Simon Newcomb was perhaps America's most distinguished scientist at the start of the twentieth century as well as a prolific and accomplished writer. He was born in Nova Scotia but moved to America as a young man. From an early age he had shown mathematical ability far beyond his years, and it was after moving to the U.S. that he settled on science as his life's work. Joseph Henry, director of the Smithsonian Institution, helped Newcomb secure a job at the U.S. Navy's Nautical Almanac Office. At the same time Newcomb earned a bachelor of science degree from Harvard's Lawrence Scientific School. Work on the orbital dynamics of the asteroids first earned Newcomb widespread recognition in the astronomical community. His calculations showed that the observed orbits of the asteroids were incompatible with the theory they were the remnants of one original planet that had somehow broken apart. In 1861, Newcomb became professor of mathematics at the Naval Observatory. Later positions included that of superintendent of the Almanac Office, professor at Johns Hopkins, and presidencies of several academic and scientific organizations. Newcomb retired from the Observatory in 1897 but remained active until his death in 1909. The final decade of his life was his most prolific as a writer but he also continued to work intensively on the scientific problem that had engaged him throughout his career: more accurately calculating the motions of the planets and, especially, those of the moon. The results derived from his calculations remained standard until the advent of the Space Age. Astronomy boasts a long tradition of prominent practitioners who were also first-rate popularizers of the discipline, but Newcomb's combination of first-rate research with a wide popular presence was probably not rivalled until Carl Sagan's rise to fame in the 1970s. Newcomb's articles on science were regular fixtures in such magazines as Harper's, McClure's, and Popular Science Monthly, and his 1902 book Astronomy for Everybody, based on previously published magazine pieces, sold more than 50,000 copies. Nor did Newcomb restrict his writing to astronomy and mathematics. He held strong views on economics and published nearly four dozen books and articles in the field. He also wrote on occultism, politics, technology, invention, and penned three science-fiction stories, including a full-length novel. Late in life he also published his autobiography, Reminiscences of an Astronomer (1903).