International Astronomical Union

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International Astronomical Union (IAU)
Union astronomique internationale (UAI)
IAU logo.svg
Members of International Astronomical Union.svg
National members from 82 countries as of 2020
  Member states
  Member with interim status
  Observer states
  Suspended states
Formation28 July 1919;102 years ago (1919-07-28)
Headquarters Paris, France
82 national members [1]
13,701 individual members [2]
Ewine van Dishoeck
Maria Teresa Lago

The International Astronomical Union (IAU; French : Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and development through global cooperation. [3] It was founded in 1919 and is based in Paris, France.


The IAU is composed of individual members, who include both professional astronomers and junior scientists, and national members, such as professional associations, national societies, or academic institutions. Individual members are organised into divisions, committees, and working groups centered on particular subdisciplines, subjects, or initiatives. As of 2018, the Union had over 13,700 individual members, spanning 90 countries, and 82 national members. [4]

Among the key activities of the IAU is serving as a forum for scientific conferences. It sponsors nine annual symposia and holds a triannual General Assembly that sets policy and includes various scientific meetings. The Union is best known for being the leading authority in assigning official names and designations to astronomical objects, and for setting uniform definitions for astronomical principles. It also coordinates with national and international partners, such as UNESCO, to fulfill its mission.

The IAU is a member of the International Science Council (ISC), which is composed of international scholarly and scientific institutions and national academies of sciences..


The International Astronomical Union is an international association of professional astronomers, at the PhD level and beyond, active in professional research and education in astronomy. [5] Among other activities, it acts as the recognized authority for assigning designations and names to celestial bodies (stars, planets, asteroids, etc.) and any surface features on them. [6]

The IAU is a member of the International Science Council (ISC). Its main objective is to promote and safeguard the science of astronomy in all its aspects through international cooperation. The IAU maintains friendly relations with organizations that include amateur astronomers in their membership. The IAU has its head office on the second floor of the Institut d'Astrophysique de Paris in the 14th arrondissement of Paris. [7]

This organisation has many working groups. For example, the Working Group for Planetary System Nomenclature (WGPSN), which maintains the astronomical naming conventions and planetary nomenclature for planetary bodies, and the Working Group on Star Names (WGSN), which catalogues and standardizes proper names for stars. The IAU is also responsible for the system of astronomical telegrams which are produced and distributed on its behalf by the Central Bureau for Astronomical Telegrams. The Minor Planet Center also operates under the IAU, and is a "clearinghouse" for all non-planetary or non-moon bodies in the Solar System. [8]


The IAU was founded on 28 July 1919, at the Constitutive Assembly of the International Research Council (now the International Science Council) held in Brussels, Belgium. [9] [10] Two subsidiaries of the IAU were also created at this assembly: the International Time Commission seated at the International Time Bureau in Paris, France, and the International Central Bureau of Astronomical Telegrams initially seated in Copenhagen, Denmark. [9]

The seven initial member states were Belgium, Canada, France, Great Britain, Greece, Japan, and the United States, soon to be followed by Italy and Mexico. [9] The first executive committee consisted of Benjamin Baillaud (President, France), Alfred Fowler (General Secretary, UK), and four vice presidents: William Campbell (USA), Frank Dyson (UK), Georges Lecointe (Belgium), and Annibale Riccò (Italy). [9] Thirty-two Commissions (referred to initially as Standing Committees) were appointed at the Brussels meeting and focused on topics ranging from relativity to minor planets. The reports of these 32 Commissions formed the main substance of the first General Assembly, which took place in Rome, Italy, 2–10 May 1922.

By the end of the first General Assembly, ten additional nations (Australia, Brazil, Czecho-Slovakia, Denmark, the Netherlands, Norway, Poland, Romania, South Africa, and Spain) had joined the Union, bringing the total membership to 19 countries. Although the Union was officially formed eight months after the end of World War I, international collaboration in astronomy had been strong in the pre-war era (e.g., the Astronomische Gesellschaft Katalog projects since 1868, the Astrographic Catalogue since 1887, and the International Union for Solar research since 1904). [9]

The first 50 years of the Union's history are well documented. [9] [10] Subsequent history is recorded in the form of reminiscences of past IAU Presidents and General Secretaries. Twelve of the fourteen past General Secretaries in the period 1964-2006 contributed their recollections of the Union's history in IAU Information Bulletin No. 100. [11] Six past IAU Presidents in the period 1976–2003 also contributed their recollections in IAU Information Bulletin No. 104. [12]


The IAU includes member organizations from 82 countries (designated as national members) IAU National Members.svg
The IAU includes member organizations from 82 countries (designated as national members)

As of 1 August 2019, the IAU has a total of 13,701 individual members, who are professional astronomers from 102 countries worldwide; 81.7% of individual members are male, while 18.3% are female. [2]

Membership also includes 82 national members, professional astronomical communities representing their country's affiliation with the IAU. National members include the Australian Academy of Science, the Chinese Astronomical Society, the French Academy of Sciences, the Indian National Science Academy, the National Academies (United States), the National Research Foundation of South Africa, the National Scientific and Technical Research Council (Argentina), KACST (Saudi Arabia), the Council of German Observatories, the Royal Astronomical Society (United Kingdom), the Royal Astronomical Society of New Zealand, the Royal Swedish Academy of Sciences, the Russian Academy of Sciences, and the Science Council of Japan, among many others. [1]

The sovereign body of the IAU is its General Assembly, which comprises all members. The Assembly determines IAU policy, approves the Statutes and By-Laws of the Union (and amendments proposed thereto) and elects various committees.

