Time to break out the old book map.
The sun emitted a mid-level solar flare, peaking at 9:59 p.m. EDT on Oct. 21, 2014. NASA’s Solar Dynamics Observatory, which is always observing the sun, captured an image of the event. The same active region previously emitted an X1.1 solar flare on Oct. 19. 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.