The ultimate guide to Project Blue Book by one of the lead astronomers for the US Air Force program to investigate UFO sightings-and featured in History Channel's Project Blue Book.
Bestselling author and father of the Ancient Alien Theory Erich von Daniken explores what drove ancient humans to build city-sized places underground around the world and its connection to conflicts in the sky.
Mainstream SETI scientists and ancient alien theorists don't agree on much, but one opinion they share is that the undisputed authority on the possibility of alien existence was the late Carl Sagan (1934-1996), whose voluminous writings on the subject have had a profound influence on ETI research.
