| Administrative and Honorary Positions |
| 1931-34 | Lecturer (Associate Professor) of Astrophysics at Leningrad State University (LSU) |
| 1931-35 | Research Associate of Pulkovo Observatory |
| 1931-32 | Scientific Secretary of Pulkovo Observatory |
| 1933-34 | Head of the Division of Astrophysics of LSU Astronomical Observatory |
| 1934-46 | Head of the first in the Soviet Union Chair of astrophysics at LSU |
| 1937-44 | Scientific Head of Yerevan Astronomical Observatory |
| 1939-41 | Director of LSU Astronomical Observatory |
| 1941-43 | Pro-Rector of LSU on scientific affairs |
| 1941-43 | Head of the Scientific-Research branch of LSU, evacuated to Elabuga (Tatar ASSR) |
| 1943-47 | First Vice-President of the Armenian SSR Academy of Sciences |
| 1944-94 | Head of the newly created Chair of Astrophysics at Yerevan State University |
| 1944-46 | Director of Yerevan Astrophysical Observatory of the Armenian SSR Academy of Sciences |
| 1946-88 | Director of Byurakan Astrophysical Observatory (BAO) of the Arm. SSR Academy of Sciences |
| 1947-93 | President of the Armenian SSR Academy of Sciences |
| 1948-55 | Vice-President of the International Astronomical Union (IAU) |
| 1961-64 | President of the International Astronomical Union (IAU) |
| 1968-70 | President of the International Council of Scientific Unions (ICSU) (first term) |
| 1970-72 | President of the International Council of Scientific Unions (ICSU) (second term) |
| 1988-96 | Honorary Director of Byurakan Astrophysical Observatory (BAO) |
| 1990 | Honorary President of the Armenian Philosophical Society |
| 1993-96 | Honorary President of the Armenian National Academy of Sciences |
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| Chairman or Member of Scientific Councils and Committees |
| 1944-46 | Chairman of the Astronomical Commission of the USSR Academy of Sciences |
| 1947-72 | Member of the Committee on Lenin and USSR State prizes in the field of science and engineering |
| 1947-96 | Chairman of the Administrative Board of the "Knowledge" society of the Armenian SSR |
| 1952-64 | Chairman of the Commission on Cosmogony of the USSR Acad. Sci. |
| 1955 | Member of the Council on the coordination of works of Academies of Sciences of the Union Republics |
| 1955-88 | Member of the Presidium of the USSR Academy of Sciences |
| 1956 | Member of the Committee on Lenin prizes |
| 1966 | Member of the Executive Committee of the International Council of Scientific Unions (ICSU) |
| 1970- | Chairman of the Committee of the Armenian SSR State prizes in the field of science and engineering |
| 1974-87 | Chairman of the United Scientific Council on Astronomy of the USSR Academy of Sciences |
| 1977-96 | Chairman of the Specialized Council for Theses Defense at BAO |
| 1987 | Councilor of the Armenian Philosophical Academy |
| 1994-96 | Councilor of the Russian Academy of Sciences |
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| Editor-in-Chief, Chairman or Member of Editorial Boards and Councils |
| 1944-59 | Editor-in-Chief of the journal “Doklady Arm. SSR Acad. Sci.” (“Reports of the Arm. SSR Academy of Sciences”) |
| 1944-79 | Member of the Editorial Board of the “Astronomicheski Zhournal” (“Soviet Astronomy”, “Astronomy Reports”) |
| 1946-85 | Editor-in-Chief of the “Communications of the Byurakan Observatory” |
| 1947-56 | Chairman of the Editorial-Publishing Council of the Armenian SSR Academy of Sciences |
| 1965-87 | Editor-in-Chief of the newly founded journal “Astrofizika” (“Astrophysics”) |
| 1965-74 | Chairman of the Editorial Board of the first “Armenian Soviet Encyclopedia” |
| 1965-87 | Chairman of the Scientific-Publishing Council of the first “Armenian Soviet Encyclopedia” |
| 1976- | Member of the Editorial Board of the “Reports of the USSR Academy of Sciences” |
| 1981-91 | Member of the Editorial Board of the international journal “Vistas in Astronomy” (UK) |
| 1981- | Member of the Editorial Board of the journal “Science in the USSR” |
| 1988-90 | Chairman of the Editorial Board of the “Armenian Brief Encyclopedia” |
| 1988-95 | Chairman of the Scientific-Publishing Council of the “Armenian Brief Encyclopedia” |
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