Astronomers discover likely source of strange radio bursts from space
For more than 13 years, astronomers have been trying to determine the source of extremely powerful radio bursts that can travel billions of kilometres through space but only last a fraction of a second.
These signals — called fast radio bursts (FRBs) — were discovered in 2007 by two astrophysicists while poring through data collected in 2001 from the Parkes Observatory in New South Wales, Australia. Since then, dozens more have been detected, even a different form called repeating fast radio bursts.
But just what is responsible for pumping out these extremely bright radio signals has remained shrouded in mystery, with even the odd whisper of whether or not it was astrophysical in the first place.
Three independent teams of international astronomers, who published three separate papers in the journal Nature Wednesday, have found one likely culprit: magnetars.
Magnetars are a fascinating type of neutron star, the collapsed core of a massive star that exploded. They are spheres that are roughly the size of a city like Toronto or Montreal, but so dense that a piece of material the size of a sugar cube would weigh as much as a mountain, or one trillion kilograms.
But a magnetar takes a neutron star to the extreme. While the magnetic field of a neutron star is trillions of times stronger than Earth’s, a magnetar’s is 1,000 times more than that.
Over the past decade or so, there had been several theories as to what could produce FRBs, one of which was a magnetar. But the sources of the brief but powerful signals were too far away to confirm.
But on April 28, astronomers using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope in Penticton, B.C., and the Survey for Transient Astronomical Radio Emission 2 (STARE2) telescope captured an FRB burst from the same region of the sky. The pair of telescopes were able to confirm that it had been emitted from SGR 1935+2154, a known magnetar.