Lessons in astronomy including uranography. A brief intoductory course without mathematics (1896)
Young, Charles A. (Charles Augustus), 1834-1908 · Boston, London, Ginn and company · leaf 129
sified in bright- 118 THE PHOTOSPHERE. [§ 165 ness. When one of them passes off the edge of the disc, it issometimes seen as a little projection. The fact, however, thattheir spectrum shows bright lines of calcium vapor, makes ituncertain whether they may not be clouds of that substancefloating… … Fig. 29. — Faculse at Edge of the Sun (De La Rue). formed by the condensation of water-vapor, floats in the earthsatmosphere. Such a cloud, while at a temperature even lowerthan that of the surrounding gases, has a vastly greater powerof emitting light, and therefore appears very brilliant in…
Astronomy
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
