Hallo,
ich zitiere hier mal die Sichtung von Terschelling, Niederlande. Sie deckt sich ganz gut mit dem was Michael in Varel gesehen hat. War also eindeutig Polarlicht. Fotos werden wohl in den nächsten Tagen auftauchen:

"First observation was made from 20:45 UT till 21:00 UT. A very obvious and bright green arc was visible up to a
height of 10 - 15 degrees. Above this arc a red curtain like arc was observed and some rather bright
yellow-white beams went up at zimut 310-320 and almost reached Casseiopeia at a height of aprox 40
degrees. Interference from the moon was high but colors of the display were visible. After this I got my camera
and returned but clouds had moved in. Green arc was still visible. After 23 UT all clouds were away and it was
extremely clear with very strong moon. A green arc like glow remained visible up to a height of 5 degrees. After
24 UT the moon was just too bright to see anything more than a faint greenish color just over the northern
horizon."
http://www.spacew.com/www/auroras.html