After an unusually long period of quiescence, the Sun's activity started ramping up last summer.
Now sunspot group 1158 has unleashed a series of blasts culminating with an X2 flare at 1:56 UT February 15th (8:56 p.m. EST on the 14th). This is the strongest solar eruption in four years, and the impressive coronal mass ejection that accompanied it dealt a glancing blow to Earth's magnetic field three days later. The impact was smaller than expected, and only caused northern lights (or auroras, as scientists call them) in the deep arctic.
However, this flare is a clear indication that solar activity is on the increase, so observers at moderate to high latitudes should stay tuned to the aurora forecasts and keep their eyes open for unexpected auroras. And solar observers have a new, large sunspot group to watch — one that's readily visible in properly filtered binoculars. (Experienced observers don't need this warning, but you must NEVER look at the Sun without a filter specifically designed for this purpose. )
For more information on this flare, auroras — and solar activity in general — see spaceweather.com.