UFO or unidentified flying objects is the name used for the space ship used by the aliens to move in the solar system. It's been shown in so many movies, as well as pictures but still a question that always arises is the existence of the aliens. But till date there is no such evidence or proof found on their existence. There have been so many incidences where people are found admitting of seeing a saucer shaped object flying in the air. In one incident a farmer named John Martin on 25th January 1878 was found admitting of seeing a circular flying object which was dark and large was moving at a very high speed. Secondly about 2000 unidentified aircrafts were seen in the Scandinavian nations in 1946. In addition to this more reports were received from Italy, France, Portugal and Greece which were later referred to as ghost rockets. And the radars used by the Swedish military confirmed the existence of more than 200 of the UFO's as physical objects present in the sky.
Getting towards more controversial part of the question is the area 51. Area 51 is an alternate name which is given to a military base located in west part of United States. It is one of the most secret places in the world. It is believed that there are many scientists researching on a UFO that landed on earth few years ago. Moreover it is also said there are 2 - 3 bodies of aliens are kept that are used for experimentation and research work. In addition to this a scientist accepted the existence of UFO as well as the research work in area 51. Even the movie Men in Black starring will smith was based on the controversy related to area 51. All the incidents mentioned above prove the existence of UFO's to some extent if not fully.
