(b. Wallace, Nova Scotia, Canada, 12 March 1835; d. Washington, D.C., 11 July 1909), astronomy.
Simon Newcomb was the most honored American scientist of his time. During his lifetime his influence on professional astronomers and laymen was unparalleled, and it is still widely felt today. Having revolutionized the observational methods of the United States Naval Observatory, he reformed the entire theoretical and computational basis of the American Ephemeris. The planetary theories and astronomical constants that he derived are either still in official use or have been superseded only recently. Newcomb’s discovery of the departure of the moon from its predicted position led to the investigations on the variations in the rate of rotation of the earth. These inquiries dominated dynamical astronomy during the first half of the twentieth century.
Though almost wholly of New England ancestry, Newcomb was born in Canada, the elder son of John Burton Newcomb, an itinerant country schoolteacher, and Emily Prince, daughter of a New Brunswick magistrate. Newcomb’s early years were spent in various villages in Nova Scotia and Prince Edward Island. At the age of sixteen he was apprenticed to one Dr. Foshay, on the understanding that in return for schooling in “medical botany” he would serve as general assistant for five years. Dr. Foshay was a quack, and Newcomb ran away empty-handed, after serving two years. He walked most of the 120 miles to Calais, Maine, where he was befriended by a sea captain who agreed to let him work his passage to Salem, Massachusetts. There he was met by his father and they journeyed together to Maryland.
Newcomb obtained a teaching post at a country school at Massey’s Cross Roads, Kent County, and a year later he moved to a school in nearby Sudlersville. In his spare time he taught himself mathematics, studying in particular Newton’s Principia. In 1856 Newcomb became a private tutor nearer Washington and frequently traveled to the capital; he visited the library of the Smithsonian Institution and secured secretary Joseph Henry’s permission to borrow the first volume of Bowditch’s translation of Laplace’s Mécanique céleste—a work that proved then to be somewhat beyond his mathematical powers. Soon afterward he met Henry, who suggested he seek employment at the Coast Survey. He was in turn recommended to the Nautical Almanac Office, then located in Cambridge, Massachusetts. Newcomb arrived there at the beginning of 1857 and a few weeks later was given a trial appointment as an astronomical computer. He also took the opportunity of studying mathematics under Benjamin Peirce at the Lawrence Scientific School of Harvard University and graduated the following year.
The outbreak of the Civil War in 1861 brought the resignations of several of the professors of mathematics attached to the United States Navy, and Newcomb was invited to fill a vacancy at the Naval Observatory. He was assigned to assist in observing the right ascensions of stars with the transit circle. He deplored the random observation of stars, as was customary, and was dismayed that there was no concerted action with the person observing declinations with the mural circle. In 1863 he was placed in charge of the mural circle, and he proposed to Superintendent Gilliss a plan, based largely on the practice at European observatories, whereby the right ascension and declination observations would be conducted more systematically. When a new transit circle was acquired in 1865 Newcomb initiated a four-year program of fundamental observations of stellar positions, involving both day and night measurements.
Newcomb had great respect, but no particular love, for observational work. While in Cambridge he had put the principles of the Mécanique céleste to good use and studied the secular variations in the motions of some of the minor planets. He showed that their orbits did not intersect and that there was no reason for accepting the then prevalent hypothesis that the minor planets were fragments of a larger planet that had exploded or been shattered by a collision.
After moving to Washington, Newcomb became especially interested in the motion of the moon and in the accuracy of Hansen’s lunar tables. It soon became clear that the moon was starting to deviate from its predicted position. Hansen had fitted his theory to observations back to 1750, and in order to study the deviation it was desirable to make use of even earlier observations. Surmising that older records of occultations of stars by the moon existed in the archives of the Paris Observatory, Newcomb visited Paris during the siege of 1871 (departing only three weeks before the observatory found itself in the line of retreat of the Commune) and located a wealth of high-quality observations extending back to 1672. His analysis of these and other observations revealed that Hansen’s tables were considerably in error prior to 1750. He suspected that the discrepancy was due to variations in the rate of rotation of the earth—and thus in the astronomical reckoning of time—but his attempt to verify this from observations of transits of Mercury was inconclusive (1882). Newcomb again took up the problem of the “fluctuation” in the motion of the moon during the final years of his life, and his exhaustive discussion of lunar observations from 720 B.C. to A.D. 1908 was completed only a month before his death. It remained for Brown, Innes, Spencer Jones, de Sitter, and others to prove that the cause of the fluctuation is indeed the irregular rotation of the earth.
