Like a scene from 'Avatar,' some forests glow in the dark via 'foxfire'! Learn more

Around the world forests glow in the dark at night. They are lit up by what’s called “foxfire,” sometimes referred to as “fairy fire.” It isn’t fire at all, though. This puzzled thinkers throughout history, including Aristotle who wrote the oldest recorded documentation of it in 382 B.C. He wrote of a light that, unlike fire, was cold to the touch.

There were many more documentations of the strange glow throughout history, but it wasn’t until 1823 that the cause was finally discovered. The glow emitted from wooden support beams in mines was examined, and it was found that the luminescence came from fungal growth.

The name foxfire comes from one of two places. Either it has to do with the association of foxes with fire, or the “fox” in foxfire derives from an Old French word meaning “false.” Although generally very dim, in some cases foxfire is bright enough to read by.

Foxfire is sometimes referred to in popular culture. The most famous of these might be the novel Adventures of Huckleberry Finn by Mark Twain, where the characters Huckleberry Finn and Tom Sawyer use foxfire as a source of light in order to dig a tunnel.

(Source)