Physics of ball lightning

Abstract

An up to date description of the state of the ball lightning problem is given. The properties of ball lightning have been derived from a statistical treatment of thousands of observations. The experimental modeling of ball lightning as a whole is reviewed. The analysis leads to the conclusion that ball lightning has a rigid skeleton; a spotted structure of its glowing follows from a large difference between the radiative and mean temperatures of the ball lightning. Ball lightning is a many-sided phenomenon, and therefore has a number of analogs which are related to its separate properties and which can be modeled. The mechanical, gas-dynamical, energetic radiative and electrical processes of ball lightning are analyzed on the basis of such analogs and recent scientific information. According to this analysis, the substance composing ball lightning has a sparse fractal structure, similar to an aerogel, with the density of a gas and the behavior of a solid or liquid. The best model resembling the ball lightning structure is a knot of fractal fibers. The glowing of ball lightning is created by many thermal waves that propagate along separate fibers, use the surface energy of the structure, and form glowing hot zones with a temperature of about 2000 K. A number of models considered allow us to study the nature of ball lightning in detail.