Main Index Section IndexIn its simplest terms a solar flare is a rapid brightening in the solar atmosphere. However, this a major understatement since flares are the most violent eventsin the solar system. Typically, a major solar flare can release the order of 10 Joules of energy in a matter of an hour or so. While clearly seen in H alpha, flares release energy right across the whole electromagnetic spectrum.
One major puzzle is to explain how this vast amount of energy is stored and then released. The only available energy source is the coronal magnetic field. Thus, the magnetic field needs to be stable while excess magneticenergy is stored in it and, then, an instability is needed to release the energy. Magnetic reconnection is thought to be the mechanism responsible for converting the magnetic energy into heat and plasma motion.
Major solar flares are commonly associated with the eruption of prominences and coronal mass ejections.
The picture shows a flare in H alpha occurring to the right of the sunspot.
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