The Korean VLBI Network (KVN) is a
radio astronomy
Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The first detection of radio waves from an astronomical object was in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation comin ...
observatory located in
South Korea
South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korean Peninsula and sharing a land border with North Korea. Its western border is formed by the Yellow Sea, while its eas ...
. It comprises three 21-meter radio telescopes that function as an
interferometer, using the technique of
very-long-baseline interferometry
Very-long-baseline interferometry (VLBI) is a type of astronomical interferometer, astronomical interferometry used in radio astronomy. In VLBI a signal from an astronomical radio source, such as a quasar, is collected at multiple radio telesco ...
(VLBI).
Characteristics
The KVN has three main dishes, each of 21m diameter and at respective separations of 300–500 km. All three dishes are located on university campus. Two are on the Korean peninsula:
Yonsei University
Yonsei University (; ) is a private research university in Seoul, South Korea. As a member of the " SKY" universities, Yonsei University is deemed one of the three most prestigious institutions in the country. It is particularly respected in th ...
(KY) and
Ulsan University (KU), and the third is located on
Jeju Island on the campus of
Jeju International University (formerly Tamna University; KT). The KVN antennas are Cassegrain-types with alt-az mounts. Each telescope has a 21-m diameter main reflector with a focal length of 6.78 m. The main reflectors consist of 200 aluminum panels each with a manufacturing surface accuracy of 65 microns.
A fourth telescope, the existing 14m dish located at the
Taeduk Radio Astronomy Observatory, will be linked to the KVN in the future via optical fiber networks.
KVN focuses on millimeter-wavelength VLBI, and is designed to make simultaneous measurements at four different observing frequencies: 22, 43, 86, and 129 GHz. The telescopes can operate together with VLBI networks in Japan and China the East Asian VLBI Network (EAVN). The EAVN consists of 19 antennae with a maximum baseline of 5000 km operating at 22 GHz; it can also operate at 43 GHz using only 9 antennae. The first fringes for EAVN at 22 GHz were successfully detected in 2009.
The KVN has also successfully been used for real-time VLBI between Korea and Europe.
[http://www.kasi.re.kr/View.aspx?id=report&page=2&si=False&sn=False&ss=True&sc=False&keyword=&pagesize=20&uid=3645 ]
Key science
KVN studies the
formation
Formation may refer to:
Linguistics
* Back-formation, the process of creating a new lexeme by removing or affixes
* Word formation, the creation of a new word by adding affixes
Mathematics and science
* Cave formation or speleothem, a secondar ...
and death processes of stars, the structure and dynamics of the
Milky Way
The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. ...
, the nature of
active galactic nuclei
An active galactic nucleus (AGN) is a compact region at the center of a galaxy that has a much-higher-than-normal luminosity over at least some portion of the electromagnetic spectrum with characteristics indicating that the luminosity is not prod ...
, and other astronomical topics. KVN is also used for
geodesy in detecting tectonic movements in the
Korean peninsula
Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic o ...
.
Visiting
The visitor's center for KVN is located at the Advanced Science & Technology Center on the campus of
Yonsei University
Yonsei University (; ) is a private research university in Seoul, South Korea. As a member of the " SKY" universities, Yonsei University is deemed one of the three most prestigious institutions in the country. It is particularly respected in th ...
in Seoul.
See also
*
List of radio telescopes
This is a list of radio telescopes – over one hundred – that are or have been used for radio astronomy. The list includes both single dishes and interferometric arrays. The list is sorted by region, then by name; unnamed telescopes are in r ...
*
Very-long-baseline interferometry
Very-long-baseline interferometry (VLBI) is a type of astronomical interferometer, astronomical interferometry used in radio astronomy. In VLBI a signal from an astronomical radio source, such as a quasar, is collected at multiple radio telesco ...
(VLBI)
References
External links
*
*
KASI website
{{Radio-astronomy
Astronomical observatories in South Korea
Interferometric telescopes
Radio telescopes