19th-century engraving depicting ball lightning, via Wikipedia.
New research supports a 14-year-old theory that could explain how lightning could form itself into a ball that moves eerily in a very un-lightning way until it, sometimes, eventually explodes.
By sheer luck, researchers in China happened to capture images of ball lightning on video and, simultaneously, measured the wavelengths of light coming from the ball on a spectrograph. The resulting data suggests that ball lightning is actually a chemical reaction that begins when lightning vaporizes silicon oxide in dirt. So the glowing orb isn’t lightning, itself, but, rather, a ball of hot gas. In a way, it’s similar to how neon lights work — producing bright, colorful light by running an electric charge through a tube of gas.