flying saucersaka Tman/Flickr

Summer is officially here, which means UFO sightings are bound to spike until late September, as they have for roughly the last 65 years.

In honor of the summer ritual, Tech Insider dug through the mountain of CIA documentsrelated to UFO sightings, which the agency declassified nearly 40 years ago. Many of the sighting reports date back to the early 1950s, at a time when political tensions were high and flying objects were seen as national security threats.

Here are some of the most interesting.

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