A
solar flare is a sudden flash of brightness observed near the
Sun's surface. It involves a very broad spectrum of emissions, requiring an energy release of up to 6 × 10
25 joules of
energy (roughly the equivalent of 160,000,000,000 megatons of TNT, over 25,000 times more energy than released from the impact of
Comet Shoemaker–Levy 9 with Jupiter). Flares are often, but not always, accompanied by a spectacular
coronal mass ejection. The flare ejects clouds of electrons, ions, and atoms through the corona of the sun into space. These clouds typically reach
Earth a day or two after the event. The term is also used to refer to similar phenomena in other stars, where the term
stellar flare applies.