This new image of a mid-level solar flare was captured by NASA’s Solar Dynamics Observatory (SDO) at 8:13 p.m. EDT on October 1, 2015. The image is a blend of three wavelengths of extreme UV light that have been colorized.
SDO captured this image of an M5.5 class flare – as seen in the bright flash on the lower right limb of the Sun – on October 1. Image credit: NASA / SDO.
Solar flares are brief, huge outbursts of electromagnetic radiation from the Sun lasting from minutes to hours.
They produce enhanced emission in all wavelengths across the electromagnetic spectrum, including radio, optical, UV, hard and soft X-rays, and gamma-rays.
Solar astronomers classify flares according to their brightness in the X-ray wavelengths.
There are three categories of solar flares: C, M, and X.
The October 1 event is classified as an M5.5 class flare.
The number provides more information about its strength. An M2 is twice as intense as an M1, an M5 is five times as intense.
M-class flares are medium-sized; they generally cause brief radio blackouts that affect polar regions.
Minor radiation storms sometimes follow an M-class flare.
