Astronomers have recorded repetitive radio signals from deep space. The repeating fast radio bursts (FRBs), which come from a galaxy 1.5 billion light-years away from Earth, is the second to be ever detected by mankind.
Deborah Good, from the University of British Columbia in Vancouver, reported at a meeting of the American Astronomical Society in Washington on Jan. 7, that the Canadian Hydrogen Intensity Mapping Experiment (CHIME) at the Dominion Radio Astrophysical Observatory in British Columbia detected 13 FRBs from July to August last year.
The telescope was originally designed to explore the early universe, but it has turned out to be an ideal instrument for detecting FRBs.
FRBs remain a mystery for scientists. The phenomenon is believed to release enormous amount of energy, but it isn't yet clear what causes them.
Theories as to what causes these millisecond-long radio flashes include neutron stars merging together, a neutron star with strong magnetic field that spins very fast, and even intelligent alien civilizations.
Between 50 to 60 FRBs have been observed to date, but repeating bursts emanating from the same source had only been detected once prior to CHIME's discovery.
Second Known Repeating Fast Radio Bursts
The first repeating FRB, the so-called FRB 121102, was discovered by the Arecibo radio telescope in Puerto Rico in 2015.
FRB 180814.J0422+73 detected by CHIME is only the second one that repeats. It was recorded six times coming from a single location 1.5 billion light-years away.
"Of the 13 reported here, one event has the lowest dispersion measure yet reported, implying that it is among the closest yet known, and another has shown multiple repeat bursts," Good and colleagues wrote in their study.
Astronomers said the discovery of the second repeating RFBs suggests there could be more out there. They also said that finding more repeaters may shed light on the mysteries of this cosmic puzzle, which include where FRBs are from and what causes them.
"Imagine you saw a unicorn," said Shriharsh Tendulkar, from McGill University in Montreal. "Then suddenly you discover another one. You know now there is a population of these. There is hope for discovering a lot more."
The researchers reported their findings in two papers published in the journal Nature on Jan. 9.