A solar flare is a large explosion in the Sun's atmosphere that can release as much as 6 × 10 to the power of 25 joules of energy. The term is also used to refer to similar phenomena in other stars, where the term stellar flare applies.

Solar flares affect all layers of the solar atmosphere (photosphere, corona, and chromosphere), heating plasma to tens of millions of Kelvin and accelerating electrons, protons, and heavier ions to near the speed of light. They produce radiation across the electromagnetic spectrum at all wavelengths, from radio waves to gamma rays. Most flares occur in active regions around sunspots, where intense magnetic fields penetrate the photosphere to link the corona to the solar interior. Flares are powered by the sudden (the timescale of minutes to tens of minutes) release of magnetic energy stored in the corona. If a solar flare is exceptionally powerful, it can cause coronal mass ejections.

There is no proof, so far, that a solar flare has caused an E.L.E. On any scale. Which does not mean that it has not happened. Moreover, that it could not happen in the future. Solar flares have, roughly, an 11 year cycle. So even, if the Solar flare is not of a great magnitude, combined with other elements, it could end all life on our planet.  With a weakened magnetic field, our planet will be very vulnerable indeed. As our Ozone Layer depletes, we will be in more and more trouble. All of this happens on a regular basis.

Our major problems start if there is ever a sustained super solar flare. Current methods of flare prediction are problematic, and there is no certain indication that an active region on the Sun will produce a flare. However, many properties of sunspots and active regions correlate with flaring. For example, magnetically complex regions, based on line-of-sight magnetic field, called delta spots produce most large flares. A simple scheme of sunspot classification due to McIntosh is commonly used as a starting point for flare prediction But we can not stop them from happening.