China's Five-hundred-meter Aperture Spherical Radio Telescope (FAST) has detected arepeating fast radio burst (FRB) -- mysterious radio signals from outer space -- for the firsttime, Science and Technology Daily reported.


Scientists on the FAST project with the National Astronomical Observatories of China, part ofthe Chinese Academy of Sciences, revealed the news last Wednesday.


The FRB originated some three billion light years away from Earth. Interference factorsincluding aircraft and satellites have been eliminated and cross validation is being carried out, the scientists said.


FRB has since become one of the hottest topics in astronomy. It was not until 2007 when thefirst FRB was discovered by humans. Fewer than 100 FRBs have been detected internationallyto date.


There is still no cohesive explanation for the origin of FRB in the international scientificcommunity at present. FRBs mostly only appear once, which makes them very hard to track.


The FRB detected by FAST's real-time detection terminal, however, is one that has beenobserved before, said Zhang Xinxin, an assistant engineer with the NAOC.


Known as FRB121102, it was first discovered in 2012 and found to repeat in 2015. Analysis ofdata later located the source of the signal coming from a dwarf galaxy three billion lightyears away.


The first pulse from FRB121102 was spotted by FAST on Aug 30. After this, the telescoperecorded dozens of pulses from the FRB over the course of days. On Sept 3 alone, more than20 pulses were detected.


The number of enigmatic bursts detected so far is too small to draw any conclusions, Zhangsaid.


FAST, the world's largest single-dish radio telescope, has a certain edge in detecting repeatedFRBs. This is because the 19-beam receiver installed on FAST, covering frequency ranges of1.05 -- 1.45 GHz, is very sensitive to radio signals, Zhang said.