unidentified flying object (UFO)

Aerial object or optical phenomenon not readily explainable to the observer. Interest in UFOs increased with developments in aeronautics and astronautics after World War II. A U.S. government panel investigating sightings in the 1950s reported that 90percnt coincided with astronomical or meteorological phenomena or sightings of aircraft, birds, or hot gases, sometimes under unusual weather conditions. Some remained unexplained, however, and in the mid 1960s a few scientists concluded that a small percentage indicated the presence of extraterrestrial visitors. This sensational hypothesis, promoted in the press, met with prompt resistance from other scientists. A U.S. Air Force UFO study begun in 1968 firmly rejected the extraterrestrial hypothesis, but a large fraction of the public, and a few scientists, continued to support it. UFO reports vary widely in reliability. The unaided eye is easily fooled; radar sightings of UFOs, more reliable in some ways, may fail to distinguish physical objects from meteor trails, rain, or thermal discontinuities and are subject to radio interference. Seealso SETI.

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A saucer is a small type of dishware specifically for use with and for supporting a cup - a cylindrical cup intended for coffee or a half-sphere teacup for tea. Additionally, the saucer is a distant cousin to the plate. The saucer has a raised center with a depression sized to fit a mating cup. Saucers were originally used to cool the contents of the cup; the hot liquid was poured into the saucer, with the wider surface area cooling the liquid rapidly. No longer used for this purpose, the saucer is useful to protect surfaces from possible damage due to the heat of a cup, and to catch overflow, splashes, and drips from the cup, so protecting both table linen and the user sitting in a free standing chair who holds both cup and saucer. The saucer also provides a convenient place to place a damp spoon, as might be used to stir the drink in the cup in order to mix sweeteners or creamers into tea or coffee. Not only are saucers used by humans, they are also used by animals, e.g. cats may drink or eat from saucers.

Although often part of a place setting in a dinner set, teacups with unique styling are often sold with matching saucers, sometimes alone, or as part of a tea set, including a teapot and small dessert plates. A set of four is typical for a tea set. See also demitasse.