The right to vote on matters brought before the Assembly varies according to the type of business under discussion. The Statutes consider such business to be divided into two categories:

On budget matters (which fall into the second category), votes are weighted according to the relative subscription levels of the national members. A second category vote requires a turnout of at least two-thirds of national members to be valid. An absolute majority is sufficient for approval in any vote, except for Statute revision which requires a two-thirds majority. An equality of votes is resolved by the vote of the President of the Union.

List of national members

Terminated national members

General Assemblies

Since 1922, the IAU General Assembly meets every three years, except for the period between 1938 and 1948, due to World War II. After a Polish request in 1967, and by a controversial decision [13] of the then President of the IAU, an Extraordinary IAU General Assembly was held in September 1973 in Warsaw, Poland, [14] to commemorate the 500th anniversary of the birth of Nicolaus Copernicus, soon after the regular 1973 GA had been held in Sydney, Australia.

Ist IAU General Assembly (1st)1922 Rome, Italy
IInd IAU General Assembly (2nd)1925 Cambridge, England, United Kingdom
IIIrd IAU General Assembly (3rd)1928 Leiden, Netherlands
IVth IAU General Assembly (4th)1932 Cambridge, Massachusetts, United States
Vth IAU General Assembly (5th)1935 Paris, France
VIth IAU General Assembly (6th)1938 Stockholm, Sweden
VIIth IAU General Assembly (7th)1948 Zürich, Switzerland
VIIIth IAU General Assembly (8th)1952 Rome, Italy
IXth IAU General Assembly (9th)1955 Dublin, Ireland
Xth IAU General Assembly (10th)1958 Moscow, Soviet Union
XIth IAU General Assembly (11th)1961 Berkeley, California, United States
XIIth IAU General Assembly (12th)1964 Hamburg, West Germany
XIIIth IAU General Assembly (13th)1967 Prague, Czechoslovakia
XIVth IAU General Assembly (14th)1970 Brighton, England, United Kingdom
XVth IAU General Assembly (15th)1973 Sydney, New South Wales, Australia
XVIth IAU General Assembly (16th)1976 Grenoble, France
XVIIth IAU General Assembly (17th)1979 Montreal, Quebec, Canada
XVIIIth IAU General Assembly (18th)1982 Patras, Greece
XIXth IAU General Assembly (19th)1985 New Delhi, India
XXth IAU General Assembly (20th)1988 Baltimore, Maryland, United States
XXIst IAU General Assembly (21st)1991 Buenos Aires, Argentina
XXIInd IAU General Assembly (22nd)1994 The Hague, Netherlands
XXIIIrd IAU General Assembly (23rd)1997 Kyoto, Kansai, Japan
XXIVth IAU General Assembly (24th)2000 Manchester, England, United Kingdom
XXVth IAU General Assembly (25th)2003 Sydney, New South Wales, Australia
XXVIth IAU General Assembly (26th)2006 Prague, Czech Republic
XXVIIth IAU General Assembly (27th)2009 Rio de Janeiro, Brazil
XXVIIIth IAU General Assembly (28th)2012 Beijing, China
XXIXth IAU General Assembly (29th)2015 Honolulu, Hawaii, United States
XXXth IAU General Assembly (30th)2018 Vienna, Austria
XXXIst IAU General Assembly (31st)2022 [15] Busan, South Korea

List of the presidents of the IAU

Sources. [16] [17]


Commission 46: Education in astronomy

Commission 46 is a Committee of the Executive Committee of the IAU, playing a special role in the discussion of astronomy development with governments and scientific academies. The IAU is affiliated with the International Council of Scientific Unions (ICSU), a non-governmental organization representing a global membership that includes both national scientific bodies and international scientific unions. They often encourage countries to become members of the IAU. The Commission further seeks to development, information or improvement of astronomical education. Part of Commission 46, is Teaching Astronomy for Development (TAD) program in countries where there is currently very little astronomical education. Another program is named the Galileo Teacher Training Program (GTTP), is a project of the International Year of Astronomy 2009, among which Hands-On Universe that will concentrate more resources on education activities for children and schools designed to advance sustainable global development. GTTP is also concerned with the effective use and transfer of astronomy education tools and resources into classroom science curricula. A strategic plan for the period 2010-2020 has been published. [18]


Cover picture of CAP Journal issue 19, March 2016. Cover picture of CAP Journal issue 19.jpg
Cover picture of CAP Journal issue 19, March 2016.

