50 Years Ago Physics 50 years ago, physicists found the speed of light Excerpt from the December 2, 1972 issue of Science News In the 1970s, scientists measured the speed of light: 299,792.456 kilometers per second, or 299,792,456 meters per second. Fifty years later, they continue putting light through its paces. Eduard Muzhevskyi/Science Photo Library/Getty Share this:EmailFacebookTwitterPinterestPocketRedditPrint By Nikk Ogasa December 9, 2022 at 7:00 am A New Figure for the Cosmic Speed Limit – Science News, December 2, 1972 A group at the National Bureau of Standards at Boulder, Colo.,