M9.3 Solar Flare October 24, 2013
On October 24th at 00:30 UT, Earth-facing Active Region AR11877 erupted, producing a powerful M9-class solar flare. Earth’s magnetic field is about to receive an impact from three CMEs observed leaving the Sun between Oct. 20th and 22nd. Forecasting models suggest that the three clouds merged en route to Earth, and their combined impact could trigger a polar geomagnetic storm on Oct. 24-25. High-latitude sky watchers should be alert for auroras.