In 2004 the IAU contracted with the Cambridge University Press to publish the Proceedings of the International Astronomical Union. [20]

In 2007, the Communicating Astronomy with the Public Journal Working Group prepared a study assessing the feasibility of the Communicating Astronomy with the Public Journal (CAP Journal).[ citation needed ]

See also

Related Research Articles

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An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either observational or theoretical astronomy. Examples of topics or fields astronomers study include planetary science, solar astronomy, the origin or evolution of stars, or the formation of galaxies. Related but distinct subjects are like physical cosmology, which studies the Universe as a whole.

Astronomical unit Mean distance between Earth and the Sun, common length reference in astronomy

The astronomical unit is a unit of length, roughly the distance from Earth to the Sun and equal to about 150 million kilometres or ~8 light minutes. The actual distance from Earth to the Sun varies by about 3% as Earth orbits the Sun, from a maximum (aphelion) to a minimum (perihelion) and back again once each year. The astronomical unit was originally conceived as the average of Earth's aphelion and perihelion; however, since 2012 it has been defined as exactly 149597870700 m.

In ancient times, only the Sun and Moon, a few stars, and the most easily visible planets had names. Over the last few hundred years, the number of identified astronomical objects has risen from hundreds to over a billion, and more are discovered every year. Astronomers need to be able to assign systematic designations to unambiguously identify all of these objects, and at the same time give names to the most interesting objects, and where relevant, features of those objects.

The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory.

David C. Jewitt British-American astronomer (born 1958)

David Clifford Jewitt is a British-American astronomer who studies the Solar System, especially its minor bodies. He is based at the University of California, Los Angeles, where he is a Member of the Institute for Geophysics and Planetary Physics, the Director of the Institute for Planets and Exoplanets, Professor of Astronomy in the Department of Physics and Astronomy and Professor of Astronomy in the Department of Earth, Planetary and Space Sciences. He is best known for being the first person to discover a body beyond Pluto and Charon in the Kuiper belt.

Bart Bok American astronomer and lecturer (1906–1983)

Bartholomeus Jan "Bart" Bok was a Dutch-American astronomer, teacher, and lecturer. He is best known for his work on the structure and evolution of the Milky Way galaxy, and for the discovery of Bok globules, which are small, densely dark clouds of interstellar gas and dust that can be seen silhouetted against brighter backgrounds. Bok suggested that these globules may be in the process of contracting, before forming into stars.

Definition of <i>planet</i> History of the word "planet" and its definition

The definition of planet, since the word was coined by the ancient Greeks, has included within its scope a wide range of celestial bodies. Greek astronomers employed the term asteres planetai, "wandering stars", for star-like objects which apparently moved over the sky. Over the millennia, the term has included a variety of different objects, from the Sun and the Moon to satellites and asteroids.

Krisztián Sárneczky

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International Year of Astronomy

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Dwarf planet Planetary-mass object

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Jean-Claude Pecker was a French astronomer, astrophysicist and author, member of the French Academy of Sciences and director of the Nice Observatory. He served as the secretary-general of the International Astronomical Union from 1964 to 1967. Pecker was the President of the Société astronomique de France (SAF), the French amateur astronomical society, from 1973–1976. He was awarded the Prix Jules Janssen by the French Astronomical Society in 1967. A minor planet is named after him. Pecker was a vocal opponent of astrology and pseudo-science and was the president of the Association française pour l'information scientifique (AFIS), a skeptical organisation which promotes scientific enquiry in the face of quackery and obscurantism.

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  1. 1 2 National Members
  2. 1 2 Geographical and Gender Distribution of Individual Members
  3. Teaching English Creatively, Routledge, 30 April 2015, pp. 17–26, doi:10.4324/9781315766904-8, ISBN   978-1-315-76690-4 , retrieved 2 July 2021
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  6. Overbye, Dennis (4 August 2014). "You Won't Meet the Beatles in Space - Plan to Liven Official Naming of Stars and Planets Hits Clunky Notes". The New York Times . Retrieved 11 October 2016.
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  12. IAU Information Bulletin No. 104, June 2009
  13. Gingerich, Owen (1999). "The Copernican Quinquecentennial and Its Predecessors: Historical Insights and National Agendas". Osiris. 14: 50–51. Bibcode:1999Osir...14...37G. doi:10.1086/649299. JSTOR   301960. S2CID   144982060.
  14. Extraordinary General Assembly
  15. "International Astronomical Union | IAU".
  16. "Past Executive Committee". International Astronomical Union. Retrieved 18 September 2018.
  17. Колчинский И. Г., Корсунь А. А., Родригес М. Г. (1977). Астрономы. Биографический справочник (in Russian). Киев: Наукова Думка.CS1 maint: multiple names: authors list (link)
  18. Astronomy for the Developing World, Building from the IYA 2009, Strategic Plan 2010-20
  19. "CAPjournal Rosetta Special Out Now" . Retrieved 28 March 2016.
  20. "Proceedings of the International Astronomical Union". Cambridge Journals Online. Cambridge University Press . Retrieved 1 September 2015.