The Probert Encyclopaedia of Science & Technology

LIGHTNING

Lightning is the discharge of static electricity built up in clouds by the movement and rubbing of ice and water particles at speeds of around 100 mph within the cloud which cause electrons to be split off from the ice, and scattered randomly. The static electricity builds up within the cloud, until eventually it releases itself, at first arcing between clouds and then as it grows stronger to earth as a low voltage, invisible charge which returns from the earth to the cloud as a powerful stream of lightning. Lightning is five times hotter than the sun, and this heat causes the surrounding air to explode with loud bangs (heard as thunder).
Research Lightning