A launch mishap led to the best experimental confirmation of gravitational redshift. Get a free audiobook with a 30-day trial of Audible: http://audible.com/VERITASIUM or text VERITASIUM to 500500 Huge thanks to Dr. Pacome Delva: https://ve42.co/pacome Dr. Sven Herrmann: https://ve42.co/sven Gravitational Redshift Test Using Eccentric Galileo Satellites: https://ve42.co/GRtest Disclaimer: It is arguable what is THE best test of general relativity because there are different ways to test the theory. This is the best confirmation of gravitational redshift, which is one of the three original tests proposed by Einstein. Special thanks to Patreon supporters: Donal Botkin, James M Nicholson, Michael Krugman, Nathan Hansen, Ron Neal, Stan Presolski, Terrance Shepherd Animations and editing by Alan Chamberlain Music from http://epidemicsound.com/ "Subtle Substitutes 2" "A sound Foundation 1" "Cell Research 1" "Particle Attraction 1"