As most credible UFOlogists readily admit, proving that extraterrestrial spacecraft have visited our planet is a maddeningly difficult chore.
“The hassle over the word 'proof' boils down to one question: What constitutes proof?” Edward J. Ruppelt, who headed the U.S Air Force’s secret investigation of UFOs in the early 1950s, once wrote. “Does a UFO have to land at the River Entrance to the Pentagon, near the Joint Chiefs of Staff offices? Or is it proof when a ground radar station detects a UFO, sends a jet to intercept it, the jet pilot sees it, and locks on with his radar, only to have the UFO streak away at a phenomenal speed? Is it proof when a jet pilot fires at a UFO and sticks to his story even under the threat of court-martial? Does this constitute proof?”
More recently, Investigative journalist Leslie Keen, author of the 2011 book “UFOs: Generals, Pilots and Government Officials Go on the Record,” has noted that in roughly 90 to 95 percent of UFO sightings, observers turn out actually to have seen weather balloons, ball lightning, flares, aircraft, and other mundane phenomena. But another five to 10 percent of sightings are not so easily explainable, but that’s not the same as demonstrating that they are extraterrestrial in origin. Nevertheless, she argues, the hypothesis that UFOs are visitors from other worlds “is a rational one, and must be taken into account, given the data that we have.”
Here is some of the most compelling reasons that UFOs may be more than simple misidentifications of natural phenomena or terrestrial aircraft:
• The long, documented history of sightings. UFOs were around, in fact, long before humans themselves took to the air. The first account of a UFO sighting in America was back in 1639, when Massachusetts colony governor John Winthrop noted in his journal that one James Everell, “a sober, discreet man,” and two other witnesses watched a luminous object fly up and down the Muddy River near Charlestown for two to three hours. There are documented sightings of what were then called “airships” during the 1800s as well, such as the July 1884 sighting of a Saturn-shaped UFO (a ball surrounded by a ring) in Norwood, NY, and a fast-moving object that briefly hovered over the startled townspeople of Everest, KS in 1897.
• Numerous modern sightings by credible, well-trained professional observers. In Ruppelt’s 1955 book , “The Report on Unidentified Flying Objects,” he documented numerous instances of military service members, military and civilian pilots, scientists and other credible professionals who had observed UFOs. In one instance, Ruppelt describes the experience of a pilot of an Air Force F-86 fighter jet, who was scrambled to track a UFO and got to within 1,000 yards of a saucer-shaped object that abruptly flew away from him in a burst of speed after he fired upon it. He also mentions a 1948 UFO encounter in which two airline pilots got to within 700 feet of a UFO and saw two rows of windows with bright lights.
• Consistencies in the descriptions of purported alien ships. Over the decades, witnesses who’ve seen UFOs have shown remarkable consistency in the shapes and other characteristics of the objects they’ve described. In 1949, the authors of the report for Project Sign, one of the early military investigations of UFOs, identified four main groups of objects—flying disks or saucers, cigar or torpedo-shaped craft without wings or fins, spherical or balloon-shaped objects that were capable of hovering or flying at high speed, and balls of light with no apparent physical form that were similarly maneuverable. Nearly a quarter-century later, a French government investigation headed by Claude Poher of the National Center for Space Research found similar patterns in more than 1,000 reports from France and various countries. One caveat is that in recent years, reports of wedge-shaped UFOs—which bear a similarity to the latest terrestrial military aircraft—have begun to supplant some of the traditional shapes.
• Possible physical evidence of encounters with alien spacecraft. The 1968 University of Colorado report, compiled by a team headed by James Condon, documented numerous instances of areas where soil, grass, and other vegetation had been claimed by witnesses to have been flattened, burned, broken off, or blown away by a UFO. A report by Stanford University astrophysicist Peter Sturrock, who led a scientific study of physical evidence of UFOs in the late 1990s, describes samples of plants taken from a purported UFO landing site in France in 1981. French researchers found that the leaves had undergone unusual chemical changes of the sort that could have been caused by powerful microwave radiation—which was even more difficult to explain, considering that they found no trace of radioactivity at the site.
• Physiological effects on UFO witnesses. The Sturrock report describes in detail various symptoms reported by individuals who had encountered UFOS, ranging from burns and temporary deafness to persistent nausea and memory loss. Among the most vivid examples: Betty Cash, Vickie Landrum and Landrum’s young grandson Colby, who reportedly happened upon a “large, diamond-shaped object” hovering over a Texas road in December 1980. All three became ill afterward; Cash, for example, developed large water blisters on her face and swelling that closed her eyes, in addition to severe nausea and diarrhea. The effects persisted for years, and she was hospitalized more than two dozen times.