The 'X-class' solar flare followed on the heels of mid-level flare earlier in the day.
Each flare was centered over a different area of a large sunspot group currently situated at the center of the sun, about half way through its 14-day journey across the front of the disk along with the rotation of the sun.
This labeled image taken by SDO's Helioseismic and Magnetic Imager shows the location of two active regions on the sun, labeled AR1944 and AR1943, which straddle a giant sunspot complex. A Jan. 17, 2014, X1.2-class flare emanated from an area closer to AR1943.
Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however - when intense enough - they can disturb the atmosphere in the layer where GPS and communications signals travel.
This flare is classified as an X1.2-class flare. X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.
--ANI (Posted on 08-01-2014)