About the filters
White lightThe full spectrum of visible light. This shows the photosphere, and is the image you see if you view the sun using a pinhole camera.
H-alphaH-alpha images are taken through a filter centered on a particular frequency of visible red light -- one of the spectral lines of Hydrogen. This light forms in the chromosphere, above the visible photosphere but below the corona.
Extreme UltravioletThis frequency of light is also formed in the chromosphere. The particular frequency used here forms high in the chromosphere and in the lower regions of the sun's corona.
X-rayThe X-rays we can see form in the outermost layer of the sun's atmosphere, the solar corona.
MagnetogramCertain frequencies of light are sensitive to the presence of magnetic fields. If we take a picture of the sun using those frequencies we can calculate the direction and intensity of the magnetic field near the solar surface. In the image used here the colors red and blue are used to indicate magnetic fields pointing toward and away from the solar surface.
Some things to ponder
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