News Physics

Here’s what might spark ghostly will-o’-the-wisps

Jostling microbubbles of air and methane can create tiny lightning zaps, lab tests show

A black and white engraving of a bright light hovering over a swampy creek. Trees overhang the water and two people are shown walking nearby, while a castle looms in the background.

Glowing balls of bluish light have been seen above swamps and cemeteries around the world, as seen in this early 1800s engraving. Swamp will-o’-the-wisps are believed to be the burning of seeping methane gas. But what ignites that gas has been shrouded in mystery.

Grosvenor Prints (CC BY 4.0)

By Laura Allen

Read another version of this article at Science News Explores

Under a midnight moon, Luigi Garlaschelli peered out over graves.