Yesterday we saw an M6.5 flare from active region 12372 followed by a filament liftoff, which turned into a coronal mass ejection, which became a a strong geomagnetic storm. Here are the NASA iSWA Kp values for the last four to show you how the Earth responded to the CME. Kp is a measure of the magnetic storm intensity, averaged over the many stations that measure the Earth's magnetic field. The NOAA SWPC has issued a G2 alert for today, meaning moderate storm activity should continue. The Kp index is described at the
Helmholtz Centre Potsdam - GFZ German Research Centre for Geosciences.
Soon after the flare, another filament rose off the surface. It will probably strike the Earth's magnetosphere tomorrow (June 24). This means the geomagnetic storm will continue for awhile. Great aurora come from these storms, but they also produce energetic particles and currents in ground-based pipelines and electrical wires.
Welcome to the declining phase of Solar Cycle 24!
