Both. Clearly, some UFO sightings have been of objects that are physical and unknown. Many (most?) were misidentification and hoaxes. If you're actually aski

Both. Clearly, some UFO sightings have been of objects that are physical and unknown. Many (most?) were misidentification and hoaxes. If you're actually asking whether they're alien spacecraft, well, there's a million dollar prize for anyone who can prove that they are, and it's yet to be successfully claimed: http://www.csicop.org/si/show/fakers_and_innocents_the_one_million_dollar_challenge_and_those_who_try_for http://www.csicop.org/si/show/fakers_and_innocents_the_one_m...