Black Holes Ringing in Space (IMAGE) International Astronomical Union Caption This is the LIGO signal that heralded the era of gravitational wave astronomy. Credit Caltech/MIT/LIGO Lab 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.