The UFO phenomenon is one that can be linked to many other phenomenon. The Ancient Astronaut theory documents many sightings of similiar unidentified flying objects throughout history.
According to ancient astronaut theories, intelligent extraterrestrial beings (called ancient astronauts or ancient aliens) have visited Earth and this contact is connected with the origins or development of human cultures, technologies, and/or religions.
Some of these theories propose that deities from most—if not all—religions are actually extraterrestrials, and their technologies were taken as evidence of their divine status. ~en.wikipedia.org
Given the nature of many present day UFO sightings and ‘abductions’ is it reasonable to assume that the visions and sightings of angels, gods, and demons may be one in the same phenomenon?
Edmund Halley was a brilliant English astronomer whose mathematical calculations pinpointed the return of the comet that bears his name. Halley was fascinated by the earth’s magnetic field. He noticed the direction of the field varied slightly over time and the only way he could account for this was there existed not one, but several, magnetic fields. Halley came to believe that the Earth was hollow and within it was a second sphere with another field. In fact, to account for all the variations in the field, Halley finally proposed that the Earth was composed of some four spheres, each nestled inside another.