A solar flare is a sudden brightening observed over the Sun's surface or the solar limb, which is interpreted as a large energy release of up to 6 × 1025 joules of energy (about a sixth of the total energy output of the Sun each second or 160,000,000,000 megatons of TNT equivalent, over 25,000 times more energy than released from the impact of Comet Shoemaker–Levy 9 with Jupiter). They are mainly followed by a colossal coronal mass ejection also known as a CME[1]. 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.
Solar flares affect all layers of the solar atmosphere (photosphere, chromosphere, and corona), when the medium plasma is heated to tens of millions of kelvins and electrons, protons, and heavier ions are accelerated to near the speed of light. They produce radiation across the electromagnetic spectrum at all wavelengths, fromradio waves to gamma rays, although most of the energy goes to frequencies outside the visual range and for this reason the majority of the flares are not visible to the naked eye and must be observed with special instruments.
The frequency of occurrence of solar flares varies, from several per day when the Sun is particularly "active" to less than one every week when the Sun is "quiet", following the 11-year cycle (the solar cycle). Large flares are less frequent than smaller ones.
Latest released solar flare pics:
This image captured in the 304 Angstrom wavelength, which is typically colorized in red provided by NASA shows a solar flare, lower center, erupting from the sun on Thursday, July 12, 2012
Sunspot AR 1476 compared to the size of Jupiter. Image released May 10, 2012.
This handout image provided by NASA shows a solar flare heading toward Earth.
This handout image provided by NASA, taken Sunday night, Jan. 22, 2012, shows a solar flare erupting on the Sun's northeastern hemisphere
This image provided by NASA shows the Sun unleashing a medium-sized solar flare, a minor radiation storm and a spectacular coronal mass ejection on June 7, 2011
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