"NIGHT BUTTERFLIES" OVER NORWAY: Earth is entering a stream of fast-moving solar wind. First contact on Nov. 20th produced a visually stunning episode of auroras around the Arctic Circle--including "night butterflies" over Norway. NOAA forecasters say there is a chance of G1-class geomagnetic storms on Nov. 21st as Earth moves deeper into the stream. If so, auroras could appear in northern-tier US states such as Michigan and Minnesota. Check Spaceweather.com for updates and photos.
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Above: A giant "night butterfly" over Tromsø, Norway, photographed on Nov. 20th by Markus Varik.
