As a dying star’s iron core shrinks to some 20 km in diameter and its spin increases by a factor of 10 000, it collapses in a supernova and forms a neutron star. Before the neutron star reaches its solid equilibrium state, the stellar material acts as a dense dynamo powered by superconducting, spinning, and convective fluid. If the spin speed is faster than the convection, the magnetic field strength can reach 1014–1015 gauss—the strongest yet found in the universe—and the neutron star is then classified as a magnetar (see Physics Today, May 2005, page 19). When a magnetar forms, a fraction of its spin energy can be emitted later as optical radiation and produce what’s known as a superluminous supernova.
Ke-Jung Chen of the Academia Sinica Institute of Astronomy and Astrophysics in Taipei, Taiwan, and his colleagues recently published results of a three-dimensional hydrodynamical...
