Fast Radio Bursts
Most likely Fast radio bursts are phenomena of extragalactic origin. The nature of these impulses is still not clear. These events occur in a single pulse (two repeated except FRB121102 and FRB180814.J0422+73). The first fast radio burst was discovered in 2007 in the archive data of the Parks radio telescope (D. R. Lorimer et al.). The natural nature of this impulse was questioned (E. Petroff et al.). This question was removed after the detection of other pulses from different parts of the sky. The first repeating FRB has been registered wiht Arecibo radio telescope in 2012 (L. G. Spitler et al.). From this event, more than 30 impulses were recorded in the period from 2012 to 2017. This fact made it possible to identify FRB121102 with a place of intense star formation in a dwarf irregular galaxy, which is about 3 billion light years from the Earth.
The report of the second repeated event appeared at the beginning of 2019. CHIME Collaboration was able to register six pulses between August and October 2018 during its pre-commissioning phase in July and August 2018 (CHIME Collaboration).
Currently, the FRB Catalogue about a hundred FRB's events. The range of frequencies at which the pulses were observed varies from 111 MHz to 6.5 GHz. The high measure of dispersion and the galactic coordinates of the pulses indicate their extragalactic origin. There are a large number of models that describe the origin of such powerful pulses. A Living Theory Catalogue for Fast Radio Bursts was created by a group of scientists from different countries in 2018. Which of them is true we have yet to find out.