Of the many astronomical observatories in the United States and abroad, none has ever photographed an object that remotely resembled a spaceship. Since 1957, hundreds of members of Moonwatch teams throughout the world have watched the skies to record passages of the many artificial satellites, but no Moonwatch team has yet reported the presence of a spaceship. Radar stations on all continents keep track of every artificial satellite and fragment of satellite orbiting the earth. In February 1963 there were 284 such objects, originating in Canada, Great Britain, Russia, and the United States. If an interloper from beyond our planet should join the parade, Space Track stations would at once detect its presence. The Air Force has found no evidence of any kind that anyone has ever seen, heard, smelled, photographed, touched, or in any way detected a trace of an interplanetary spacecraft. Extraterrestrial visitors have not yet arrived, and may never arrive. If and when they do, our Air Force wants to be the first to know. The Air Force will continue to investigate reports of unidentified flying objects and to treat them as “serious business.”[XIII-14] The security of the nation depends on this watchfulness. When a pilot sees a bright object flashing through the sky and cannot immediately recognize it, he knows that he may be looking at a meteor, a balloon, a bird, a sundog, a planetary mirage, or another plane. On the other hand, since he may be catching a significant glimpse of a guided missile or an aircraft from beyond the United States, he promptly reports another UFO. The Air Force cannot afford to guess what is in our skies. They want to _know_. The creative scientist, eternally curious, keeps an open mind toward strange phenomena and novel ideas, knowing that we have only begun to understand the universe we live in. He remembers, too, that Biot’s discovery that meteorites were “stones from the sky” was at first greeted with disbelief, and he hopes never to be guilty of similar obtuseness. But an open mind does not mean credulity or a suspension of the logical faculties that are man’s most valuable asset. Human beings now stand on the threshold of space. Visits to and from other worlds may occur in the future, bringing new facts and new interpretations of reality that we cannot now imagine. No evidence yet found indicates that such visits have begun. No fact so far determined suggests that a single unidentified flying object has originated outside our own planet. [XIII-1] Keyhoe, D. E. _The Flying Saucer Conspiracy._ New York: Henry Holt & Co., 1955. [XIII-1a] Tacker, L. J. _Flying Saucers and the U. S. Air Force._ Princeton, N.J.: D. Van Nostrand Co., 1960. [XIII-2] Keyhoe, D. E. _Flying Saucers from Outer Space._ New York: Henry Holt & Co., 1953. [XIII-3] _UFO Investigator_ (March 1960). [XIII-4] _UFO Investigator_ (August-September 1958). [XIII-5] _UFO Investigator_ (April-May 1961).