The signal was thought to be a telescope artifact, a trick of light masquerading as a cosmic curiosity. The first FRB was discovered in 2007, buried deep in archival data of a telescope in Australia, while astronomers were looking for another astrophysical phenomenon. The discovery is an intriguing addition to a growing inventory of knowledge in a field whose earliest evidence was almost dismissed as a fluke. Read: What’s better than one mysterious cosmic signal? When Li and I spoke this week, she told me she’s still checking-and the rhythm is still there. Like so many people this year, Li has spent most of her days at home, rarely venturing beyond the walls of her small apartment in Bonn, Germany, but the Canadian observatory continues to scan the skies, catching the fleeting FRBs as little smudges of black against a plot of white noise. The paper on this discovery, published earlier this month, marked the end of formal observations in February. Astronomers traced the source to a spiral galaxy about 500 million light-years away, where it’s still going strong. The FRB, known by the bar-code-esque designation 180916.J0158+65, is the first to show this kind of regular cadence. (This is, perhaps, the purest definition of radio silence.) Li was monitoring FRBs, tracking their arrival times at a radio telescope in British Columbia, when she noticed that unusual pattern from one FRB source-four days on, 12 days off. In the past decade, astronomers managed to detect about 100 of them before they vanished. They show up without warning and flash for a few milliseconds, matching the radiance of entire galaxies.Īstronomers don’t know what makes them, only that they can travel for millions, even billions, of years from their sources before reaching us. She works on a Canadian-led project, CHIME, that studies astrophysical phenomena called “fast radio bursts.” These invisible flashes, known as FRBs for short, reach Earth from all directions in space. The pattern-the well-defined swings from frenzy to stillness and back again-persisted like clockwork for more than a year.ĭongzi Li, a doctoral student at the University of Toronto, started tracking these signals in 2019. Then, another four days of haphazard pulses. The findings brings astronomers a step closer to understanding the origins of these mysterious signals from outer space.For about four days, the radio waves would arrive at random. “Just like doing video calls with colleagues shows you their homes and gives you a bit of an insight into their lives, looking into the host galaxies of fast radio bursts gives us insights to their origins,” said Dr. Prochaska et al.įollow-up observations were made using some of the world’s largest optical telescopes, including Gemini South, the Very Large Telescope, Magellan Baade, Keck and the LCOGT-1m.Īlthough all of the four FRBs are coming from three or four billion light-years away, all were discovered to be coming from massive galaxies that are forming new stars at a modest rate, much like our own Milky Way. The analysis of these data revealed that the radio pulses have passed through the halo of a massive galaxy (at the top of the image) on their way toward Earth. fast radio burst, named FRB 181112, ESO’s Very Large Telescope (VLT) took this image and other data to determine the distance to its host galaxy (FRB 181112 location indicated by the white ellipses). Soon after the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope pinpointed a.
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