In 1875 Newcomb was offered the directorship of the Harvard College Observatory, which he declined. In 1877 he was appointed superintendent of the Nautical Almanac Office, which had by then been transferred to Washington. After improving the efficiency with which the calculations for the American Ephemeris were made, he embarked on two ambitious projects: discussing the observations of the sun, moon, and planets obtained since 1750 at thirteen of the leading observatories throughout the world, and developing new theories and tables for the motions of these bodies. (He had published preliminary theories and tables for Uranus and Neptune several years earlier.) The project was clearly too much for one individual; and Newcomb thus went to considerable pains to obtain the best possible assistance. The most difficult part of the work, that of constructing the theories of Jupiter and Saturn, was entrusted to G. W. Hill. For these, Hansen’s method was employed, and Newcomb subsequently regretted that he had not used the same method for the other planets; the use of Encke’s method, although much more straightforward, introduced problems into the determination of the orbital constants that Newcomb was not able to solve. Most of the work was completed by 1895, although it was left for E. W. Brown to construct the lunar theory.
In the course of his work on planetary theory Newcomb devised a useful procedure for developing the “disturbing function” that gives the perturbative action of one planet on another. In the case of circular orbits it is usual to develop the reciprocal of the distance between the planets as a cosine series in multiples of the longitude difference between the planets, each term being multiplied by a “Laplace coefficient.” Newcomb showed that the process could easily be extended to elliptical orbits by the introduction of quantities dependent upon the multiple of the mean longitude difference and differential operators that act on the Laplace coefficients. He tabulated these quantities, now commonly known as “Newcomb operators,” out to those corresponding to the eighth power of the orbital eccentricities, although some of the final ones have been found to be incorrect.
During his early years at the Naval Observatory, Newcomb made an investigation of the solar parallax, principally from observations of Mars at its 1862 opposition. In 1870 he proposed the establishment of a committee to plan observations of the 1874 and 1882 transits of Venus, with a view to obtaining a more precise value of the solar parallax. The committee became the Transit of Venus Commission, and Newcomb was appointed secretary. The results from the 1874 transit were disappointing; and although he was very much in the minority, Newcomb seriously questioned the wisdom of dispatching expeditions to observe the 1882 transit. (He did, however, conduct an expedition to South Africa in 1882.) He felt that a better value of the parallax could be obtained from the velocity of light and the constant of aberration. Newcomb’s investigation of the velocity of light, using mirrors at the Naval Observatory, the Washington Monument, and Fort Myer, Virginia, was essentially a refinement of Foucault’s method. The value obtained was long the astronomical standard.
Newcomb’s study of the transits of Mercury confirmed Leverrier’s conclusion that the perihelion of Mercury is subject to an anomalous advance (now known to be due to relativity), and he sought vainly for an explanation. In the course of his work on the transits of Venus of 1761 and 1769 he resolved the doubts surrounding the 1769 observations of Maximilian Hell. The value for the mass of Jupiter which he determined from the observations of Polyhymnia has still not been significantly improved. Newcomb also established that the retrograde motion of the line of apsides of Saturn’s satellite Hyperion is due to the resonant influence of Titan. He was able to show that the fourteen-month period found by Chandler in the variation of latitude is due to some lack of rigidity of the earth. He studied the zodiacal light, the distribution and motions of the stars, and solar radiation.
