Atmospheric ghost lights are lights (or fires) that appear in the atmosphere without an obvious cause. Examples include the onibi, hitodama and will-o'-wisp. They are often seen in humid climates.[1]
According to legend, some lights are wandering spirits of the dead, the work of devils or yōkai, or the pranks of fairies. They are feared by some people as a portent of death. In other parts of the world, there are folk beliefs that supernatural fires appear where treasure is buried; these fires are said to be the spirits of the treasure or the spirits of humans buried with grave goods.[1] Atmospheric ghost lights are also sometimes thought to be related to UFOs.[2]
Some ghost lights such as St. Elmo's fire or the shiranui have been explained as optical phenomena of light emitted through electrical activity. Other types may be due to combustion of flammable gases, ball lightning, meteors, torches and other human-made fires, the misperception of human objects, and pranks.[2][3]