Join us for our April meeting, Wednesday, April 23, 7:30 PM at the Grand Canyon Regional Airport conference room. Our speaker will be PWAC member Keith Thorne. Keith, now retired from CalTech, will explain what gravitational waves are, how they can be detected from black holes, neutron stars smashing together, and how LIGO has ushered in a whole new era of astrophysical observation. The meeting will also be available to our members over Zoom, with link to be provide separately.