An unidentified flying object, or UFO, is any real or apparent flying object which cannot be identified by the observer and which remains unidentified after investigation. The shape of a UFO can vary between a defined shape (sphere, equilateral triangle, or diamond shaped) and an undefined shape (black mass, moving lights). Through the study of UFO's (called Ufology), various methods have been created to categorize the sightings.

An unidentified flying object, or UFO, is any real or apparent flying object which cannot be identif...

Throughout history there have been numerous sightings of UFO's. In fact the ancient Hindu Ramayana d...

There are multiple theories about the existence of extra-terrestrials. The two main theories are cal...