The Encyclopedia Americana (1920)/Abbot, Charles Greely

ABBOT, Charles Greely, American astro-physicist: b. Wilton, N. H., 31 May 1872. After graduating from the Massachusetts Institute of Technology, in 1894, he was appointed assistant at the Smithsonian Astrophysical Observatory. In 1907 he was advanced to the position of acting director, becoming director a few months later. During this period he attracted much attention by his researches in solar radiation. In collaboration with S. P. Langley he completed and published the mapping of the infra-red solar spectrum, described in Vol. I of the ‘Annals’ of the Astrophysical Laboratory. More recently his studies have been of the total amount and variability of solar radiation, its absorption in the solar and terrestrial gaseous envelopes and its effects on climatic conditions. He has written numerous articles on the apparatus, methods and results of solar research, but his chief work is ‘The Sun’ (1911).