# Numerov, Boris Vasilievich

# NUMEROV, BORIS VASILIEVICH

(*b.* Novgorod, Russia, 17 January 1891; *d.* 19 March 1943)

*astronomy, gravimetry*.

Numerov graduated in 1909 from the Novgorod Gymnasium and entered the faculty of physics and mathematics at St. Petersburg University. On graduating in 1913 he remained in the department of astronomy to prepare for a scientific career. In 1913–1915 he was a supernumerary astronomer at Pulkovo Observatory, where he observed on the zenith telescope. From 1915 to 1925 Numerov was astronomerobserver at the University’s astronomical observatory. In 1924 he was appointed professor of practical astronomy, higher geodesy, and the technology of computation at the university and professor of mathematics at the Mining Institute.

In 1919 Numerov organized the Computation Bureau, the aim of which was to compile an astronomical yearbook. The following year a subdivision was established, the State Computation Institute (in 1924 renamed the Leningrad Astronomical Institute and now the Institute of Theoretical Astronomy of the Soviet Academy of Sciences). From 1920 through 1936 Numerov directed the Institute. In 1926–1928 he was also director of the Leningrad geophysical observatory. From 1931 to 1935 he also headed the section of applied mathematics of the State Optical Institute. In 1929 he was elected corresponding member of the USSR Academy of Sciences. In 1934 he received a doctorate in physical and mathematical sciences.

In 1930–1934 Numerov headed the Astronomical Committee of the People’s Commissariat of Education, created to plan and organize astronomical institutions in the Soviet Union and to coordinate their work. Its successor was the Astronomical Council of the USSR Academy of Sciences. In connection with the work of the committee, Numerov traveled to Holland, France, England, Germany, and the United States, visiting astronomical observatories and observing geophysical methods of prospecting for useful minerals. In 1920–1926 Numerov was president of the Russian Astronomical Society.

Numerov’s scientific career was devoted to practical astronomy and astrometry, celestial mechanics, and gravimetry. He was notable in Soviet astronomy for having organized the construction and manufacture of gravimetric and astronomical instruments and equipment. For this purpose in 1928 he created a mechanical workshop at the Leningrad Astronomical Institute and, later, a construction bureau that produced a number of new and improved gravimeters and the first Soviet telescope—reflector with a thirty-two-centimeter mirror installed at the first mountain astronomical observatory in the Soviet Union, at Abastumani (now the Abastumani Astrophysical Observatory of the Academy of Sciences of the Georgian S.S.R.). In 1931, under the presidency of Numerov, the Commission of Astronomical Instruments was created in the All Union Cooperative of Optical-Mechanical Production. It laid the foundation for the industrial manufacture of large astronomical instruments.

Numerov’s new program and method (1916) of analyzing zenith telescope observations was used in determining variations in latitude and was later adopted at Pulkovo. He developed a complete theory of the zenith telescope and introduced formulas for the influence of instrumental errors, proposed a new method of studying the forms of pivots of transit instruments, and developed a theory of universal and photographic transit instruments. At the beginning of the 1920’s Numerov organized the compilation and publication of astronomical yearbooks, necessary for the observatories and numerous expeditions; later the Astronomical Institute also compiled and published *Morskoi ezhegodnik* (“Marine Yearbook”) and *Aviatsionny ezhegodnik*(“Aviation Yearbook”). In the astronomy of ephemerides, Numerov developed useful tables and charts for computing geographical and Gauss-Kruger rectangular coordinates.

Numerov’s new method of computing planetary perturbation was widely used in compiling the annual reference book founded by Numerov, *Efemeridi malykh planet* (“Ephemerides of Asteroids”), which acquired an international reputation. In 1923, for large-scale computation and improvements in the calculation of the orbits of asteroids, he proposed an original and effective method of integrating differential equations of celestial mechanics (the method of extrapolation). The application of this method allowed the computation in 1930 of a new and very precise ephemerides of the eighth satellite of Jupiter. After 1923 the satellite was not sighted again until it was rediscovered on 22 November 1930 by astronomers at the Lick Observatory in California.

Numerov gave a theoretical basis to the analysis of star catalogs by means of observational data on asteroids, and he proposed an original plan for international cooperation in determining the constants that characterize star catalogs. This plan was approved by the International Astronomical Union in 1935 and is now used in working the catalog of faint stars.

Numerov introduced into practice the pendulum gravimeter and the variograph for studying the upper layers of the earth’s crust in geological prospecting. He participated in about ten gravimetrical expeditions to the Urals, the Donets Basin, the Kazakh S.S.R., and other areas, testing the new instruments developed under his direction: a light quarter-second pendulum apparatus, a half-second pendulum apparatus, a gravitation torsion balance with three levers, and many others. Numerov’s plan for a general gravimetrical survey of the Soviet Union provided extremely valuable results.

