The Lonely Death of a Giant Star

A ghostly tombstone lingers deep in intergalactic space

Shockwaves from exploding stars often producing dramatic cosmic bubbles, as seen here. Image credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA) Acknowledgment: J. Hughes (Rutgers University)

Something strange lingers in the vast voids between galaxies. Back in 2019, astronomers Anna Kapinska and Emil Lenc found two ghostly radio signals coming from deep space. Each was circular in shape and glowing faintly in radio frequencies.