Nergis Mavalvala spoke to a packed house on October 10, 2018, about the historic underpinnings, recent findings, and future goals of the Laser Interferometer Gravitational-Wave Observatory (LIGO) project. Using a multimedia presentation, Dr. Mavalvala described how the LIGO instruments are able to map the collision of high-mass objects like black holes and neutron stars. For black holes, which emit no light, these measurements mark the first opportunity to collect observations confirming predictions made by Einstein about how gravity would be affected by these collisions. A recording across multiple LIGO sites of the collision of neutron stars enabled astronomers to focus their telescopes on a narrow part of the sky, thereby creating a rare record of the elements—including gold—generated during the supernova event. The talk was a great illustration of how science and engineering build on each other, and how pure research can promote a sense of wonder about our universe, and can motivate technological advances that may lead to decades of work in applied science and engineering.