## BIBLIOGRAPHY

**I.** Original Works. Numerov’s earlier works include “Nouveau programme pour le zénith -télescope ,” in *Izvestiya Pulkovskoi observatorii*, **7** , no. 1 (1916), 1–20; “Teoria universalnogo instrumenta” (“Theory of the Universal Instrument”), in *Astronomichesky ezhegodnik na*1923(“Astronomical Yearbook for 1923”; Petrograd, 1923), app. 3, 239–272; “Novy metod opredelenia orbit i vychislenia efemerid s uchetom vozmushcheny” (“;A New Method for Determining Orbits and Computing Ephemerides That Takes Into Account Perturbations”), in *Trudy Glavnoi rossiiskoi astrofizichekoi observatorii*, **2** (1923), 188–288; “A Method of Extrapolation of Perturbations,” in *Monthly Notices of the Royal Astronomical Society*, **84** (1824),592–601; “Chislennoe integrirovanie uravneny nevozmushchennogo dvizhenia v polyarnykh koordinatakh” (“Numerical Integration of Equations of Unperturbed Motion in Polar Coordinates”) in *Byulleten Astronomicheskogo Instituta*, no. 2 (1924), 7–107; “Résultats du calcul des éphémerides et des perturbations approchées des coordinates rectangularies de 99 planéts pour I’époque 1921–1925, “ in *Izvestiya Glavnoi astronomicheskoi observatorii v Pulkove*, **10** , no. 94 (1924), 58–155; “Teoreticheskie osnovania primenenia gravimetricheskogo metoda v geologii” (“Theoretical Bases of the Application of the Gravimetric Method in Geology”), in *Izvestiya Geologichekogo Komiteta*, **14** no.3 (1925), 331–347; “Calcul des échémerides pour une excentricité arbitraire,” in *Journal des Observatures*, 7 (1926), 125–130; “Berechnung der gestorten Ephemeriden nach der Extrapolationsmethode,” in *Byulleton Astronomickheskogo Instituda*, no.12 (1926), 109–120; “Hilfstafeln zur Bahnbestimmung und gestorten Ephemeridenrechnung nach der Extrspolationsmethode,” ibid., no.13 (1926), 121–152; *Programma sposoba Talk otta dlya opredelenia shiroty*(“Program of the Talcott Method for Determinning Lattitude “; Leningrad, 1927); and “Zavisimost mezhdu mestnymi anomaliami sily tyazhestii proizvodnymi ot potentsiala” (“;The Relation Between the Local Anomalies in the Force of Gravitation and the Derivatives of Potential “), in *Doklady Akademii nauk SSSR, ser.A (1929), 101–105,* and in *Zeitschrift fÜr Geophysik*, **5** , no.2 (1929), 58–62.

Later works include “Gravitatsionny variometr s tremya rychagami” (“;A Gravitational Torsion Balance with Three Levers”), in *Byulleten Astronomicheskogo Intituta*, no. 30 (1931), 103–108; “K voprosu opredelenia sistematicheskikh oshibok skloneny fundamentalnykh zvezd” (“ On the Problem of Determinning Systematic Errors in the Declination of Fundamental Stars”), ibid., no.32 (1932), 139–147; “Konstruirovanie i izgotovlenie astronomicheskikh priborov” (“The Construction and Manufacture of Astronomical Instruments”), in *Astronomia* (“Nauka v SSSR za 15 let”) “Astronomy” (“Science in the USSR During 15 Years”); (Moscow-Leningrad, 1932), 207–215; “Svetosilny fotografichesky meridianny krug” (“An Efficient Photographic Meridian Circle”), in *Astronomichesky zhurnal*, **12** (1935), 349–355, and in *Doklady Akademii nauk SSSR*, **3** (1935), 201–204; “Primenenie metoda ekstrapolirovania k tochnomy vychisleniyu vozmushchennogo dvizhenia malykh planet” (“The Use of the Method of Extrapolation for the Exact Computation of the Perturbational Motion of Asteroids”), in *Astronomichesky zhurnal*, **12** (1935), 455–475; “K voprosu o sovmestnom opredelenii popravok elementov planety i Zemli” (“On the Problem of the Simultaneous Correction of the Elements of a Planet and of the Earth”), in *Astronomichesky zhurnal*, **12** (1935), 584–593, and in *Astronomical Journal*, **45** , no. 12 (1936), 105–111; “K voprosu ob opredelenii geoida na osnovanii gravitatsionnykh nablyudeny” (“On the Problem of Determining the Geoid on the Basis of Gravitational Observations”), in *Astronomichesky zhurnal*, **12** , no. 1 (1935), 47–59; **K** voprosu opredelenia sistematicheskikh oshibok zvezdnykh polozheny” (“On the Problem of Determining Systematic Errors in Stellar Positions”), in *Doklady Akademii nauk SSR*, **2** no. 7 (1935), 451–457, in *Astronomichesky zhurnal*, **12** , no. 4 (1935), 339–348, and in *Journal des Observateurs*, **18** , no. 4 (1935), 57–64, in French; “K voprosu o postroenii fundamental’nogo kataloga slabykh zvezd” (“On the Problem of Compiling a Fundamental Catalog of Faint Stars”), in *Doklady Akademii nauk* SSSR, **12** (1936), 261–263, and in *Astronomische Nachrichten*, **260** (1936), 305–322; “Ob opredelenii figury geoida na osnovanii nablyudeny sily tyazhesti”(“On Determining the Figure of the Geoid on the Basis of Observations of the Force of Gravity”), in *Doklady Akademii nauk* SSSR, **12** (1936), 265–268, written with D. N. Khramov; “On the Problem of the Stability of the Motion of Trojans,” in *Byulleten Astronomicheskogo Instituta,* no. 41 (1936), 1–4; and “Absolute Perturbations of Polar Coordinates of Asteroids From Outer Planets,” *ibid*., no. 42 (1937), 37–57, in English and Russian.

**II.** Secondary Literature. On Numerov and his work, see S. I. Seleshnikov, in *Astronomichesky kalendar* for 1966 (Moscow, 1965), 211–214; and N. S. Yakhontova, “Boris Vasilievich Numerov, 1891–1943,” in *Byulleten Instituta teoreticheskoi astronomii*, **9** , no. 3 (1963), 213–215, with portrait.

P. G. Kulikovsky

#### More From encyclopedia.com

#### You Might Also Like

#### NEARBY TERMS

**Numerov, Boris Vasilievich**