Read More UFO Encounters: Live Science
Crashes in Roswell, New Mexico, and flashing lights over New Jersey — for decades, people around the world have looked up at the skies and reported mysterious unidentified objects (UFOs). But are these sightings signs of alien visitation? And are they truly unexplained? A recent New York Times investigation found that the Pentagon had, for years, funded a program to answer just that question. The program found several reports of aircraft that seemed to travel at high speeds and have no signs of propulsion, the Times reported. While the vast majority of UFO sightings, when investigated, have turned out to be the result of ordinary Earthly phenomena, such as weather balloons, flares or rockets, some still leave experts scratching their heads — and looking to the skies for little green men. From white Tic Tacs to flashing lights, here are some of the most mysterious UFO sightings out there. Fighter pilot encounter The Times investigation highlighted one of the most intriguing UFO sightings, which was captured on video. In 2004, two Navy F/A-18F fighter jets (also called Super Hornet or Hornet) encountered a mysterious flying object near San Diego, The New York Times reported. The object seemed to be traveling at high speeds, was surrounded by a glowing halo and was rotating as it moved. According to audio from the event, one of the fighter pilots exclaimed, "There's a whole fleet of them," the Times reported. One of the Navy pilots who witnessed the bizarre event, Cmdr. David Fravor, recalled that the object looked like "a white Tic Tac, about the same size as a Hornet, 40 feet <12 meters> long with no wings," Fravor told The Washington Post. As his plane approached the UFO, the mysterious object accelerated "faster than I'd ever seen anything in my life," Fravor said. Fravor, for his part, is convinced that the source of the object was extraterrestrial, he told The Washington Post.