Joshua Pritchard

Astronomers caught a signal from a cosmic lighthouse — a radio pulsar with a period of 36 minutes. Unlike ordinary pulsars (neutron stars that spin hundreds of times per second), this one barely turned. It transmitted pulses for only eight days and vanished, visible only in the radio range.

In 2022, astronomers began discovering strange cosmic beacons — long-period radio transients. Unlike fast pulsars, discovered by Jocelyn Bell Burnell in 1967, these objects flared with periods of tens of minutes and hours.

At the heart of nearly every large galaxy sits a supermassive black hole. Usually it behaves quietly, but sometimes, like a waking volcano, it spits out narrow plasma jets. These jets glow in the radio band, making the galaxy 'radio-loud.' Astronomers have long known this happens, but they couldn't catch the very moment of switching on.