Using the X-ray data from NASA’s Neutron star Interior Composition Explorer (NICER), astronomers have produced a map of hot spots on the surface of a pulsar called PSR J0030+0451, a millisecond pulsar located approximately 1,174 light-years away in the constellation of Pisces, and obtained very precise measurements of a pulsar’s size and mass. “In the simplest model, a pulsar has a powerful magnetic field shaped much like a household bar magnet,”...
