"Extraterrestrial life (from the Latin words: extra ("beyond", or "not of") and terrestris ("of or belonging to Earth")) is defined as life that does not originate from Earth. Referred to as alien life, or simply aliens, these hypothetical forms of life range from simple bacteria-like organisms to beings far more advanced than humans." 
"The development and testing of theories about extraterrestrial life is known as exobiology or astrobiology; the term astrobiology, however, includes the study of life on Earth, viewed in its astronomical context. Many prominent scientists consider extraterrestrial life to be plausible, but no direct evidence has yet been found." 
Or, so they think. Approximately how much evidence does it take to convince anyone that this is real and actually happening? I certainly would not depend upon main stream science to present me with "the say so." Most people in that community dare not say anything about this subject, for fear of ruining their career. The fact is, we humans have already made contact with extra terrestrials beings in the past and present.
Numerous people yearly report strange lights performing impossible maneuvers that traditional aircraft, commercial, military, or otherwise, could never execute. And, just as many reports of abduction by alien beings. Of course, that is just the few that were reported. It is speculated there are still many more sightings and abductions that go unreported every year.
The following UFO documentary sums up the subject in a quick and entertaining style. It pulls from the latest and best news clips and various documentaries.
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