Ball Lightning Essay Research Paper Ball Lightning

  • Просмотров 135
  • Скачиваний 9
  • Размер файла 15
    Кб

Ball Lightning Essay, Research Paper Ball Lightning 59 Boules de Feu Dateline:04/17/00 Another startling sighting – and certainly one of the most detailed and scientifically credible – comes from Professor Roger Jennison (Department of Electronics, University of Kent) concerning his experiences on board a late-night flight from New York to Washington in March 1963. He later wrote of his experiences in the November 1969 issue of Nature. Jennison states that the phenomenon occurred after the aircraft encountered a thunderstorm in which it was enveloped by a bright and audible electrical discharge. Some seconds later a glowing sphere some 20cm in diameter emerged from the pilot’s cabin and passed down the aircraft’s central aisle approximately 50cm from Jennison. The

ball moved on a straight course the whole length of the aisle 75cm above the floor at a velocity relative to the aircraft of about 1.5 ms-1. It was blue-white in colour and its optical output amounted to about 5 to 10 Watts. Interestingly, no heat was felt when it passed close by and the limb darkening (like that of the Sun) gave it an almost solid appearance, indicating that it was optically opaque. No asymmetry could be seen in any dimension so it was impossible to determine whether or not it was spinning. (First published in AA&ES Magazine, June 1996) In German, ball lightning is called kugelblitz. Professor Jennison’s experience is one of the best ball lightning sightings on record. There are reports of this phenomenon going back at least to the Middle Ages, and maybe

as far back as ancient Greece. Like meteorites before it, ball lightning is one of those phenomena that science has been reluctant to accept, with a few hold-outs remaining even today. Ball lightning, or kugelblitz or boules de feu, sometimes appears high in the sky, almost always during a thunderstorm, and usually coincident with a normal cloud-to-ground lighting strike. It has been reported appear in homes and even airplanes. It’s always round, and is reported to be anywhere from a few centimeters to a meter or so in diameter. It has been variously reported as white, blue, yellow, red, orange, or green in color. It only lasts a short time, usually less than 5 seconds, but in a small number of cases it reportedly lasted over a minute. It may descend, hover, or move

horizontally, but it has rarely been reported to rise. It sometimes has a strong odor, but not always. It either vanishes silently or with a loud explosion. There are a few purported photographs of ball lightning, but it’s difficult to determine what the photos actually depict. Almost all of the evidence for the phenomenon is anecdotal, consisting of sighting reports from a variety of witnesses. There are many theories as to how ball lightning is formed, but none that satisfactorily explains its behavior. The most popular theory is that it is composed of a plasma contained within a magnetic field. Another theory is that it is a cloud of a common gas such as methane that has been ignited by a normal lightning strike. The latter theory, however, is at odds with its reported

behavior. Clouds of ignited methane would rise from the ground, rather than drop from the sky. Ball lightning has occasionally been used as an explanation for UFO sightings. As such, it has not been a very successful explanation because the reported behavior of ball lightning is not like that of reported UFOs, not to mention that very few UFO sightings occur during thunderstorms. One of the most interesting things about ball lightning is its similarity to the UFO phenomenon. In both we have a phenomenon whose appearance we can’t predict and whose origin we can’t explain. Science has, however, reluctantly come to accept ball lightning. Not so with UFOs. What’s the difference? Skeptic Robert Sheaffer briefly touches on the comparison between ball lightning and UFOs in his