Jacques Vallée
From RationalWiki
Jacques Fabrice Vallée (born 1939) is a former astronomer and computer scientist turned venture capitalist and ufologist. He's notable for rejecting the "extraterrestrial hypothesis", i.e. the claim that UFOs are alien spacecraft, and advocating a "multidimensional visitation hypothesis".
He thinks that crop circles are caused by weapon tests conducted by the terrestrial military, or at least has written an article claiming that.