A CME (Coronal Mass Ejection) hit Earth's magnetic field on Oct. 24th at approximately 1800 UT (02:00 pm EDT; 08:00 pm Swedish Time). Acording to analysts at the Goddard Space Weather Lab, the impact caused a strong compression of Earth's magnetic field, allowing solar wind to penetrate all the way down to geosynchronous orbit for a brief period between 19:06 UT and 19:11 UT. Earth-orbiting spacecraft could have been directly exposed to solar wind plasma during that time.
The impact also sparked a geomagnetic storm, underway now. Geir Øye sends this picture from Ørsta, Norway:
"The sky was brightly illuminated by auroras this evening," says Øye. "The picture, above, was taken at 19.20 UT [just after the most extreme compression of the magnetosphere]."
High-latitude sky watchers should remain alert for auroras as Earth's magnetic field continues to reverberate from the CME impact. The best time to look is usually during the hours around local midnight.
