"In November of 1974, A small group from SETI, S.E.T.I. (Search for Extraterrestrial Intelligence), Used the radio dishes at Arecibo to send out a message to whoever might be listening. They sent about a quarter of a kilobyte...including: Structure of human DNA, map of our solar system, population of the earth. Helpful facts like that. In January of 1993, Arecibo received a message back. From an extraterrestrial...of unknown source."