A big new sunspot is emerging over the sun's northeastern limb. It announced itself on March 2nd at 1746 UT with an M3-class solar flare. NASA's Solar Dynamics Observatory recorded the extreme ultraviolet flash. Although the blast site was partially eclipsed by the solar limb, the flare nevertheless created waves of ionization in Earth's upper atmosphere. Dave Gradwell of Birr Ireland detected the effect of these waves on the propagation of low-frequency radio signals across Europe. The explosion also hurled a faint CME over the northeastern limb: SOHO movie. The expanding cloud is not Earth-directed. NOAA forecasters estimate a 55% chance of additional M-class flares and a 5% chance of an X-flare during the next 24 hours. Solar activity is picking up. www.spaceweather.com
UPDATE 04/03/2012: A sunspot almost four times as wide as Earth itself is rotating onto the solar disk. NASA's Solar Dynamics Observatory recorded its entrance on March 2nd and 3rd; click on www.spaceweather.com to view a 24-hour animation.
The sunspot has a 'beta-gamma' magnetic field that harbors energy for strong M-class solar flares. Indeed, it has already unleashed an M3-class eruption on March 2nd that created mild waves of ionization in the atmosphere over Europe.
Earth-effects could become stronger as the sunspot turns toward our planet in the days ahead. NOAA forecasters estimate a 55% chance of additional M-class flares and a 5% chance of an X-flare during the next 24 hours.