For more science and technology videos and documentaries, please subscribe to my channel Science&Technology 4U\r<br>\r<br>An unidentified flying object, or UFO, in its most general definition, is any apparent anomaly in the sky that is not identifiable as a known object or phenomenon.\r<br>\r<br>Documentary,2015, Full Documentary, New Documentary, Top Documentaries, Documentaries,HD,2015, documentary films,documentary,\r<br>\r<br>An unidentified flying object, or UFO, in its most general definition, is any apparent anomaly in the sky that is not identifiable as a known object or phenomenon.
