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Related to spectroheliogram: spectroheliograph
spectroheliogram(spek-troh-hee -lee-ŏ-gram) A photograph of the solar chromosphere taken in the monochromatic light of certain strong Fraunhofer lines – usually the hydrogen-alpha (Hα) line of neutral hydrogen at 656.3 nm or the K line of singly ionized calcium at 393.4 nm – using a spectroheliograph. When a photograph is taken using a telescope equipped with a suitable narrow-band interference filter, it is usually called a filtergram. By changing the wavelength slightly, different levels in the chromosphere can be photographed and information obtained on the vertical extent of any features present.
A photograph of the sun obtained by means of a spectroheliograph.