HIGH SOLAR ACTIVITY: Behemoth sunspot AR1515 is crackling with M-class solar flares and appears to be on the verge of producing an X-class explosion. NOAA forecasters estimate an 80% chance of M-flares and a 25% chance of X-flares during the next 24 hours.
ACTIVE SUNSPOT: Sunspot AR1513 is crackling with impulsive M-class solar flares. NASA’s Solar Dynamics Observatory recorded the extreme ultraviolet flash from one of them at 0920 UT on June 29th:
This M2-class flare illuminated Earth’s upper atmosphere with a pulse of X-rays and extreme ultraviolet radiation. Waves of ionization rippled over Europe, altering the propagation of low-frequency radio signals around the continent. Using a receiver tuned to 60 kHz, Rob Stammes detected the sudden ionospheric disturbance over Norway. His antennas also picked up radio waves from the flare itself at 26 MHz and 56 MHz.
More ionization waves and solar radio bursts are in the offing. NOAA forecasters estimate a 40% chance of continued M-flares during the next 24 hours.