The home galaxy of a second repeating fast radio burst is a puzzle
Brief, brilliant flashes of radio waves have been traced back to a galaxy that looks like the Milky Way — a radically different environment from where astronomers have seen similar radio flares before. Until now, the only source known for a recurrent fast radio burst like this was a tiny, star-forming dwarf galaxy (SN: 1/4/17), while nonrepeating bursts have been tracked back to more massive, mellow galaxies. That implied that the two varieties of fast radio bursts, or FRBs, might have different sources (SN: 6/27/19). But astronomers have pinned a second repeating FRB to an entirely different kind of host galaxy: a star-forming spiral, similar in size to our own galaxy, about 500 million light-years away. That observation, reported online January 6 in Nature, suggests that a whole menagerie of galactic environments may generate FRBs. “There needs to be a theory that can explain this diversity of environments, or … there are multiple different sources for fast radio bursts,” says Jason Hessels, an...