Some Obscurish facts
#125
A new class of lightning has been discovered, consisting of at least three types of lightning associated with severe thunderstorms. All three confirmed types occur far above the cloud layer, jumping from the tops of the clouds into the stratosphere and lower ionosphere, and are much rarer than normal lightning. The first type, called a red sprite, is a dim, reddish-colored burst that lasts only a few thousandths of a second and can be many kilometres wide. Red sprites appear suddenly, usually in clusters of two or more, and rise to heights of about 50 to 100 km (30 to 50 mi) above the cloud layer. They travel at up to a tenth of the speed of light - 67 million miles (107 million km) per hour! The second type, a blue jet, is a cone-shaped burst, brighter and far more powerful than a red sprite. Blue jets erupt from the center of a thunderstorm at up to 6000 km/h (3300 mph), rising to heights of about 20 to 50 km (10 to 30 mi) above the cloud layer. Red sprites and blue jets were first photographed in 1989 in Minnesota by American physicist John R. Wincklyer, and continue to be intensely studied. A third type of cloud-to-stratosphere lightning, called Elves, was announced in 1995. Elves are saucer - or doughnut- shaped bursts of light about 400 km (about 250 mi) wide that occur about 100 km (about 60 mi) above the cloud tops. They are thought to be greenish, but they last such a short time (less than a thousandth of a second) that scientists have not yet determined their colour. A fourth variety, not surprisingly called trolls, is still poorly understood.
A new class of lightning has been discovered, consisting of at least three types of lightning associated with severe thunderstorms. All three confirmed types occur far above the cloud layer, jumping from the tops of the clouds into the stratosphere and lower ionosphere, and are much rarer than normal lightning. The first type, called a red sprite, is a dim, reddish-colored burst that lasts only a few thousandths of a second and can be many kilometres wide. Red sprites appear suddenly, usually in clusters of two or more, and rise to heights of about 50 to 100 km (30 to 50 mi) above the cloud layer. They travel at up to a tenth of the speed of light - 67 million miles (107 million km) per hour! The second type, a blue jet, is a cone-shaped burst, brighter and far more powerful than a red sprite. Blue jets erupt from the center of a thunderstorm at up to 6000 km/h (3300 mph), rising to heights of about 20 to 50 km (10 to 30 mi) above the cloud layer. Red sprites and blue jets were first photographed in 1989 in Minnesota by American physicist John R. Wincklyer, and continue to be intensely studied. A third type of cloud-to-stratosphere lightning, called Elves, was announced in 1995. Elves are saucer - or doughnut- shaped bursts of light about 400 km (about 250 mi) wide that occur about 100 km (about 60 mi) above the cloud tops. They are thought to be greenish, but they last such a short time (less than a thousandth of a second) that scientists have not yet determined their colour. A fourth variety, not surprisingly called trolls, is still poorly understood.