A space weather forecast

WEEKEND GEOMAGNETIC STORM LIKELY

 NOAA forecasters estimate a 60% to 70% chance of polar geomagnetic storms this weekend. A CME ejected from the sun on Aug. 21 is expected to hit Earth's magnetic field on Aug. 24, with reverberations from the impact continuing through Aug. 25. High-latitude sky watchers should be alert for auroras.

Around the Arctic Circle, summer is long and bright. Auroras vanish in the glow of the midnight sun. News flash: the auroras are back. "Tonight I saw the first auroras of the new season in Oulu, Finland," says Thomas Kast, who took this picture on August 22nd:

 

"This is how the sky looked at ten minutes past midnight," says Kast. "The orange color on the left is twilight, just between sunset and sunrise, and the waves of the Baltic Sea were lit up by the Full Moon. Above it all were some surprisingly strong Northern lights. I saw needles, purple color, and even a very faint corona."

With autumn approaching, Arctic nights are rapidly darkening.