You are working for SETI, the Search for Extraterrestrial Intelligence. One day, you receive a radio communication from an alien intelligence. Although you cannot understand their language, they have included some photos from an I Love Lucy episode. The photos allow you to determine that it is the episode in which Lucy makes a television commercial on Vitameatavegamin. This episode first aired on CBS on May 5, 1952. Before running to your supervisor to tell him the news, you quickly determine how far away in light-years the alien civilization is.
