S02E22: What Is A Light Cone? May 20, 2019Season 2cone, light, observable, universepat Darren McKee, host of The Reality Check, has many questions. This episode he asks: “What is a light cone?” If you have feedback or a topic suggestion, email us. Download direct: mp3 file http://traffic.libsyn.com/astronomyin5/S02E22.mp3