Around 1880 Newcomb founded the Astronomical Papers Prepared for the Use of the American Ephemeris and Nautical Almanac and the greater part of the above-mentioned researches was printed in the first seven volumes of this series. He also published a short account of his work on astronomical constants under the title The Elements of the Four Inner Planets and the Fundamental Constants of Astronomy (1895). At an international conference in Paris in 1896, it was agreed that from 1901 onwards, these constants (with only minor modifications) should be used in all the national ephemerides of the world. Newcomb was also charged with completing a catalogue of the positions and motions of the brighter stars and with making a new determination of the constant of precession. Completion of this work was complicated by his automatic retirement on his sixty-second birthday (1897), but arrangements were made for him to continue on a consulting basis.
Newcomb was instrumental in securing from Alvan Clark and Sons a twenty-six-inch refractor for the Naval Observatory, and with it he made measurements of the satellites of Uranus and Neptune. He was also prominently involved in negotiations with the Clarks for a thirty-inch refractor for the Pulkovo Observatory and in the establishment of the Lick Observatory.
In addition to his many scientific papers Newcomb wrote A Compendium of Spherical Astronomy (1906). It was intended to be the first of a series of texts, and it is regrettable that he never produced any further volumes. He wrote popular works on astronomy as well as three novels, some mathematical texts, several papers on economics, psychical research, and rainmaking, and one on the “flying machine” (in which his gift of foresight completely failed him: his view that man would never fly brought him into direct conflict with the astrophysicist Samuel Pierpont Langley).
Newcomb was a member or foreign associate of the national academies or astronomical societies of seventeen countries, and he received honorary degrees from as many universities. He was one of the first lecturers at the Johns Hopkins University and became a professor there in 1884; he was awarded the Sylvester prize in 1901. Among his other awards were the Copley Medal of the Royal Society, the Gold Medal of the Royal Astronomical Society, and the (first) Bruce Medal of the Astronomical Society of the Pacific. In 1863 he married Mary Caroline Hassler. He retired from the navy with the rank of captain and was promoted to rear admiral (retired) in 1906. Newcomb was buried with military honors in Arlington National Cemetery; President Taft and the representatives of several foreign governments attended the funeral.
I. Original Works. An exhaustive bibliography of Newcomb, compiled by R. C. Archibald, is contained in Biographical Memoirs. National Academy of Sciences, 17 (1924), 19–69. The best single source of biographical information is Newcomb’s autobiography. The Reminiscences of an Astronomer (Boston-New York, 1903). Most of Newcomb’s important writings are contained in Astronomical Papers Prepared for the Use of the American Ephemeris and Nautical Almanac1–9 (1879–1913).
Among other astronomical writings, in addition to those cited in the text, are “On the Secular Variations and Mutual Relations of the Orbits of the Asteroids,” in Memoirs of the American Academy of Arts and Sciences, n.s. 5 (1860), 123–152; “An Investigation of the Distance of the Sun and of the Elements Which Depend Upon It,” in Washington Observations for 1865 (1867), app. 2; “Researches on the Motion of the Moon. Part I: Reduction and Discussion of Observations of the Moon Before 1750,” in Washington Observations for 1875 (1878), app. 2; Popular Astronomy (New York, 1878); The Stars (New York, 1901); Astronomy for Everybody (New York, 1902); “On the Position of the Galactic and Other Principal Planes Toward Which the Stars Tend to Crowd,” which is Carnegie Institute of Washington Contributions to Stellar Statistics, no. 10 (1904); “An Observation of the Zodiacal Light to the North of the Sun,” in Astrophysical Journal, 22 (1905), 209–212; Sidelights on Astronomy (New York-London, 1906); “A Search for Fluctuations in the Sun’s Thermal Radiation Through Their Influence on Terrestrial Temperature,” in Transactions of the American Philosophical Society, n.s. 21 (1908), 309–387.
Among his mathematical works are “A Generalized Theory of the Combination of Observations so as to Obtain the Best Result,” in American Journal of Mathematics, 8 (1886), 343–366; “The Philosophy of Hyperspace,” in Science, 7 (1898), 1–7.
