A weird cosmic flare called the ‘Cow’ now has company
First, astronomers discovered the “Cow.” Now they’ve rounded up a small herd. A short-lived celestial flare-up with a bovine nickname has been joined by two similarly unusual outbursts. The mysterious events were brighter than typical supernovas, explosions of stars that are a common source of temporary light shows in the sky. And the novel bursts came and went quickly, with their visible light brightening and dimming over days instead of the weeks typical of normal supernovas. As particularly luminous examples of a poorly understood class known as fast blue optical transients, the three novel bursts have unknown origins. But they seem to be kin. “It’s like people going out to find different creatures and find out how they’re related to each other. We’re in the early stages of the ‘zoology’ of this class,” says astronomer Anna Ho of Caltech. Detected in June 2018, the Cow earned its moniker thanks to the automatically assigned letters within its official astronomical name, “AT2018cow.” It is joined by the...