Fraunhofer lines

American  

plural noun

Astronomy.

1. the dark lines of the solar spectrum.

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Fraunhofer lines British  

/ ˈfraunhoːfər /

plural noun

1. a set of dark lines appearing in the continuous emission spectrum of the sun. It is caused by the absorption of light of certain wavelengths coming from the hotter region of the sun by elements in the cooler outer atmosphere

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Etymology

Origin of Fraunhofer lines

First recorded in 1830–40; named after J. von Fraunhofer

Example Sentences

In his series "Fraunhofer Lines", blocks of color and shadow are set against heavily censored government reports, such as that by the U.S Senate into torture allegations at the base in Guantanamo Bay.

From Reuters

That’s where NASA’s Joanna Joiner of the Goddard Space Flight Center in Greenbelt, Md., and Christian Frankenberg of the Jet Propulsion Laboratory in Pasadena, Calif., came in, with their innovative use of an electromagnetic phenomenon known as Fraunhofer lines.

From Washington Post

These bands are so pronounced in the part of the spectrum between the Fraunhofer lines F and D, as to leave the solar spectrum unrecognizable....

From Project Gutenberg

Consequently they are known as Fraunhofer lines, or dark absorption lines.

From Project Gutenberg

This photograph completely confirms Young’s discovery, and shows the prominent Fraunhofer lines bright, the bright lines of the chromosphere spectrum being especially conspicuous.

From Project Gutenberg