Astronomers Identify Brightest Fast Radio Burst from Nearby Galaxy

A team of astronomers has successfully identified the brightest fast radio burst (FRB) ever recorded, tracing its origin to a nearby galaxy. This discovery marks a significant advancement in the understanding of these enigmatic cosmic phenomena, which have puzzled scientists for nearly two decades. The burst, designated as FRB 20250316A, was detected in March 2023 using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope located in British Columbia.

The flash emitted more energy in a matter of milliseconds than the Sun produces in four days. Researchers have long theorized that FRBs originate from violent cosmic events, such as collisions between neutron stars. Until this discovery, pinpointing the exact source of these bursts proved challenging. Bryan Gaensler, co-author of the study and dean of the UC Santa Cruz Science Division, likened previous attempts to identifying a caller without knowing their location: “We were detecting lots of FRBs, but only had crude information on where they were occurring in the sky,” he explained.

Unveiling the Source of RBFLOAT

The exceptional brightness of this FRB, nicknamed RBFLOAT for “Radio Brightest Flash Of All Time,” allowed astronomers to narrow down its location to a compact region approximately 45 light-years across, situated in the outskirts of a galaxy about 130 million light-years away. The burst occurred along a spiral arm of the galaxy, which is rich in star-forming regions, though it originated near, rather than inside, one of these areas.

Wen-fai Fong, a senior author on the study and professor of physics and astronomy at Northwestern University, expressed excitement about the findings: “It is remarkable that only a couple of months after the full Outrigger array went online, we discovered an extremely bright FRB in a galaxy in our own cosmic neighborhood.”

The detection was significantly aided by CHIME’s newly completed “outrigger” telescope array, which spans across North America from British Columbia to West Virginia. This enhanced network enables the detection of ultrafast, bright radio flashes with unprecedented sensitivity.

Investigating the Cosmic Mystery

Following the burst, researchers utilized data from the Keck Cosmic Web Imager on the 10-meter Keck II Telescope in Hawaii to further investigate RBFLOAT’s surroundings. This analysis included assessing the physical properties of the gaseous environment from which the FRB originated, including the rate of star formation and the density of gas in the region.

Despite these advancements, the precise cause of the flash remains uncertain. The research team speculates that RBFLOAT was produced by a magnetar, a type of highly magnetized neutron star that forms after a supernova explosion. Yuxin “Vic” Dong, a graduate student at Northwestern and co-author of the study, noted the intriguing location of the FRB outside the nearest star-forming clump. “This could suggest that the progenitor magnetar was kicked from its birth site or that it was born right at the FRB site and away from the clump’s center,” Dong explained.

With the CHIME Outriggers now operational, astronomers anticipate discovering more FRBs each year, potentially bringing humanity closer to unraveling the mysteries of these cosmic events. Amanda Cook, a postdoctoral researcher at McGill University and study author, remarked on the significance of this breakthrough: “This result marks a turning point. Instead of just detecting these mysterious flashes, we can now see exactly where they are coming from.” This development opens the door to understanding whether FRBs are caused by dying stars, exotic magnetic objects, or phenomena yet to be explored.