Visible solar spectrum

Visible solar spectrum

Fig. 1.21 . A spectrograph has spread out the visible portion of the Sunís radiation into its spectral components, displaying radiation intensity as a function of wavelength. When we pass from short wavelengths to longer ones (left to right and top to bottom), the spectrum ranges from violet through blue, green, yellow, orange and red. Dark gaps in the spectrum, called Fraunhofer absorption lines, represent absorption by atoms or ions in the Sun. The wavelengths of these absorption lines can be used to identify the elements in the Sun, and the relative darkness of the lines helps establish the relative abundance of these elements. (Courtesy of NSO/NOAO.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University