Samuel Pierpont Langley (; August 22, 1834 – February 27, 1906) was an American
astronomer,
physicist,
inventor of the
bolometer and pioneer of
aviation. He attended
Boston Latin School, graduated from
English High School of Boston, was an assistant in the
Harvard College Observatory, then moved to a job ostensibly as a professor of mathematics at the
United States Naval Academy, but actually was sent there to restore the Academy's small observatory. In 1867, he became the director of the
Allegheny Observatory and a professor of astronomy at the
Western University of Pennsylvania, now known as the
University of Pittsburgh, a post he kept until 1891 even while he became the third Secretary of the
Smithsonian Institution in 1887. Langley was the founder of the
Smithsonian Astrophysical Observatory.