Ball lightning extra

Ball lightning is described as a luminous sphere which seems to appear out of nowhere and vanish into thin air. It varies in size from two to ten inches in diameter. It usually is seen shortly before or after, or during, a thunderstorm. Its duration varies from a few seconds to a few minutes. "The lifetime of ball lightning tends to increase with size and decrease with brightness. Balls that appear distinctly orange and blue seem to last longer than average....Ball lightning usually moves parallel to the earth, but it takes vertical jumps. Sometimes it descends from the clouds, other times it suddenly materializes either indoors or outdoors or enters a room through a closed or open window, through thin nonmetallic walls or through the chimney."

Some have speculated that ball lightning is a plasma ball, but that theory has been dismissed because a "hot globe of plasma should rise like a hot-air balloon" and that is not what ball lightning does. Many physicists have speculated that ball lightning must be due to electrical discharges. For example, Russian physicist Pyotr Kapitsa described ball lightning as an electrodeless discharge caused by a standing UHF waves of unknown origin present between the earth and a cloud.* According to another theory, "outdoor ball lightning is caused by an atmospheric maser-- analogous to a laser, but operating at a much lower energy--having a volume of the order of many cubic kilometers."

Two New Zealand scientists, John Abrahamson and James Dinniss, believe ball lightning consists of "fluffy balls of burning silicon created by ordinary fork lightning striking the earth."

According to their theory, when lightning strikes the ground, the minerals are broken down into tiny particles of silicon and its compounds with oxygen and carbon. The tiny charged particles link up into chains, which go on to form filamentary networks. These cluster together in a light fluffy ball, which is borne aloft by air currents. There, it hovers as ball lightning, or a burning orb of fluffy silicon emitting the energy absorbed from the lightning in form of heat and light, until the phenomenon burns itself out.

Ball lightning has been observed since ancient times and by thousands of people in many different places. Most physicists seem to believe that there is little doubt that it is a real phenomenon. But there is still disagreement as to what it is and what causes it.