Our magnificent gravitational wave astronomers have done it again, adding to the detection collection a new collision between two neutron stars. On 25 April 2019, the LIGO interferometer detected two neutron stars around 520 million light-years away coming together and merging into a single object. It's called GW190425, and although it's only the second such collision astronomers have ever seen, it's already broadening our understanding of these colossal cosmic smash-ups.