The Adolfo Stahl lectures in astronomy, delivered in San Francisco, California, in 1916-17 and 1917-18, under the auspices of the Astronomical Society of the Pacific (1919)
Astronomical Society of the Pacific, Aitken, Robert Grant, 1864-1951 · San Francisco Stanford University Press · leaf 246
(a) Doubling of lines in the magnetic field. (b) Doubling of line in the umbra of a sun-spot. … (c) Detail of prominence beyond the limb. (d) Detail of its projection in the disk. Photographs by F. EUer)iian. PLATE XXXVIII. Our Nearest Star, the Sun 149 Sun-spots have been observed for a hundred and fifty years.When the spot numbers are plotted for the different years theresulting curve…
Astronomy
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
