A new window to the cosmos is open, now that the Laser Interferometer Gravitational-Wave Observatory (LIGO) Scientific Collaboration has detected Einstein’s long-predicted gravitational waves. LIGO’s detectors, based in Washington state and Louisiana, will soon be joined by another instrument trying to net these elusive ripples in space-time. Experts hope to start test operations this year at Japan’s Kamioka Gravitational Wave Detector (KAGRA); observational data is expected by March 2018.