Lightning generation in planetary atmospheres

The possibilities of lightning generation on other planets are considered, and the basic conditions that exist in terrestrial clouds during lightning discharges and the various theories of charge separation are reviewed. The properties of terrestrial clouds that produce lightning, the properties of lightning itself, and the fairweather field are first reviewed. The general requirements and the different proposed charging mechanisms for electrification of terrestrial clouds are discussed. The mechanisms of electrical breakdown and whistler production are considered, and recent observations of extraterrestrial lightning and of clouds on other planetary bodies are summarized. Circumstances likely to account for lightning activity on Jupiter and Venus and for electrical activity on Mars and in the rings of Saturn are discussed.