A solar flare is a violent explosion in a star's( like the Sun's) atmosphere releasing up to a total energy of 6 × 1025Joules. Solar flares take place in the solar corona an chromosphere, heating plasma to tens of millions of kelvins and accelerating electrons, protons and heavier ions to near the speed of light. They produce electromagnetic radiation across the electromagnetic spectrum at all wavelengths from long-wave radio to the shortest wavelength gamma rays. Most flares occur in active regions around sunspots, where intense magnetic fields emerge from the Sun's surface into the corona. Flares are powered by the sudden (timescales of minutes to tens of minutes) release of magnetic energy stored in the corona.