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flash spectrum:see chromospherechromosphere
[Gr.,=color sphere], layer of rarefied, transparent gases in the solar atmosphere; it measures 6,000 mi (9,700 km) in thickness and lies between the photosphere (the sun's visible surface) and the corona (its outer atmosphere).
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flash spectrumThe emission spectrum of the solar chromosphere and E-corona. It is observable only for a few seconds during a total solar eclipse, at the beginning and end of totality. The majority of the spectral lines have the same wavelengths as the Fraunhofer lines of the photospheric spectrum. Their presence in successive spectrograms taken during an eclipse provides information on the distribution of elements in the chromosphere.
flash spectrum[′flash ‚spek·trəm]
The emission spectrum of the sun's chromosphere, observed for a few seconds just before and just after a total solar eclipse.