Solar Storms

A solar storm (more commonly known as solar flares) is a violent explosion in the photosphere of the Sun whose energy is equivalent to millions of hydrogen bombs. Solar flares take place in the corona and chromosphere, heating plasma to tens of millions of kelvins and accelerating electrons, protons, etc.. resulting in nearly the speed of light. These eruptions produce electromagnetic radiation at all wavelengths of the electromagnetic spectrum, from long radio waves to the shortest gamma rays. Most flares occur around sunspots, where intense magnetic fields emerge from the Sun's surface to the corona. The energy associated with solar flares could take hours or days to build. However, most of the eruptions take just a few minutes to release their energy.

Solar flares were first observed in 1859. The frequency of these events varies, several eruptions a day when the Sun is particularly "active", less within a week when "quiet"... Solar activity varies over a 11-year cycle, called the solar cycle. At the peak of the cycle there are, usually, more sunspots, and hence more solar flares.

Solar flares are associated with coronal mass ejections (CME), which strongly influence our local solar meteorology. They produce energetic particle fluxes in the solar wind and Earth's magnetosphere that can present really dangerous radiation to astronauts and spacecrafts. The X-ray flux of some flares increases the ionization of the upper atmosphere, and this can interfere with radio communications on shortwave, and increase friction with low orbiting satellites, which leads to orbital decay. The presence of these energetic particles in the magnetosphere contribute to the aurora borealis and aurora australis.

　Here you can see an animated solar flare:

http://www.youtube.com/watch?v=_N2PXdq_bWE&feature=player_embedded

At the left: Layers of the sun. Solar flares occur

when plasma is heated in the corona

and the chromosphere.

References:

Wikipedia: http://en.wikipedia.org/wiki/Solar_flare

Google images: https://www.google.es/search?tbm=isch&hl=es&source=hp&biw=983&bih=554&q=erupciones+solares&gbv=2&oq=erupciones+solares&aq=f&aqi=g5g-S5&aql=&gs_l=img.3..0l5j0i24l5.4016.11735.0.15532.18.14.0.2.2.1.672.3094.2-2j3j1j2.8.0...0.0.1OPD6hVjjeM&safe=active