The European Space Agency (ESA; French: Agence spatiale européenne About this soundpronunciation (help·info), ASE; German: Europäische Weltraumorganisation) is an intergovernmental organisation of 22 member states dedicated to the exploration of space. Established in 1975 and headquartered in Paris, ESA has a worldwide staff of about 2,200 in 2018 and an annual budget of about €6.68 billion (~US$7.43 billion) in 2020.
ESA’s space flight programme includes human spaceflight (mainly through participation in the International Space Station program); the launch and operation of uncrewed exploration missions to other planets and the Moon; Earth observation, science and telecommunication; designing launch vehicles; and maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana. The main European launch vehicle Ariane 5 is operated through Arianespace with ESA sharing in the costs of launching and further developing this launch vehicle. The agency is also working with NASA to manufacture the Orion Spacecraft service module, that will fly on the Space Launch System.
The agency’s facilities are distributed among the following centres:
- ESA science missions are based at ESTEC in Noordwijk, Netherlands;
- Earth Observation missions at ESA Centre for Earth Observation in Frascati, Italy;
- ESA Mission Control (ESOC) is in Darmstadt, Germany;
- the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany;
- the European Centre for Space Applications and Telecommunications (ECSAT), a research institute created in 2009, is located in Harwell, England;
- and the European Space Astronomy Centre (ESAC) is located in Villanueva de la Cañada, Madrid, Spain.
The European Space Agency Science Programme is a long-term programme of space science and space exploration missions.
After World War II, many European scientists left Western Europe in order to work with the United States. Although the 1950s boom made it possible for Western European countries to invest in research and specifically in space-related activities, Western European scientists realised solely national projects would not be able to compete with the two main superpowers. In 1958, only months after the Sputnik shock, Edoardo Amaldi (Italy) and Pierre Auger (France), two prominent members of the Western European scientific community, met to discuss the foundation of a common Western European space agency. The meeting was attended by scientific representatives from eight countries, including Harrie Massey (United Kingdom).
The Western European nations decided to have two agencies: one concerned with developing a launch system, ELDO (European Launch Development Organization), and the other the precursor of the European Space Agency, ESRO (European Space Research Organisation). The latter was established on 20 March 1964 by an agreement signed on 14 June 1962. From 1968 to 1972, ESRO launched seven research satellites.
ESA in its current form was founded with the ESA Convention in 1975, when ESRO was merged with ELDO. ESA had ten founding member states: Belgium, Denmark, France, West Germany, Italy, the Netherlands, Spain, Sweden, Switzerland, and the United Kingdom. These signed the ESA Convention in 1975 and deposited the instruments of ratification by 1980, when the convention came into force. During this interval the agency functioned in a de facto fashion. ESA launched its first major scientific mission in 1975, Cos-B, a space probe monitoring gamma-ray emissions in the universe, which was first worked on by ESRO.