The discovery doubles the known population of these repeating super-energetic cosmic explosions.

Astronomers have doubled the known number of repeating rapid bursts of powerful radiation emanating from distant galaxies outside the Milky Way.

These blasts, known as fast radio bursts (FRBs), are so powerful they can outshine the entire galaxy from which they emerge. But despite this incredible power, the origins of FRBs are mysterious.

In a new study, a team led by astronomers from the Canadian Hydrogen Intensity Mapping Experiment (CHIME)/FRB Collaboration and the University of Toronto found 25 new repeating FRBs, bringing the total known to 50. This could lead scientists to the discovery of what causes these bursts and also suggests that many more FRBs could eventually repeat than previously thought, team members said. Astronomers have discovered many FRBs over the last decade, but the vast majority of these have been non-repeating and were only seen to “burst” once. Only a small fraction have been seen to repeat. This has led astronomers to question if repeating FRBs and non-repeating FRBs come from the same sources.

The fact that these two populations of FRBs seem to have different characteristics — including how long they last and the range of frequencies they are seen across — also points to their varied origins. Key to confirming this is the discovery of more repeating FRBs, which the team involved in this research did by developing a new set of statistical tools and combing through data to analyze every repeating FRB ever seen, including ones that aren’t immediately obvious. “We can now accurately calculate the probability that two or more bursts coming from similar locations are not just a coincidence,” study team member Ziggy Pleunis, a postdoctoral fellow at the University of Toronto’s Dunlap Institute for Astronomy and Astrophysics, said in a statement(opens in new tab). “These new tools were essential for this study, and will also be very useful for similar research going forward.”

- Space