
COAST, the Cambridge Optical Aperture Synthesis Telescope, is a multi-element optical
astronomical interferometer with baselines of up to 100 metres, which uses
aperture synthesis
Aperture synthesis or synthesis imaging is a type of interferometry that mixes signals from a collection of telescopes to produce images having the same angular resolution as an instrument the size of the entire collection. At each separation and ...
to observe stars with
angular resolution
Angular resolution describes the ability of any image-forming device such as an Optical telescope, optical or radio telescope, a microscope, a camera, or an Human eye, eye, to distinguish small details of an object, thereby making it a major det ...
as high as one thousandth of one
arcsecond
A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of one degree. Since one degree is of a turn (or complete rotation), one minute of arc is of a turn. The na ...
(producing much higher resolution images than individual telescopes, including the
Hubble Space Telescope
The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most ver ...
). The principal limitation is that COAST can only image bright
star
A star is an astronomical object comprising a luminous spheroid of plasma held together by its gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night, but their immense distances from Earth make ...
s.
COAST was the first long-baseline interferometer to obtain high-resolution images of the surfaces of stars other than Sun (although the surfaces of other stars had previously been imaged at lower resolution using
aperture masking interferometry on the
William Herschel Telescope
The William Herschel Telescope (WHT) is a optical/near-infrared reflecting telescope located at the Roque de los Muchachos Observatory on the island of La Palma in the Canary Islands, Spain. The telescope, which is named after William Herschel, ...
).
The COAST array was conceived by
John E. Baldwin and is operated by the
Cavendish Astrophysics Group
The Cavendish Astrophysics Group (formerly the Radio Astronomy Group) is based at the Cavendish Laboratory at the University of Cambridge. The group operates all of the telescopes at the Mullard Radio Astronomy Observatory except for the 32m MERL ...
. It is situated at the
Mullard Radio Astronomy Observatory
The Mullard Radio Astronomy Observatory (MRAO) is located near Cambridge, UK and is home to a number of the largest and most advanced aperture synthesis radio telescopes in the world, including the One-Mile Telescope, 5-km Ryle Telescope, a ...
in
Cambridgeshire
Cambridgeshire (abbreviated Cambs.) is a Counties of England, county in the East of England, bordering Lincolnshire to the north, Norfolk to the north-east, Suffolk to the east, Essex and Hertfordshire to the south, and Bedfordshire and North ...
,
England
England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe ...
.
See also
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List of observatories
This is a list of astronomical observatories ordered by name, along with initial dates of operation (where an accurate date is available) and location. The list also includes a final year of operation for many observatories that are no longer in ...
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List of telescope types
The following are lists of devices categorized as types of telescopes or devices associated with telescopes. They are broken into major classifications with many variations due to professional, amateur, and commercial sub-types. Telescopes can be ...
References
External links
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Optical telescopes
Interferometric telescopes
Cavendish Laboratory
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