Newcomb’s works on economics include The ABC of Finance (New York, 1877); Principles of Political Economy (New York, 1886); A Plain Man’s Talk on the Labor Question (New York, 1886).
II. Secondary Literature. Among the many accounts of Newcomb’s life and work are G. W. Hill, “Simon Newcomb as an Astronomer,” in Science, 30 (1909), 353–357; T. J. J. See, “An Outline of the Career of Professor Newcomb,” in Popular Astronomy, 17 (1909), 465–481; E. W. Brown, “Simon Newcomb,” in Bulletin of the American Mathematical Society, 16 (1910), 341–355; an obituary notice by H. H. Turner in Monthly Notices of the Royal Astronomical Society, 70 (1910), 304–310; W. W. Campbell, “Simon Newcomb,” in Biographical Memoirs. National Academy of Sciences, 17 (1916), 1–18.
For recent work on astronomical constants, see W. de Sitter (and D. Brouwer), “On the System of Astronomical Constants,” in Bulletin of the Astronomical Institutes of the Netherlands, 8 (1938), 213–231; G. M. Clemence, “On the System of Astronomical Constants,” in Astronomical Journal, 53 (1948), 169–179; “Colloque International sur les Constants Fondamentales de l’Astronomie,” in A. Danjon, ed., Bulletin astronomique, 15 (1950), 163–292; International Astronomical Union Symposium No. 21: On the System of Astronomical Constants, in J. Kovalevsky, ed., Bulletin astronomique, 25 (1965), 1–324; International Astronomical Union Colloquium No. 9: The IAU System of Astronomical Constants, in B. Emerson and G. A. Wilkins, eds.. Celestial Mechanics, IV (1971), 128–280.
For material on the rotation of the earth, see W. de Sitter, “On the Secular Accelerations and the Fluctuations of the Longitudes of the Moon, Sun, Mercury, and Venus,” in Bulletin of the Astronomical Institutes of the Netherlands, 4 (1927), 21 38; H. Spencer Jones, “The Rotation of the Earth, and the Secular Accelerations of the Sun, Moon, and Planets,” in Monthly Notices of the Royal Astronomical Society, 99 (1939), 541–558. For further calculations of the Newcomb operators, see Sh. G. Sharaf, “Teoriya dvizheniya Plutona” (“Theory of the Motion of Pluto”), in Trudy Institute Teoreticheskoi astronomii. Akademiya nauk SSSR, 4 (1955); I. G. Izsak et at., “Construction of Newcomb Operators on a Digital Computer,” which is Smithsonian Astrophysical Observatory Special Report, no. 140 (1964).
Brian G. Marsden
Internationally known during his lifetime as one of America’s greatest scientists and one of the world’s leading astronomers, Simon Newcomb (1835-1909) has only recently been recognized as the first major American mathematical economist. His four books and numerous articles on economics represent only a small part of an extraordinarily rich and varied intellectual contribution, but, as he remarked in his autobiography, economics was only his avocation.
Newcomb’s early experiences directly influenced his approach to economic and social questions. Born in Nova Scotia in humble circumstances, he received little formal education, but after a brief period as a country schoolmaster he obtained his first degree at the Lawrence Scientific School of Harvard in 1858, while employed as a computer on the Nautical Almanac. From 1861 until his retirement in 1897, he was professor of mathematics in the U.S. Navy and was superintendent of the American Ephemeris and the Nautical Almanac from 1877. His prodigious lunar investigations earned him innumerable awards and distinctions, including 17 honorary degrees from leading universities in 10 different countries. He occasionally lectured in political economy at Harvard and examined in economics at Johns Hopkins, where he was professor of mathematics and astronomy, and his bibliography includes many works on politics, education, theology, psychic research, and fictional topics, as well as his contributions to various scientific disciplines.
