4.29.2009

Superfast secret of northern lights revealed

http://www.timesonline.co.uk/tol/news/uk/science/article6168928.ece
The Abisko Ark Hotel with the Aurora Borealis
DIFFERENT CULTURES have attributed their spectacular light show to fire-breathing dragons, dancing gods and ghostly clans at war.
New research, however, has found that the northern lights, or aurora borealis, are powered by giant electrical tornadoes spinning at more than a million miles an hour and stretching thousands of miles into space.
[...]
They show how vast quantities of charged particles emitted by the sun first pile up in huge clouds about 40,000 miles above the night side of Earth. Then, as the energy they hold becomes too great, the particles explode downwards towards Earth, spinning as they go.
“When these space tornadoes reach the upper atmosphere their enormous energy heats the air so strongly it starts glowing. That is what generates the aurorae,” said Professor Karl-Heinz Glassmeier, director of the Institute for Geophysics and Extraterrestrial Physics in Braunschweig, Germany.
[...]
However, since the particles hit the “day side” of Earth – the part facing the sun – and the aurorae happen on the dark “night side”, they have puzzled over how the energy is transmitted between the two sides.
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