OLAR FLARE AND RADIO BLACKOUT: Sunspot AR2257 erupted on Jan. 13th, producing an M5-class solar flare at 04:24 UT. A pulse of extreme UV radiation from the flare ionized Earth’s upper atmosphere over Australia and the Indian Ocean. Mariners and ham radio operators may have noticed a brief communications blackout at frequencies below about 10 MHz. This map from NOAA shows the affected region:
We do not yet know if the flare also produced a coronal mass ejection (CME). If so, the plasma cloud will probably miss Earth because of the sunspot’s off-center location on the solar disk.
More flares could be in the offing. AR2257 has an unstable ‘beta-gamma-delta’ magnetic field that seems poised to explode again. NOAA forecasters estimate a 40% chance of M-class flares and a 10% chance of X-flares on Jan. 13th.