In November 1974 , a largely symbolic attempt was made at the Arecibo Observatory to send a message to other worlds . Known as the Arecibo Message , it was sent towards the globular cluster M13 , which is 25,000 light-years from Earth . Further IRMs Cosmic Call , Teen Age Message , Cosmic Call 2 , and A Message From Earth were transmitted in 1999 , 2001 , 2003 and 2008 from the Evpatoria Planetary Radar
Teen Age Message
Teen Age Message
Search for extraterrestrial intelligence