The American astronomer Simon Newcomb (1835-1909) was important in government scientific circles during the late 19th century. Primarily a mathematical astronomer, he studied the motion of the moon and the planets and redetermined various astronomical values.

Simon Newcomb was born on March 12, 1835, at Wallace, Nova Scotia, the son of an itinerant New England schoolteacher. Apprenticed at the age of 16 to a herbalist doctor, Newcomb ran away 2 years later to the United States. He taught at country schools in Maryland for several years and in 1857 was appointed a computer in the Nautical Almanac Office, then located at Harvard University, although the Almanac was published by the Federal government. He took advantage of his stay at Harvard by attending the Lawrence Scientific School, from which he received a bachelor of science degree in 1858. He married Mary Caroline Hassler in 1863.

Newcomb's government service continued from 1857 until his retirement in 1897. In 1861 he was commissioned professor of mathematics in the U.S. Navy and shortly thereafter was assigned to the Naval Observatory and Nautical Almanac Office. At the observatory he began his mathematical investigations of such fundamental questions as the orbits of Neptune and Uranus, the motion of the moon, and the right ascensions of the equatorial fundamental stars. His revision of the value of the solar parallax published in 1867 remained standard until 1895, when it was superseded by his own revision.

In 1877 Newcomb was appointed superintendent of the American Ephemeris and Nautical Almanac Office. He immediately began a reorganization of the office and a program to reform the entire basis of fundamental data involved in the computation of the ephemeris. Most of this reformation, a monumental task involving virtually a recomputation of all known astronomical measures, was completed during his lifetime.

As early as 1867 Newcomb had suggested the desirability of accurately determining the velocity of light as a means of obtaining a reliable value for the radius of the earth's orbit. In 1878 he began the experiments, for a while collaborating with Albert Michelson, whose later works far overshadowed Newcomb's efforts in this line.

In addition to a large number of papers on almost every branch of astronomy, Newcomb published a number of mathematical textbooks and several astronomical books for a popular audience, including Popular Astronomy (1878), The Stars (1901), Astronomy for Everybody (1902), and his autobiographical Reminiscences of an Astronomer (1903). He also wrote a novel, His Wisdom, the Defender (1900), and three books and a large number of articles on economics, a subject on which he was considered a great authority in his day. He died in Washington, D.C., on July 11, 1909.

Further Reading

• Except for William W. Campbell's Biographical Memoir: Simon Newcomb, 1835-1909 (1924), the only source for Newcomb's life is his own Reminiscences of an Astronomer (1903).
• Moyer, Albert E., A scientist's voice in American culture: Simon Newcomb and the rhetoric of scientific method, Berkeley: University of California Press, 1992.