Evidence has always been scarce, until recently. The signals only last for a millisecond each, according to the Independent, but each one is flung through the galaxy with the same amount of energy the sun produces in 12 months. What in the Universe is going on?
Ingrid Stairs, an astrophysicist at the University of British Columbia, gave her take on it:
"Until now, there was only one known repeating FRB . Knowing that there is another suggests that there could be more out there. And with more repeaters and more sources available for study, we may be able to understand these cosmic puzzles — where they’re from and what causes them."
Scientists believe that finding these repeating signals means they will eventually find a ‘substantial population’ of such signals.
Cherry Ng, an astronomer at the University of Toronto, said:
"That could mean in some sort of dense clump like a supernova remnant, or near the central black hole in a galaxy. But it has to be in some special place to give us all the scattering that we see."
In a short three-week period, researchers detected a total of 13 fast radio bursts, providing them with more information on the subject than ever before. Scientists are hoping to use this data to uncover where the signals have come from. Crucially, they want to know whether they are naturally or spontaneously occurring, or whether they have been purposefully created.
Arun Naidu of McGill University said:
"Whatever the source of these radio waves is, it’s interesting to see how wide a range of frequencies it can produce. There are some models where intrinsically the source can’t produce anything below a certain frequency."
The new signals were discovered by the Canadian Hydrogen Intensity Mapping Experiment (CHIME), in British Columbia, Canada.
Of the 13 blasts picked up by CHIME, at least seven were at the lowest frequency of any detected so far, at 400 MHz. This would suggest that there are more blasts to be picked up, but are undetected at the moment, as their frequencies are too low.
Tom Landecker, a CHIME team member from the National Research Council of Canada, said:
" the sources can produce low-frequency radio waves and those low-frequency waves can escape their environment, and are not too scattered to be detected by the time they reach the Earth. That tells us something about the environments and the sources. We haven’t solved the problem, but it’s several more pieces in the puzzle."
All of this is very exciting, but as it stands, even the brightest boffins don't yet know what is causing the signal blasts. Watch this space, folks!