A strong-to-severe geomagnetic storm is in progress following the impact of a coronal mass ejection (CME) at approximately 12:15 UT on Sept. 26th.
The Goddard Space Weather Lab reports a “strong compression of Earth’s magnetosphere. Simulations indicate that solar wind plasma [has penetrated] close to geosynchronous orbit starting at 13:00UT.” Geosynchronous satellites could therefore be directly exposed to solar wind plasma and magnetic fields. High-latitude sky watchers should be alert for Northern and Southern Lights after nightfall.
Having already unleashed two X-flares since Sept. 22nd, sunspot AR1302 appears ready for more. The active region has a complex “beta-gamma-delta” magnetic field that harbors energy for strong M- and X-classeruptions. Flares from AR1302 will become increasingly geoeffective as the sunspot turns toward Earth in the days ahead.
On Sunday, Sept. 25th, Dutch astrophotographer Emil Kraaikamp took a magnificent picture of the active region, which is so big only half of it fits on the screen. Click to view the entire sunspot:
The WUWT Solar reference page has more data and imagery.