The phenomenon in which a glowing sphere appears near the ground during or after lightning is called ball lightning.
Ball lightning is described as a luminous sphere or globe that may appear during thunderstorms, often close to the ground. Reported sizes range from a few centimeters to several meters, and observers have described red, orange, yellow, white, and blue colors. Unlike an ordinary lightning flash, which lasts a fraction of a second, ball lightning reports often describe objects that persist for seconds or even longer.
Its scientific status is unusual: many reports exist, but reliable measurements are scarce, and no single theory fully explains the phenomenon. Proposed explanations include glowing vaporized soil, plasma structures, chemical reactions, and microwaves trapped inside a plasma bubble. Laboratory experiments have produced ball-like luminous effects, but their connection to naturally occurring ball lightning remains uncertain.
Ball lightning is not the same as St. Elmo’s fire, which is a glow around pointed objects in a strong electric field. It is also distinct from a fireball or a plasma globe, neither of which is the standard name for this atmospheric phenomenon.