Scientists reached a new frontier in understanding pulsars, the dense, whirling remains of exploded stars. 💥 The NICER X-ray instrument on the International Space Station produced the 1st dependable measurements of both the mass and size of a pulsar, including a surface map. It turns out these cores of dead stars can be weirder than we thought. NICER was built and is operated out of Goddard. Read more: https://go.nasa.gov/2PIWwlg | NASA’s Goddard Space Flight Center