Global Collaboration

United around the human curiosity to understand our cosmic origins, an international coalition of scientists, engineers and technicians have come together from around the world to build the most powerful Earth observatory in history.

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile.

ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) in Taiwan and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

• Chile: Contributing with a world-class observation site

ALMA Partners: Sharing construction and operation costs

• ESO
• North América
• East Asia

Chile: Contributing with a world-class observation site

When a telescope needs to occupy an area that covers many square kilometers and must be located above most of the precipitable water vapor in the atmosphere, there aren’t many places left to choose from. The Chajnantor plateau in the northern Chilean Andes is one of these places, and presents ideal conditions for the operation of ALMA.

The ALMA site, under concession by the Chilean government for this important scientific use, is extremely high and dry. The site is also accessible and has the necessary infrastructure to keep the observatory stocked with water, food and fuel.

Chile is home to several world-class telescopes and Chileans also benefit from this. In exchange for occupying this exceptional place, ALMA contributes to the development of astronomy in Chile, promotes local initiatives and also supports its closest neighbors. More details on how ALMA contributes to Chile here: Benefits for the Community

ALMA Partners: Sharing construction and operation costs

ESO

ESO represents its 16 Member States: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Italy, Ireland, the Netherlands, Portugal, Spain, Sweden, Switzerland, Poland and United Kingdom.

ESO manages the contributions of numerous European universities and technology and research institutes that have supported ALMA with their technology and experience. ESO’s most significant contributions to ALMA include:

• 37.5 % of the total project budget
• 25 antennas with 12-meter diameters
• The ALMA antenna transporters (Otto and Lore)
• Water vapor radiometers for the antennas
• Road from ALMA’s main entrance to the Operations Support Facilities (OSF)
• OSF technical building
• Permanent power supply via generator turbines
• ALMA residence with dormitories for workers
• Receivers for Bands 7 and 9
• Front End power supply, cryostat and integration
• Back End components and optical-digital transmission system
• Tunable filter bank (TFB) cards for the Correlator of the 64 antennas
• Antenna platforms and interfaces in the ALMA Array Operations Site (AOS).
• Software
• Systems engineering
• Support for European users of ALMA through the European ALMA Regional Center (ARC)

North America

North America’s participation in ALMA is coordinated by the National Radio Astronomy Observatory (NRAO), on behalf of United States, Canada and Taiwan, and managed by Associated Universities, Inc. (AUI). Its work is financed by the National Science Foundation (NSF) of the United States in collaboration with the National Research Council (NRC) of Canada and the National Science Council (NSC) of Taiwan.

North America’s main contributions to the ALMA project include:

• 37.5 % of the total project budget
• 25 antennas with 12-meter diameters
• AOS Technical Building
• Roads to AOS
• Electrical distribution and AOS fiber optic cable
• Optic telescope for pointing
• 5 Switches (used for fast switching between the source observed and the sky, eliminating celestial noise)
• Front End support and handling vehicles
• Receivers for Bands 3 and 6
• Local assembly of oscillators and other components for all band receivers
• Front End components and integration
• Oscillators and other Back End components
• Correlator for 64 antennas
• Software
• Systems engineering
• Employer of the Joint ALMA Observatory local staff
• Support for North American and Chilean users of ALMA through the North American ALMA Regional Center (ARC)

East Asia

East Asia’s participation in ALMA is managed by the National Astronomical Observatory of Japan (NAOJ) on behalf of Japan, Taiwan and South Korea. Its work is funded by the National Institutes of Natural Sciences (NINS) of Japan in collaboration with the Academia Sinica (AS) in Taiwan, and the Korea Astronomy and Space Science Institute (KASI) of South Korea.

Through its association with ALMA in 2004, East Asia contributed powerful functionalities through the Atacama Compact Array (ACA), also known as the Morita Array. Thanks to this array, ALMA can observe celestial objects from a broader perspective. In fact, while the main antenna array concentrates its observations on the smaller details, the Morita Array provides a visualization of the larger structures in the same objects. Together they provide a complete image of the source studied.

Asia’s main contributions to ALMA include:

• 25 % of the total project budget
• Four 12-meter diameter antennas and 12 7-meter diameter antennas for ACA.
• ACA antenna platform interfaces
• Front End integration
• Receivers for Bands 4, 8 and 10
• ACA Back End components, including the optical-digital transmission system and oscillators
• ACA Correlator
• Software
• Systems engineering
• Support for East Asia users through the Asian ALMA Regional Center (ARC).

Likewise, East Asia has funded the manufacture of Front End and Back End components by other ALMA partners for the ACA antennas, including receiver cartridges identical to those from the antennas in the ALMA main array.