UFO. United States

This version can refer to any observation in the contrast of an object on a solid background, both day and night.

Night it can be a light in a dark house, on the technique in a dark room, etc.

Day the color of the sky sometimes merge with the color of the surface of the Earth at the horizon level. While it may seem that the object on this piece, floating in the sky. It is clearly seen, for example, at the marine landscapes. This illusion may occur as in the photos (especially black and white) and by direct observation.