Terrifying encounters at 40,000 feet. Pilot accounts of UFOs taking control of their aircraft. Entire jumbo jets disappearing into thin air. Since the dawn of aviation, pilots have experienced unexplainable events in the sky. Could they have witnessed aliens in our airspace?

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The vast Alaskan wilderness is well known for mysterious disappearances, electromagnetic anomalies, stories of strange creatures, and is a hotspot for UFO sightings. Could Alaska’s many mysteries be due to a presence that is not of this world?

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Ancient Aliens is counting down the world’s top ten mysterious islands, including sites said to be home to giants, remote landmasses that are home to massive megalithic structures, and even islands that disappear into thin air. Could these incredible sites provide evidence of extraterrestrial visitation?

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The Center for the Study of Extra-Terrestrial Intelligence defines a “Close Encounter of The Fifth Kind” as direct human contact and communication with extraterrestrial life. But is this a classification that will only be useful in the distant future, or have such encounters already taken place… and within the highest levels of the U.S. government?

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Ancient Aliens is counting down the world’s top ten mysterious devices, from strange, grooved disks found in a cave in China to an ancient Greek computer to an incredible crystal skull unearthed in Mexico. Might these sensational artifacts provide evidence of extraterrestrial visitation?

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Meteor impacts have significantly altered our world, creating the perfect environment for the rise of humankind and delivering metals essential to the development of an advanced civilization. But could new evidence reveal that celestial objects have been directed to Earth by an alien intelligence?

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The Mutual UFO Network–better known as MUFON–is the world’s leading organization devoted to the scientific investigation of unidentified aerial phenomena and other unexplained encounters. With more than five decades of investigations, could MUFON’s extensive database contain definitive proof of extraterrestrial visitation?

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Ancient Aliens is counting down the world’s top ten pyramid sites, from a valley in Peru with over 250 hidden pyramids to an ancient Greek city with mysterious 4800-year-old ruins to Egypt’s famous Giza Plateau. Could the extraordinary structures that stand at these sites provide evidence of extraterrestrial visitation?

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