Having overcome his early difficulties by sheer ability, will power, and unceasing toil, Newcomb took a ruggedly individualistic view of current economic and social problems. A vigorous critic of labor unions, he wrote an unsigned review of Richard T. Ely’s sympathetic study The Labor Movement in America (1886c), denouncing his Johns Hopkins colleague as unfit to occupy a university chair. Newcomb’s first book on economics, A Critical Examination of Our Financial Policy During the Southern Rebellion (1865), attacked inconvertible paper money as immoral and inexpedient. This book, like his popular works The ABC of Finance (1878) and A Plain Man’s Talk on the Labor Question (1886a), was designed to expose the fallacies prevalent among “practical” businessmen and the general public and to show that elementary economic principles were directly applicable to current affairs. But although his lucid prose made him an effective expositor, Newcomb’s scientific training blinded him to the complexities of social processes.
During the controversy of the mid-1880s, which marks the beginning of modern American economics, Newcomb was prominent among those who defended the “orthodox,” or “old,” school of Ricardian political economy against the attacks of the “new,” German-inspired school of historical economists. His influence as president of the Political Economy Club, a small but important group of conservative economists and publicists, was enhanced by his scientific reputation, which lent additional authority to his claim that no essential methodological difference existed between the “old” and the “new” viewpoints. But although the “old” school emerged victorious in the 1890s, Newcomb became increasingly dissatisfied with the trends of academic economics, protesting that the professional economists were retreating before the rising tide of popular nostrums.
Newcomb’s enthusiasm for economics began in 1854, when he rejoiced at finding “human affairs treated by scientific method” in J. B. Say’s Political Economy. But although he was primarily interested in the practical applications of economic principles to public policy, twentieth-century economists esteem him as a mathematical theorist. Before he published his favorable review of Jevons’ Theory of Political Economy in 1872, Newcomb had discussed the theory of competitive price with the pragmatist philosopher C. S. Peirce, and unpublished manuscripts reveal his familiarity with the concept of demand elasticity and the principle of substitution. Newcomb may, however, have learned both of these ideas from reading Cournot, whereas his Principles of Political Economy (1886b) was strikingly original. In Book 4 of the Principles, entitled “The Societary Circulation,” he elaborated the crucial distinction between “fund” and “flow” concepts, tracing the interactions between currency and commodity flows. A few pages later he presented an “equation of societary circulation,” VR = KP (where V = number of dollars; R = average velocity of circulation; K = number of transactions; and P = scale of prices), which formed the basis of Irving Fisher’s well-known “equation of exchange,” MV = PT. Newcomb also anticipated Fisher’s proposal for a “compensated dollar,” the gold content of which could be varied to compensate for price changes; and his discussion of the interest rate, his distinction between prospective and actual demand, and his analysis of income and hoarding all represent significant steps toward modern macroeconomic and monetary analysis.
Unfortunately, Newcomb’s Principles was too far ahead of its time to exert much influence upon the economists of his day. Yet despite his disappointment, Newcomb’s confidence was unshaken, and in 1904 he unsuccessfully endeavored to obtain support for an ambitious systematic investigation of the “practical” operation of economic causes that was somewhat akin to a present-day econometric study. Also in that year Newcomb presided at the Congress of Arts and Science, a great international gathering of scholars at the Louisiana Purchase Exposition of 1904 at St. Louis. He remained active until his death in 1909.
A. W. Coats
[For the historical context of Newcomb’s work, see the biographies ofCournot; Ely; for discussion of the subsequent development of his ideas, seeMoney, article onQuantity Theory; and the biography ofFisher, Irving.]
1865 A Critical Examination of Our Financial Policy During the Southern Rebellion. New York: Appleton.
1872 Jevons’ Theory of Political Economy. North American Review 114:435-440.
1873 A Mechanical Representation of a Familiar Problem. Royal Astronomical Society, Monthly Notices 33: 573-574.
1878 The ABC of Finance: Or, the Money and Labor Questions Familiarly Explained to Common People, in Short and Easy Lessons. New York: Harper.
