Severe Geomagnetic activity
Sunspot 798/808 flared twice more yesterday, and at least one of the X-class explosions propelled a coronal mass ejection (CME) toward Earth. NOAA forecasters estimate a 70% chance of severe geomagnetic activity when the CME arrives--perhaps tonight, Sept. 14-15. Sky watchers at all latitudes should be alert for auroras.
Observing tips: Although auroras are sometimes bright enough to shine through city lights, you'll see more from a dark-sky site in the countryside. The best time to look is usually during the hours around local midnight.