The 2021 Shaw Prize in Astronomy is awarded in equal parts to Victoria Kaspi and Chryssa Kouveliotou for their contributions to the understanding of magnetars, a class of highly magnetized neutron stars that are linked to a wide range of spectacular, transient astrophysical phenomena. By developing new and precise observational techniques, they confirmed the existence of this new class of neutron stars with ultra-strong magnetic fields, and characterized their physical properties. Their work has established magnetars as a new and important class of astrophysical objects.
Neutron stars are ultra-compact remnants of explosions of massive stars, which have exhausted their “fuel” for generating energy through fusion, and then collapse under their own gravity. Most young neutron stars are rapidly rotating with periods of milliseconds to seconds, and many of them emit powerful beams of electromagnetic radiation (observed as pulsars). As such, they are accurate “cosmic clocks” that enable tests of fundamental physics in the presence of a gravitational field many billion times stronger than that on earth. The Nobel Prize in Physics was awarded twice for work on pulsars, in 1974 and in 1993.