The sun started this week off with a bang, generating a mid-level solar flare that peaked on January 12. Captured here by NASA's sun-watching satellite the Solar Dynamics Observatory, the event was the first significant flare of the year—but it certainly won't be the last.

Solar flares are bursts of powerful radiation that happen when pent up magnetic energy in the sun's atmosphere is suddenly released. While the number and strength of solar flares in a year varies based on the sun's 11-year activity cycle, even a quiet sun usually produces several flares annually. Earth's atmosphere mostly protects us from the onslaught of radiation, although strong flares can disrupt GPS and communications signals. Flares can also send clouds of solar particles racing into space, and if they hit Earth, the particles can spark brilliant aurora displays.