The very first on-off from a fast radio burst came in 2007, when astronomer Duncan Lorimer was sifting through archived data, searching for undiscovered pulsars. But instead, he found something that flashed just once, brighter than a pulsar and seemingly much farther away. He didn’t know what he was looking at. Neither did anyone else.

This is a familiar story arc in astronomy. It’s really the best way to find something utterly new: by accident, while searching for something known.