Lightning

Monday, October 27, 2008

Lightning is a flash of light caused by the discharge of atmospheric electricity from one cloud to another or between a cloud and the earth. The discharge of electricity occurs when the clouds have become electrically charged, that is to say ionized, positively and negatively. A bolt of lightning can travel at speeds of 70,000 meter per second, reaching temperatures of 30,000ยบ C. Lightning can also occur within the ash clouds from volcanic eruptions, or can be caused by violent forest fires which generate sufficient dust to create a static charge.