Astronomy, a handy manual for students and others (1918)
Dyson, Frank Watson, Sir, 1868-1939 · New York, E.P. Dutton & Co. · leaf 124
tis more usual now to photograph the Sun, enlargingthe image formed by the object glass by means of asecond lens. Besides giving a larger picture, thishas the advantage of diminishing the brightness ofthe image. Even then it is necessary to give veryshort exposures and to use very slow plates.… … Diag. LVI.—Photograph of Sun. This photograph shows that the light of the Sunis more intense near the centre of the disc than at theedge, pointing to an absorbing smoky atmospheresurrounding the photosphere, or luminous body ofthe Sun. The light from near the limb passes througha greater depth of…
Astronomy
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