GW170817 (2 of 3) (IMAGE) Northwestern University Caption This is a still image from an animation that captures phenomena observed over the course of nine days following the neutron star merger known as GW170817. Credit NASA Usage Restrictions Credit must be given License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.