The observation of gravitational waves (see Fig. 1) in the Laser Interferometer Gravitational-wave Observatory (LIGO) was announced on 11 February 2016 (Abbott et al., 2016a), 100 years after Einstein proposed the existence of gravitational waves (Einstein, 1916, 1918). This observation came after more than 50 years of experimental efforts to develop sensitive enough detectors to observe the tiny distortions in spacetime from gravitational waves. The Nobel Prize for 2017 was awarded to Rainer (“Rai”) Weiss, Kip Thorne and myself for decisive contributions to the LIGO detector and the observation of gravitational waves. In fact, the success of LIGO follows from decades of R&D on the concept and techniques, which were covered in Rai Weiss’ Nobel Lecture, followed by the design, construction and evolving the LIGO large-scale interferometers to be more and more sensitive to gravitational waves. This work has been carried through the LIGO Laboratory and the scientific exploitation through the LIGO Scientific Collaboration, having more than 1000 scientists, who author the gravitational wave observational papers. In addition, many others made important contributions to the science of black holes, numerical relativity, etc
