The Planet X Hypothesis: The History and Legacy of the Theory that the Solar System has a Hidden Planet Audiobook Libro.fm

Naturally as technological advances and the creation of flying aircraft became realities the sighting of UFOs increased as did the interest in potential contact with aliens While incidents like the one at Roswell led to conspiracies and a craze among those who insisted the government was hiding proof of extraterrestrials existence governments across the world were actually secretly studying UFO sightings by the mid20th century