Astronomers have detected eight repetitive radio signals known as fast radio bursts (FRBs). Their sources are still unknown. This is reported by Science Alert.
Two sources of radio signals - FRB 180916 and FRB 181119 - flashed more than two times (ten and three times, respectively), the rest sent repeated radio signals only once, with the longest pause between the registration of radio waves being 20 hours. According to the researchers, this may indicate that many FRBs are repetitive, but some are more active than others.
Most of the eight new fast radio bursts show a decrease in signal frequency with each repeated burst, which may be clues to the mechanism that produces them. In addition, FRB 180916 has the lowest signal dispersion rates, indicating the relative proximity of the source to Earth. It can also help determine the nature of the radio burst.
The fast radio burst continues for several milliseconds and is accompanied by the release of a huge amount of energy into space. A number of scientists believe that bursts may be the result of catastrophic events - for example, the death of stars. However, some radio pulses are repeated over time. For example, FRB 121102, which is believed to be a neutron star, gave signals in 2012 and 2015-2017.