Tenka (kaika)

Tenka (天火) are a type of atmospheric ghost light told about in various areas of Japan. It is written about in the collection of fantastic stories, the Ehon Hyaku Monogatari from the Edo period and in the essay Kasshi Yawa by Seizan Matsuura and other writings, but it is also told as the folklore of various areas.

In the Atsumi District, Aichi Prefecture, when one's path ahead when on a road at night becomes bright like at noon, it is called a "tenbi" (天火), and in the Ibi District, Gifu Prefecture, the mysterious fires that make a great noise in the evening sky in the summer and fly are called "tenpi" (天火).

In the Higashimatsuura District, Saga Prefecture, the weather would become better once a tenka appears, but the homes that they go in result in someone getting ill, so it is said that they are beaten by a kane and driven out.

In the Tamana District, Kumamoto Prefecture, it is a mysterious fire that would fall from the heavens and has a size about that of a paper lantern, and it is said that a conflagration results when it falls on the roof of a house. In the Saga Prefecture region, they were thought of as a premonition for a conflagration, and were detested.

It is said that tenka were once thought of as a type of vengeful spirit (onryō), and in the document on folk customs "Amakusatō Minzokushi" from the Amakusa islands, Kumamoto Prefecture, there is the following legend. A certain man went to Oniike village (now Amakusa city) to fish, but the villagers treated him as an outsider and treated him ill, and due to that, he died from an illness. From then on, a ball of fire would come flying in Oniike every evening, and it moved on to burn a brush, and without even a chance for the villages to try to extinguish the fire, it spread, and completely burned down the houses of the village. The villagers feared this as the deed of that man's vengeful spirit, and built a jizō at the place where he was ill-treated, and it is said that his spirit is mourned for every winter.

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Wikipedia