The Swedish-ESO Submillimetre Telescope (SEST) is a 15-metre diameter

radio telescope A radio telescope is a specialized antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the radio frequency ...

. It was originally located at the

La Silla Observatory La Silla Observatory is an astronomy, astronomical observatory in Chile with three telescopes built and operated by the European Southern Observatory (ESO). Several other telescopes are located at the site and are partly maintained by ESO. The obse ...

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...

, and will be moved to Africa and repurposed as the Africa Millimetre Telescope.

La Silla Observatory, Chile

The telescope was built in 1987 as a combined project between

ESO The European Organisation for Astronomical Research in the Southern Hemisphere, commonly referred to as the European Southern Observatory (ESO), is an intergovernmental research organisation made up of 16 member states for ground-based ast ...

and

Onsala Space Observatory Onsala Space Observatory (OSO), the Swedish National Facility for Radio Astronomy, provides scientists with equipment to study the Earth and the rest of the Universe. The observatory operates two radio telescopes in Onsala, 45 km south of Got ...

, with contributions from Finland and Australia. It was then the only large telescope for

submillimetre astronomy Submillimetre astronomy or submillimeter astronomy (see spelling differences) is the branch of observational astronomy that is conducted at submillimetre wavelengths (i.e., terahertz radiation) of the electromagnetic spectrum. Astronomers plac ...

in the southern hemisphere. It was decommissioned in 2003. The telescope was used for single-dish observations of a wide range of

astronomical object An astronomical object, celestial object, stellar object or heavenly body is a naturally occurring physical entity, association, or structure that exists in the observable universe. In astronomy, the terms ''object'' and ''body'' are often us ...

s, especially the

Galactic Center The Galactic Center or Galactic Centre is the rotational center, the barycenter, of the Milky Way galaxy. Its central massive object is a supermassive black hole of about 4 million solar masses, which is called Sagittarius A*, a compact rad ...

and the

Magellanic Clouds The Magellanic Clouds (''Magellanic system'' or ''Nubeculae Magellani'') are two irregular dwarf galaxies in the southern celestial hemisphere. Orbiting the Milky Way galaxy, these satellite galaxies are members of the Local Group. Because both ...

and for

interferometric Interferometry is a technique which uses the ''interference'' of superimposed waves to extract information. Interferometry typically uses electromagnetic waves and is an important investigative technique in the fields of astronomy, fiber op ...

observations at millimetre wavelengths. In 1995 observations made with SEST showed that the

Boomerang Nebula The Boomerang Nebula is a protoplanetary nebula located 5,000 light-years away from Earth in the constellation Centaurus. It is also known as the Bow Tie Nebula and catalogued as LEDA 3074547. The nebula's temperature is measured at making it ...

is the coldest known location in the

universe The universe is all of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy. The Big Bang theory is the prevailing cosmological description of the development of the universe. Acc ...

, with a temperature lower than the

background radiation Background radiation is a measure of the level of ionizing radiation present in the environment at a particular location which is not due to deliberate introduction of radiation sources. Background radiation originates from a variety of sources ...

Africa Millimetre Telescope

In 2022 it was announced that the telescope will be relocated on or near to

Table Mountain Table Mountain ( naq, Huriǂoaxa, lit= sea-emerging; af, Tafelberg) is a flat-topped mountain forming a prominent landmark overlooking the city of Cape Town in South Africa. It is a significant tourist attraction, with many visitors using the ...

, within the Gamsberg Nature Reserve in Namibia, with the exact location to be decided. It will be the first millimetre radio telescope in mainland Africa. The relocation, refurbishment, and modifications, as well as operations and outreach activities, will cost $25 million. The project started in 2022, and will last for five years. The telescope will operate as part of the

Event Horizon Telescope The Event Horizon Telescope (EHT) is a large telescope array consisting of a global network of radio telescopes. The EHT project combines data from several very-long-baseline interferometry (VLBI) stations around Earth, which form a combined arr ...

for 20% of its time. The project is a collaboration between the

University of Namibia The University of Namibia (UNAM) is a multi-campus public research university in Namibia, as well as the largest university in the country. It was established by an act of Parliament on 31 August 1992. Background UNAM comprises the follow ...

Windhoek Windhoek (, , ) is the capital and largest city of Namibia. It is located in central Namibia in the Khomas Highland plateau area, at around above sea level, almost exactly at the country's geographical centre. The population of Windhoek in 20 ...

, and

Radboud University Nijmegen Radboud University (abbreviated as RU, nl, Radboud Universiteit , formerly ''Katholieke Universiteit Nijmegen'') is a public research university located in Nijmegen, the Netherlands. The university bears the name of Saint Radboud, a 9th century D ...

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

, and also involves the

European Southern Observatory The European Organisation for Astronomical Research in the Southern Hemisphere, commonly referred to as the European Southern Observatory (ESO), is an intergovernmental organization, intergovernmental research organisation made up of 16 mem ...

and the Netherlands Research School for Astronomy (NOVA). It follows from a proposal to construct such a telescope in Africa in 2017.

Gallery

File:Hunting stars.jpg, SEST and Orion with his famous

belt Belt may refer to: Apparel * Belt (clothing), a leather or fabric band worn around the waist * Championship belt, a type of trophy used primarily in combat sports * Colored belts, such as a black belt or red belt, worn by martial arts practit ...

and

sword A sword is an edged, bladed weapon intended for manual cutting or thrusting. Its blade, longer than a knife or dagger, is attached to a hilt and can be straight or curved. A thrusting sword tends to have a straighter blade with a pointed ti ...

. File:La Silla Dawn Kisses the Milky Way.jpg, SEST dish measures 15 metres across. It was decommissioned in 2003. File:Dizzying Star Trails over SEST.jpg, Sky filled with

star trail A star trail is a type of photograph that uses long exposure times to capture '' diurnal circles'', the apparent motion of stars in the night sky due to Earth's rotation. A star-trail photograph shows individual stars as streaks across the i ...

s, a result of the camera's long exposure time. File:Observatoire de la Silla - Swedish-ESO Submillimetre Telescope.JPG, SEST with the

ESO 3.6 m Telescope The ESO 3.6 m Telescope is an optical reflecting telescope run by the European Southern Observatory at La Silla Observatory, Chile since 1977, with a clear aperture of about and area. The telescopes uses the HARPS instrument and has discovered ...

in the background

References

{{Reflist, refs= {{cite journal , last1=Wild , first1=Sarah , title=Major African radio telescope will help to image black holes , url=https://www.nature.com/articles/d41586-022-00205-4 , access-date=4 February 2022 , journal=Nature , date=4 February 2022 , volume=602 , issue=7897 , page=375 , language=en , doi=10.1038/d41586-022-00205-4 {{Cite Q, Q62398296 European Southern Observatory Radio telescopes Submillimetre telescopes 1987 establishments in Chile Buildings and structures in Hardap Region Astronomical observatories in Namibia

La Silla Observatory, Chile

Africa Millimetre Telescope

Gallery

See also

References