1886a A Plain Man’s Talk on the Labor Question. New York: Harper.
1886b Principles of Political Economy. New York: Harper.
1886c Dr. Ely on the Labor Movement. Nation 43:293-294.
1893 The Problem of Economic Education. Quarterly Journal of Economics 7:375-399.
1903 The Reminiscences of an Astronomer. Boston: Houghton Mifflin.
Campbell, W. W. 1924 Biographical Memoir; Simon Newcomb: 1835-1909. National Academy of Sciences,Memoirs 17:1-69. → Contains a bibliography of Newcomb’s writings prepared by R. C. Archibald.
Coats, A. W. 1961a The Political Economy Club: A Neglected Episode in American Economic Thought.American Economic Review 51:624-637.
Coats, A. W. 1961b American Scholarship Comes of Age: The Louisiana Purchase Exposition, 1904. Journal of the History of Ideas 22:404-417.
Dorfman, Joseph 1946-1949 The Economic Mind in American Civilization. Vols. 2-3. New York: Viking.
Eisele, Carolyn 1957 The Charles S. Peirce-Simon Newcomb Correspondence. American Philosophical Society, Proceedings 101:409-433.
Hutchison, Terence W. (1953) 1962 A Review of Economic Doctrines: 1870-1929. 2d ed. Oxford: Clarendon.
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.
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. □
Newcomb, Simon (1835-1909)
Newcomb, Simon (1835-1909)
Astronomer, mathematician, and first president (1885-86) of the American Society for Psychical Research. He was born on March 12, 1835, at Wallace, Nova Scotia. He studied at Lawrence Scientific School (B.S., 1858), and Harvard University. He joined the U.S. Navy during the Civil War as a professor of mathematics (1861), and was later assigned to the U.S. Naval Observatory (1867). He subsequently became the director of the American Nautical Almanac (1877-97) and a professor of mathematics and astronomy at Johns Hopkins University (1884-94). A world-famous astronomer and mathematician, Newcomb's research made possible the construction of accurate lunar tables. In spite of his interest in psychical research, he remained an outspoken skeptic, a position he explained in his autobiography. He died July 11, 1909.
Berger, Arthur S., and Joyce Berger. The Encyclopedia of Parapsychology and Psychical Research. New York: Paragon House, 1991.
Hyslop, James H. "Professor Newcomb and Occultism." Journal of the American Society for Psychical Research 5 (1909).
Newcomb, Simon. Reminiscences of an Astronomer. Boston: Houghton, Mifflin, 1903.
Pleasants, Helene, ed. Biographical Dictionary of Parapsychology. New York: Helix Press, 1964.
Simon Newcomb (nōō´kəm, nyōō´–), 1835–1909, American astronomer, b. Nova Scotia, grad. Lawrence Scientific School, Harvard, 1858. Living in the United States from 1853, he was appointed (1857) a computer on the American Nautical Almanac and later (1877–97) was its director. He was professor of mathematics in the U.S. navy from 1861 until his retirement in 1897, professor of mathematics and astronomy at Johns Hopkins from 1884 to 1894, and for several years editor of the American Journal of Mathematics. Newcomb participated in several eclipse expeditions and in 1882 went to the Cape of Good Hope to observe the transit of Venus. The record of many of his researches was published in the Astronomical Papers of the American Ephemeris, a series that he established in 1879. His investigations and computations of the orbits of six planets resulted in his tables of the planetary system, which were almost universally adopted by the observatories of the world. Newcomb urged the use of a common system of constants and fundamental stars by astronomers of all nations. A subject to which he devoted many years of study was the theory of the moon's motion. From the formulas he established it was possible to construct accurate lunar tables. His writings include a valuable early paper, On the Secular Variations and Mutual Relations of the Orbits of the Asteroids (1860) and On the Motion of Hyperion (1891).
See his Reminiscences of an Astronomer (1903); study by L. M. Dunphy (1956).