Starquakes: The Birth of Cosmic Radio Signals ⚡ экспресс
For the first time, coupled modeling of magneto-elastic dynamics of the magnetar crust and three-dimensional relativistic resistive force-free electrodynamics of the magnetosphere has been performed. Surface motions launch fast magnetosonic and Alfvén waves, which rapidly reach a nonlinear regime, generating giant shock waves, relativistic blast waves, trapped Alfvén waves, nonlinear Alfvén ejections, and transient equatorial current sheets interacting with waves. After the initial nonlinear phase, the magnetosphere partially 'combs out' and adopts a configuration close to a strongly disturbed split monopole. The results impose strict constraints on energy conversion efficiency, which can narrow down models of fast radio bursts, especially for hyperactive repeating sources, and also indicate the possibility of quasi-periodic imprints of elastic crustal oscillations on magnetospheric waves.
Magnetars are a rare type of neutron stars, the remnants of massive stellar deaths. Their magnetic fields are billions of times stronger than Earth's magnets. The thin crust of such a star occasionally cracks, triggering a cascade: the field, like a taut string, vibrates, accelerating trapped particles to light speed. In hundredths of a second, as much energy is released as the Sun emits in hundreds of thousands of years. We detect this as a fast radio burst — a mysterious signal from deep space.
The new model for the first time linked crustal quakes to the magnetic field's response. It turned out that repeated shudders create a rhythmic pattern of bursts, reminiscent of signals from pulsars — stellar lighthouses discovered by Jocelyn Bell Burnell in 1967. Magnetars themselves are a legacy of predictions by Fritz Zwicky in the 1930s.
The dance of starquakes unveils the nature of the most powerful radio bursts in the universe.
🎯 A magnetar's magnetic field is billions of times stronger than Earth's. If it were at the Moon's distance, not just cards but any magnetic recording would fly.
🎬 In Carl Sagan's 'Contact,' the alien signal turned out to be a message; fast radio bursts were also initially mistaken for greetings from extraterrestrial civilizations.