Solar Prominences, June 16, 2008. This photograph was taken with a hydrogen alpha scope that 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. They can change their shape quickly, and I could observe these ones develop while watching through the eyepiece of the telescope. Prominences follow powerful magnetic fields generated by the Sun. The Earth would be just a fraction of the height of these features. This photograph was taken at 19:30 UT.
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