“Just before neutron stars crash, the highly magnetized, plasma-filled regions around them, called magnetospheres, start to interact strongly. New supercomputer simulations explore the tangled magnetic structures around merging neutron stars. Neutron stars pack more mass than our Sun into a ball about 15 miles (24 kilometers) across, roughly the length of Manhattan Island in New York City. This view of a supercomputer simulation of merging, magnetized neutron stars highlights regions producing the highest-energy light. 2025In the chaotic plasma surrounding the neutron stars, particles transform into radiation and vice versa.