popsci.com – By Mary Beth Griggs – Of all the weirdness in the universe, fast radio bursts (FRBs) are among the weirdest. Sure, possible (probably not) alien megastructures might beat them in an astrophysical brawl, but FRBs are really strange. How strange are they? Well, they are intense bursts of radio waves only last for an instant (thousandths of a second), only 20 of them have ever been noticed, and we’ve only potentially pinpointed the galaxy of origin for one of those 20 or so FRBs. Adding to their mysterious allure, that last location is currently a hot topic of debate. We basically have no idea what they are, or where they come from. For a long time, scientists thought they might be caused by explosions or collisions of distant stars. Then, one of the FRBs got put on repeat. Usually, an FRB only happens once, a single burst coming from an unknown part of the sky, but in a paper published this week in Nature researchers found a repeating sequence of a total of 10 FRBs.