For the first time, scientists have directly detected gravitational waves. Gravitational waves are ripples in the fabric of spacetime as predicted by Einstein's theory of general relativity. Even though gravitational waves can carry enormous amounts of energy, they cause only tiny effects on earth such that it took 100 years from prediction to detection. The mergers of stellar-mass black holes approximately 1.3 billion years ago were identified as the source of the gravitational waves. This discovery supports Einstein's theory in the dynamic extreme-gravity regime, demonstrates the existence of binary stellar-mass black hole systems, and opens up a new observation window to the universe.
In this talk I will give a brief introduction to gravitational waves, their sources, and the effect they cause on earth. I will discuss the measurement principle of laser interferometric gravitational wave detectors and the technology that made this observation possible. The second part of the talk concentrates on the detected gravitational waves. The main results of the discovery will be presented and the applied analysis methods will be discussed. I will close with an outlook into the future of gravitational wave astronomy.