John Percy gives an excellent talk about the mysterious "Long Secondary Periods" in Red Giants. If you say you don't know what those periods are, well, watch the video and all will be explained. John is a long time member of the Royal Astronomical Society of Canada - Toronto Centre and a retired professor for the Department of Astronomy and Astrophysics at the University of Toronto. He gave his talk online at the Recreational Astronomy Night hybrid meeting held at the Ontario Science Centre on May 3, 2023.