Two neutron stars. One is 50% more massive than the other, yet they are almost exactly the same size. The results have big implications for understanding what neutron stars are really made of.
In 2019 a team of astronomers led by Thomas Riley, a postdoctoral researcher, and Anna Watts, a professor of astrophysics at the
University of Amsterdam, measured the mass and radius of a certain neutron star. The neutron star in question was
J0030+0451 (or J0030 for short). They found it to be about 1.4 times the mass of the sun and about 16 miles across – pretty typical for neutron stars.