Donald Edward Keyhoe was an American Marine Corps naval aviator, writer of aviation articles and stories in a variety of publications, and tour manager of aviation pioneer Charles Lindbergh.

An unidentified flying object (UFO), or unidentified anomalous phenomenon (UAP), is any perceived airborne, submerged or transmedium phenomenon that cannot be immediately identified or explained. Upon investigation, most UAPs are identified as known objects or atmospheric phenomena, while a small number remain unexplained.