Oct. 2, 2015

To see how this event may affect Earth, please visit NOAA's Space Weather Prediction Center, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.
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: NASA's Solar Dynamics Observatory captured this image of a solar flare – as seen in the bright flash on the lower right limb of the sun – at 8:12 p.m. EDT on Oct. 1, 2015. The image is a blend of three wavelengths of extreme ultraviolet light that have been colorized.