The most potent magnetic events in the solar system, solar flares have the ability to unleash an enormous amount of energy exceeding $10^{-39}$ J within a matter of minutes. They emit radiation spanning the entire electromagnetic spectrum from radio waves to $\gamma$-rays. They are closely associated with the acceleration of particles into interplanetary space and the ejection of coronal mass. A flare occurs when previously stored energy in the form of inductive magnetic fields, resulting from electric currents flowing into the corona, is rapidly released. The total energy released during a flare aligns with the quantity of magnetic ‘free’ energy available in the magnetic active regions, typically found in the coronal connections of sunspot groups where most flares occur. Evaluating the magnetic free energy from observations is challenging due to its dependence on the magnetic vector field. However, in a few instances where it has been possible, researchers have found that the free energy is comparable to that of large flares. Additionally, alternative energy sources within the corona or chromosphere cannot adequately explain the energy budget of flares. Consequently, it can be concluded that the conversion of stored magnetic energy plays a central role in the flare process.

• Fletcher et al., 2011, ‘An Observational Overview of Solar Flares,’ Space Science Reviews.