Since they were discovered in 2019, strange, glowing circles of light in space have mystified researchers. Now called odd radio circles, or ORCs, these rings of light sit in the radio portion of the electromagnetic spectrum. They pulse out of the centers of some galaxies – and until now, no one knew why.In this episode, host Regina G. Barber talks to Alison Coil, a professor of astronomy and astrophysics at University of California San Diego, about her latest research. They break down what ORCs are, where they come from and what they might reveal about how galaxies evolve over billions of years.Wondering about other happenings across the universe? Email us at shortwave@npr.org – we'd love to hear about it!