Reality rarely conforms to our imaginations. We want to see flying saucers piloted by little green men with jet-black eyes, but reality hits us in the face with a weather balloon and tells us to grow up. Many people claim to have seen UFOs, and are quick to attribute their sightings to intelligent alien life performing some grand, spaceship-dance in the sky without either attacking our planet or making any form of contact with us. A handful of simple explanations explain the vast majority of UFO sightings, and give us hope that if aliens do ever visit our planet, they’ll at least be a bit more direct about it.
Certain types of gas, created when plant matter decomposes, can hover above the ground and become incandescent. These are regularly mistaken for UFOs, which happened very famously in Michigan in 1966. The spate of sightings of multi-coloured circular objects oscillating in the night sky were not picked up by radar, and widely believed (and still believed, by some) to be UFOs. The rational explanation came from Dr. J. Allen Hynek, who came up with the marsh gas explanation after a few days looking around the site. In some cases, sub-clouds of gas break off from the main cloud, which could be interpreted as a mother-ship releasing several drones.
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This seems like an unlikely candidate for a UFO impersonator, but it is potentially the most common. Only the sun and moon are brighter than it, and it sits far enough from us to provide an unusual visual effect. It doesn’t move in relation to anything on the earth, so people often mistakenly believe it is a craft following them. The effect is more likely when Venus is closer to the horizon.
Sprites, clouds and atmospheric anomalies
There is a lot going on in the atmosphere, and many of the natural phenomena can appear to be a UFO. Sprites are flashes of light produced by electric fields high up in the sky. These are stimulated by lighting during a thunderstorm, sparking briefly into existence before disappearing. Some clouds can also form into UFO-like shapes, appearing to hover menacingly above us.
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Research balloons and military experiments
The most famous UFO sighting of all time, at Roswell, New Mexico in 1947, was eventually found to be a data-gathering balloon from Project Mogul. At the height of the cold war, the US was monitoring radiation levels in the atmosphere through fear of Russian nuclear activity, and the UFO spotted in Roswell was simply a runaway balloon. Likewise, military tests of jet aircraft can spawn floods of UFO reports.
This seems like an obvious culprit, but people still regularly mistake meteors (space-rocks) for alien spacecraft. The intense pressure of the upper atmosphere and the speed at which they travel means that meteors emit light. The combination of strange lights and motion leads people to claim they’re UFOs, and this is only compounded by the fact that smaller pieces can break off. This is another explanation for reports of “mother-ships” releasing smaller crafts.
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Some reports of UFOs come from people who monitor the sky using radars. Pulses of radio waves are sent out, and machines measure how they reflect off objects in the sky, providing a real-time picture. These waves can bounce off other objects, such as mountains, and create an echo, which travels extremely quickly and can even zig-zag.
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