Gravitational Wave Astronomy: We can hear the dark universe! (Karsten Danzmann)

We have been looking at the universe with our eyes for thousands of years. But over 99% of the universe is dark and will never be observed with electromagnetic waves. Since September 14, 2015, everything has changed: gravitational waves have been discovered! We have been given a new sense organ and can finally hear the dark side of the universe. The first sounds we heard came from completely unexpectedly heavy black holes. Gravitational waves have now become a new kind of astronomy. Hundreds of such events are now recorded almost daily, with frequencies ranging from a few hertz to a few kHz. And in 2035 we will also be able to observe the low-frequency sources with LISA, an observatory in the mHz range. Nobody knows what other dark secrets are still waiting for us out there.