Keith Cooper is the editor of Astronomy Now and the NASA-sponsored Astrobiology Magazine. Keith specializes in writing about astrophysics, planetary science, cosmology, and astrobiology, and he has written for New Scientist, Sky & Telescope, Physics World, and Centauri Dreams.
~~tag-text~~
In 1974 a message was beamed towards the stars by the giant Arecibo telescope in Puerto Rico, a brief blast of radio waves designed to alert extraterrestrial civilizations to our existence. Of course, we don't know if such civilizations really exist. But ... SEE MORE