Scanning the skies from Down Under, a team of astronomers detected an enigmatic burst of radio energy unlike anything that has been seen before. Thousands of light-years away, a distant object smaller than our sun was observed emitting pulsating radio light, which was not strange itself; what was unique about these intermittent flashes was the the unusually slow intervals between them. Astronomers have known for a long time about objects that appear and then disappear in outer space; such phenomena are called transients. The slow, gradual appearance of gamma ray afterglows or the events of supernovae come and then go over the course of days or months—these are slow transients. Other objects may flash on and off at a quick, steady clip measured in seconds or milliseconds—these fast transients include pulsars and white dwarfs. However, this new curiosity spotted in Australia flicked off and on at previously unheard-of rhythms: emitting …