There are reports where people who were once near death have recounted various mystical experiences. Some report going into a tunnel and emerging in a light, others recall being reunited with loved ones, a sense of peace and so on. This may suggest that there is an existence beyond the grave. While such experiences are profound, no one has returned with proof.
Some skeptics suggest that the experiences are explainable as natural and predictable hallucinations of a traumatized brain. A study of people in cardiac arrest in 2015 found that when the heart is dying, it gets peppered by signals from the brain, which tries to remain active. These signals might be responsible for near-death experiences, researchers figure.
2. Bigfoot
A large, hairy manlike beast, called Bigfoot, has long been reported by eyewitnesses across America. Still, not a single body has been found and not one has been killed by a hunter or struck by a speeding car, or died of natural causes.
In the absence of hard evidence (such as bones, or teeth), support purely comes down to eyewitness sightings and ambiguous photos and films. Science will never be able to prove that creatures like Bigfoot and the Loch Ness monster do not exist, and perhaps it may be possible that these mysterious beasts lurk far from prying eyes.
4. Mysterious Disappearances
There are various reasons why people disappear. Most of the time it is due to runaways or an accident, and a few are abducted or killed, but most are eventually found. Yet some cases of disappearance are truly mysterious. From the crew of the Marie Celeste, to Jimmy Hoffa, as well as Amelia Earhart and Natalee Holloway, some people seem to have vanished without a trace.
Usually, when missing persons are found, it is due to the work of the police, a confession, or an accident. But when the evidence of a disappearance is lacking and leads are lost, forensic science can't always solve the crime.
Spirits of the dead have long made an appearance in our culture and folklore. There have also been reports of both shadowy strangers as well as departed loved ones. Definite proof for the existence of ghosts still remains elusive. Yet sincere eyewitnesses continue to report seeing, photographing and even communicating with ghosts. Perhaps one day we will discover an answer to the mystery.
6. Deja vu
This French phrase means, 'already seen', referring to the distinct, puzzling and mysterious feeling of having experienced a specific set of circumstances before. Take the following as an example: a woman might walk into a building in a foreign country she's never visited, and sense that the setting is familiar.
Some people attribute deja vu to psychic experiences or unbidden glimpses of previous lives. Perhaps research into human psychology can offer more naturalistic explanations, but ultimately the cause and nature of the phenomenon itself remain a mystery.
There is no doubt that UFOs exist - many people see things in the skies that they cannot identify - from aircraft to meteors. But, whether or not these objects and lights belong to an alien spacecraft is another matter. The distance and effort involved in getting to Earth may make such a situation seem unlikely. However, careful investigation has revealed known causes for most sighting reports. Nevertheless, some UFO incidents also remain unexplained.
8. The Taos Hum
Some residents in the small city of Taos, New Mexico have been puzzled for years by a mysterious and faint low-frequency hum in the desert air. Strangely enough, only about 2 percent of Taos residents report hearing the sound.
For some, it is believed that it is caused by unusual acoustics, others suspect mass hysteria or some secret, sinister purpose. Whatever it may be - be it a hum, buzz, or psychological, natural or supernatural, the sound's origin has yet to be located.