When black holes collide, the energy of the event generates intense gravitational waves. These waves were predicted by Einstein in his theories, but scientists have only recently been able to detect them experimentally. In this SciCafe, Barnard College professor and astronomer Janna Levin shares her scientific research on the first recordings of a gravitational wave from the collision of two black holes 1.3 billion years ago. This lecture took place at the Museum on December 7, 2016. Watch a video version here: https://www.youtube.com/watch?v=CLeQtSR_hrA The SciCafe series is proudly sponsored by Judy and Josh Weston.