The term UFO has become a catch-all for any unidentifiable aerial phenomenon. Floating lights in the sky, strange readings on aircraft radars, and supposed sightings of little green men on the side of the road. How long have humans been seeing things in the sky? You'll learn about the time the ...

The U.S. government, once openly dismissive of UFO sightings that for decades sparked the popular imagination, is poised to issue an expansive account of what it calls "unidentified aerial phenomena," based heavily on observations by American military pilots. The experience of retired U.S. Navy ...