The sun has emitted a mid-level solar flare, its image captured (above) by NASA’s Solar Dynamics Observatory. 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, if they are intense enough, they can disturb the atmosphere in the layer where GPS and communications signals travel.
NOAA’s Space Weather Prediction Center has further details of spce weather and how it affects us.
The flare is classified as a M6.6 flare. M-class flares are a tenth the size of the most intense flares, the X-class flares. The number provides more information about its strength. An M2 is twice as intense as an M1, an M3 is three times as intense, etc.