a spiral structure. “We expected that the direction of the polarization might change, but we thought that large spins would be rare based on previous optical observations of many blazars,” explains co-author Hermann Marshall. “So we tabulated several observations of the blazar, the first showing a constant polarization of about 15 percent.”

Blazar jet particles have a helical structure

On the second observation of the blazar, the polarization appeared to drop to zero. “Then we realized the polarization was almost the same, just the direction literally reversed and rotated about 180 degrees in two days,” Marshall said. “In the third observation, which started a day later, we were again surprised that the direction of polarization continues to rotate at the same rate.”

What surprised the research team even more was the fact that measurements in the optical, infrared and radio ranges showed no change in stability or structure. The research team led by De Jesu and Marshall now wants to make more observations of Markarian 421 and other blazars in order to learn more about the newly discovered phenomenon. “It’s an exciting time to study astrophysical jets thanks to IXPE,” said Di Jessu. (unpaid bill)