See Also: fraunhofer lines(medicine)
Fraunhofer's lines(medicine)
Fraunhofer lines(encyclopedia)
Fraunhofer(dictionary)
Fraunhofer, Joseph von(medicine)
Lines(medicine)
tram lines(medicine)
tender lines(medicine)
septal lines(medicine)
pleural lines(medicine)

Fraunhofer lines (sh)




In astronomical spectroscopy, dark lines in a star's spectrum caused by selective absorption of its radiation at specific wavelengths by the various chemical elements in its atmosphere.

First observed in 1802, they are named for the German physicist Joseph von Fraunhofer (1787-1826), who from งใ 1814 plotted over 500 of them and designated the brightest with the first few letters of the alphabet. About 25,000 Fraunhofer lines are known to exist in the Sun's spectrum, between the wavelengths of 2,950 and 10,000 angstroms.