Interactive Map: UFO Sightings Taken Seriously by the U.S. Government

Mysterious lights. Sinister saucers. Alien abductions. Between 1947 and 1969, at the height of the Cold War, more than 12,000 UFO sightings were reported to Project Blue Book, a small, top-secret Air Force team. Their mission? To scientifically investigate the incidents and determine whether any posed a national security threat. Here are some of their most fascinating cases, along with other seminal UFO sightings.