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SPECTRAL FORMATIONKirchhoff's Laws |
Kirchhoff's Laws:
Law I: A hot opaque body, such as a hot, dense gas (like a lightbulb) or a hot solid material (like the coils on your electric stove) produces a continuous spectrum
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Law II: A hot, transparent gas produces an emission line spectrum
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Law III: A cool, transparent (dilute) gas in front of a hotter source of continuous emission produces an absorption line spectrum.
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![]() | This implies that the continuous emission from stars comes from the dense, hot regions of the atmosphere while the absorption lines are formed in cooler layers overlying the opaque regions. This picture is roughly correct, however, we know that it is an oversimplification. In reality, the continuum and the spectral lines are formed over larger regions and the regions over which they are formed are not distinct from one and another. |