Solar Prominences, July 20, 2013. This photograph was taken with a hydrogen alpha scope which only shows one wavelength of light, at 656.3 nanometres. This is the particular wavelength of hydrogen alpha light. Observing the Sun in hydrogen alpha makes it possible to see structural details.
Large prominences of plasma lift off the surface of the Sun at tremendous speeds, and they are most easily seen along the edge with the darkness of space behind them. This moderately large prominence at the upper part of the Sun, held aloft by an immense magnetic arch, is many times larger than the Earth. The patchy texture on the Sun's surface is caused by active convection cells which are driven by both heat exchange and magnetic fields..
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