Their nature is yet to be known.
A group of astrophysicists recorded an unusual radio burst FRB 20190520B back in 2019. And now, as it turned out, they managed to catch this signal again.
Fast radio bursts are encountered by scientists periodically. But the fact is that usually they are of a single nature and each new such signal is new, not related to the previous one. And even such bursts are very difficult to detect, since they last no more than a few milliseconds.
The situation with FRB 20190520B is all the more interesting. It was first spotted three years ago with the FAST radio telescope in China. And then experts discovered permanent radiation associated with it.
It is reported that the most likely place where the signals come from is a dwarf galaxy at a distance of about 3 billion light-years from us.