As expected, a solar wind stream hit Earth's magnetic field in the early hours of Jan. 7th. The impact sparked a G1-class (Kp=5) geomagnetic storm and bright auroras around the Arctic Circle. "It was just amazing," says Kjetil Skogli, who sends this picture from Tromsø, Norway:

Aurora
© Kjetil SkogliA classic start with a faint band in the north who ended in several spectacular waves with extreme high speed rays, sharp lines and band. Just amazing Canon EOS 5D mkII, EF24mm/f1.4 . ISO 800, f1.6, 0,8 - 5 sec.
"The display began with a faint band in the north and quickly developed into several spectacular waves with extreme high speed rays," says Skogli. The lights were so intense, they could be seen as far away as Northern Ireland. "The glow was faint, but definitely there," reports Martin McKenna of Maghera, Co. Derry.

High latitude sky watchers should remain alert for auroras as the solar wind continues to blow.

More Images:
From Bernt Olsen of Tromsø, Norway; from Frank Olsen of Tromsø, Norway:

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© Frank OlsenTromsø, Norway, Jan. 7, 2011
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© Bernt OlsenTromsø, Norway, Jan. 6, 2011