Full Moon
Auroras
Auroras are dancing around the Arctic Circle bright enough to see through the glare of the full Moon. The source of the display is a stream of solar wind that is pressing against Earth's magnetic field. Anne Birgitte Fyhn sends this picture, taken last night at moonrise, from Tromsø, Norway:
"The sky was partly cloudy, and for a couple of minutes some bright and flashing auroras danced above the full Moon and its halo," says Fyhn.
The circular halo around the Moon is a sign of ice crystals in the clouds. Pencil-shaped crystals catch the rays of the Moon and bend them into a ring 22o in diameter. Normally, icy clouds and moonlight interfere with the visibility of auroras. In this case, however, they added an extra dash of beauty.
More moonlit auroras are in the offing. NOAA forecasters estimate a 30% chance of polar geomagnetic storms on Nov. 7th as the solar wind continues to blow.
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