Simon Newcomb (March 12, 1835 - July 11, 1909) was a Canadian-American polymath. He made important contributions to astronomy, mathematics, economics and statistics. In 1861 he became professor of mathematics and astronomer at the US Naval Observatory and set to work on the measurement of the position of the planets as an aid to navigation. In 1877 he became director of the Nautical Almanac Office where he embarked on a program of recalculation of all the major astronomical constants. It was soon after that he met a young naval officer and physicist Albert Abraham Michelson who was also planning such a measurement. Michelson published his first measurement in 1880, Newcomb's measurement was substantially different. In 1883, Michelson revised his measurement to a value closer to Newcomb's. He spoke French, German, Italian and Swedish; was an active mountaineer; widely read; and authored a number of popular science books. He died in 1909, at the age of 74, from bladder cancer and was buried with military honors in Arlington National Cemetery.