Charles Greeley Abbot (1872 - 1973)

Charles Greeley Abbot (May 31, 1872 – December 17, 1973) was an American astrophysicist and the fifth secretary of the Smithsonian Institution, serving from 1928 until 1944. As an astrophysicist, he researched the solar constant, research that led him to invent various patented solar energy inventions.