NASA�s SDO Captures Image of Mid-level Flare
The Sun emitted a mid-level solar flare, peaking at 4:33 pm EDT on September 4, 2017. NASA�s Solar Dynamics Observatory, which watches the Sun constantly, captured an image of the event. 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 M5.5 class 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.
Image Credit: NASA/SDO
Explanation from: https://www.nasa.gov/feature/goddard/2017/nasa-s-sdo-captures-image-of-mid-level-flare