Kilonova-Artist Impression (IMAGE) George Washington University Caption This artist's impression shows two tiny but very dense neutron stars at the point at which they merge and explode as a kilonova. Such a very rare event is expected to produce both gravitational waves and a short gamma-ray burst, both of which were observed on Aug. 17, 2017 by LIGO-Virgo and Fermi/INTEGRAL respectively. Credit ESO/L. Calçada/M. Kornmesser Usage Restrictions None 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.