China Sky Eye, the world’s largest single-dish radio telescope located in a mountain-ringed valley in has just made an exciting discovery. The Five-hundred-meter Aperture Spherical Radio Telescope or FAST has picked up mysterious repeating space signals known as a fast radio burst. These FRBs are brief but powerful pulses of energy from distant parts of the cosmos. One such FRB was first spotted in 2007 with more of them getting detected all the time.
But the FRB detection by FAST is exciting and unique because this fast radio burst is a repeater. Officially known as FRB 121102, this repeating signal was first detected in 2012 at the Arecibo Observatory in Florida and has been picked up several times since then. Researchers note that the mysterious signal has traveled about 3 billion light-years across the Universe to reach us.
Although astronomers have made some exciting progress in tracing FRBs recently, we still don’t know precisely what these signals are, or how they originate. Perhaps, they are caused by black holes or neutron stars called magnetars.
China’s FAST first latched on to FRB 121102 on August 30 and has since recorded dozens of later pulses exceeding more than 20 pulses on a single day on September 3. Thus, this is a particularly persistent FRB.
The 19-beam receiver on FAST is particularly sensitive to radio signals falling in the 1.05-1.45 GHz frequency range, and that makes it ideal for tracking FRB 121102.
More observations of these FRBs will improve our chances of working out exactly what they are. One theory suggests that FRBs are produced upon the disintegration of the crusts of certain types of neutron stars. Another suggestion posits that different FRBs, in fact, have different causes, explaining why FRB 121102 repeats while others don’t appear to do so. We are at any rate getting better at pinpointing where these mysterious bursts of electromagnetic radiation originate from.
The data gathered by FAST adds to the growing database of knowledge on these most intriguing of space phenomena. The team at FAST has already eliminated aircraft and satellite interference from their measurements to isolate the signal.
Physicist Ziggy Pleunis of McGill University told ScienceAlert, after assisting in listing eight new FRBs in a paper published last month, “I just think it is so amazing that nature produces something like that. Also, I think that there is some very important information in that structure that we just have to figure out how to encode and it has been a lot of fun to try to figure out what exactly that is.”