Five sunspots caused February’s solar flare

BBC : The massive solar flare of 15 February was caused by five rotating sunspots working in concert. Sunspots are centers of intense magnetic activity on the Sun’s surface; solar flares occur when some of that magnetic energy is released over a period of minutes to tens of minutes. The sunspots involved in February’s flare rotated through as much as 130 degrees as they developed, and they injected enough energy into the Sun’s atmosphere to produce the largest flare seen in more than four years. The flare and its resultant coronal mass ejection (CME) caused no significant disruption to electronic communications or other infrastructure, despite their size. CMEs can cause disruption to satellites and telecommunications, but the alignment between Earth’s magnetic field and that of the CME itself dampened the potential effects.