Of course, some people believe not only in alien planets, but in technologically-advanced alien civilizations capable of exploring other worlds. Indeed, they might point toward the trove of visual “evidence” apparently depicting encounters with extraterrestrial visitors on Earth. These alleged proofs mushroomed with the advent of modern media such as photography, video and the world wide web.
\The Roswell incident is one of the earliest and most famous supposed UFO encounters. Indeed, it has long cited by ufologists as an example of a coverup by the U.S. government. However, the curious object which allegedly crashed near Roswell, New Mexico, in 1947 is claimed by the military to have been a surveillance balloon, not an alien spacecraft.
Likewise, the U.S. Air Force site referred to as Area 51 has sparked considerable conjecture over the years. Many ufologists claim that it houses evidence of extraterrestrial technology, including a crashed spacecraft. The government itself has revealed little about the purpose of the facility, but it is likely used for developing experimental weapons and aircraft.