Early history

Unexplained aerial observations have been reported throughout history. Some were undoubtedly astronomical in nature: comets, bright meteors, one or more of the five planets that can be seen with the naked eye, planetary conjunctions, or atmospheric optical phenomena such as parhelia and lenticular clouds. An example is Halley's Comet, which was recorded first by Chinese astronomers in 240 BC and possibly as early as 467 BC. Such sightings throughout history often were treated as supernatural portents, angels, or other religious omens. Some current-day UFO researchers have noticed similarities between some religious symbols in medieval paintings and UFO reports^[19] though the canonical and symbolic character of such images is documented by art historians placing more conventional religious interpretations on such images.^[20]

• On January 25, 1878, the Denison Daily News noted that John Martin, a local farmer, had reported seeing a large, dark, circular object resembling a balloon flying "at wonderful speed." Martin, according to the newspaper account, said it appeared to be about the size of a saucer, the first known use of the word "saucer" in association with a UFO.^[21]
• In April 1897 thousands of people reported seeing "airships" in various parts of the United States. Many signed affidavits. Scores of people even reported talking to the pilots. Thomas Edison was asked his opinion, and said, "You can take it from me that it is a pure fake."^[22][23]
• On February 28, 1904, there was a sighting by three crew members on the USS Supply 300 miles (483 km) west of San Francisco, reported by Lieutenant Frank Schofield, later to become Commander-in-Chief of the Pacific Battle Fleet. Schofield wrote of three bright red egg-shaped and circular objects flying in echelon formation that approached beneath the cloud layer, then changed course and "soared" above the clouds, departing directly away from the earth after two to three minutes. The largest had an apparent size of about six Suns, he said.^[24][25]
• The three earliest known pilot UFO sightings, of 1,305 similar sitings cataloged by NARCAP, took place in 1916 and 1926. On January 31, 1916, a UK pilot near Rochford reported a row of lights, resembling lighted windows on a railway carriage, that rose and disappeared. In January 1926 a pilot reported six "flying manhole covers" between Wichita, Kansas, and Colorado Springs, Colorado. In late September 1926 an airmail pilot over Nevada said he had been forced to land by a huge, wingless, cylindrical object.^[26]
• On August 5, 1926, while traveling in the Humboldt Mountains of Tibet's Kokonor region, Russian explorer Nicholas Roerich reported, members of his expedition saw "something big and shiny reflecting the sun, like a huge oval moving at great speed. Crossing our camp the thing changed in its direction from south to southwest. And we saw how it disappeared in the intense blue sky. We even had time to take our field glasses and saw quite distinctly an oval form with shiny surface, one side of which was brilliant from the sun."^[27] Another description by Roerich was of a "shiny body flying from north to south. Field glasses are at hand. It is a huge body. One side glows in the sun. It is oval in shape. Then it somehow turns in another direction and disappears in the southwest."^[28]
• In the Pacific and European theatres during World War II, "foo-fighters" (metallic spheres, balls of light and other shapes that followed aircraft) were reported and on occasion photographed by Allied and Axis pilots. Some proposed Allied explanations at the time included St. Elmo's fire, the planet Venus, hallucinations from oxygen deprivation, or German secret weapons.^[29][30]
• In 1946 more than 2,000 reports were collected, primarily by the Swedish military, of unidentified aerial objects over the Scandinavian nations, along with isolated reports from France, Portugal, Italy and Greece. The objects were referred to as "Russian hail" and later as "ghost rockets" because it was thought that the mysterious objects were possibly Russian tests of captured German V1 or V2 rockets. Although most were thought to be such natural phenomena as meteors, more than 200 were tracked on radar by the Swedish military and deemed to be "real physical objects." In a 1948 top secret document, Swedish authorities advised the USAF Europe that some of their investigators believed these craft to be extraterrestrial in origin.^[