Chollian, () also known as Communication, Ocean and Meteorological Satellite 1 (COMS-1), was a South Korean

satellite A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scient ...

which was launched on 26 June 2010 and began operations on 1 April 2011. It was operated by the

Korea Aerospace Research Institute The Korea Aerospace Research Institute (KARI; ), established in 1989, is the aeronautics and space agency of South Korea. Its main laboratories are located in Daejeon, in the Daedeok Science Town. KARI's vision is to continue building upon in ...

, who used it for communication,

oceanography Oceanography (), also known as oceanology, sea science, ocean science, and marine science, is the scientific study of the ocean, including its physics, chemistry, biology, and geology. It is an Earth science, which covers a wide range of to ...

, and meteorological observation. COMS-1 was constructed by EADS Astrium, and was based on the Eurostar-3000S

satellite bus A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held. Bus-derived satellites are less customized than specially-produced satelli ...

, bringing together lessons learned from

Eurostar Eurostar is an international high-speed rail service in Western Europe, connecting Belgium, France, Germany, the Netherlands and the United Kingdom. The service is operated by the Eurostar Group which was formed from the merger of Eurostar, ...

satellites and

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

-made GOES satellites respectively. It had a mass of , and carried

transponder In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend of ''transmitter'' and ''responder''. In air navigation or radio frequency identification, a flight trans ...

s broadcasting in the D/ E and K bands of the

NATO The North Atlantic Treaty Organization (NATO ; , OTAN), also called the North Atlantic Alliance, is an intergovernmental organization, intergovernmental Transnationalism, transnational military alliance of 32 Member states of NATO, member s ...

-defined spectrum, or the L/ S and Ka bands of the IEEE-defined spectrum respectively. Its single solar array generated a minimum of 2.5 kilowatts of power. COMS-1 was launched by

Arianespace Arianespace SA is a French company founded in March 1980 as the world's first commercial launch service provider. It operates two launch vehicles: Vega C, a Small-lift launch vehicle, small-lift rocket, and Ariane 6, a Medium-lift launch vehicl ...

using an

Ariane 5 ECA Ariane 5 is a retired European Heavy-lift launch vehicle, heavy-lift space launch vehicle operated by Arianespace for the European Space Agency (ESA). It was launched from the Guiana Space Centre (CSG) in French Guiana. It was used to deliver p ...

carrier rocket lifting off from

ELA-3 ELA-3 () is a launch complex at the Guiana Space Centre in French Guiana. The complex was first used in June 1996 in support of the now retired Ariane 5 Ariane 5 is a retired European heavy-lift space launch vehicle operated by Arianespac ...

at the

Guiana Space Centre The Guiana Space Centre (; CSG), also called Europe's Spaceport, is a spaceport to the northwest of Kourou in French Guiana, an Overseas departments and regions of France, overseas region of France in South America. Kourou is located approxim ...

in Kourou,

French Guiana French Guiana, or Guyane in French, is an Overseas departments and regions of France, overseas department and region of France located on the northern coast of South America in the Guianas and the West Indies. Bordered by Suriname to the west ...

. The first launch attempt occurred on 23 June 2010; the launch was scrubbed due to a problem with one of the rocket's subsystems. A subsequent attempt on 24 June was also scrubbed, due to a problem with the pressurisation of the rocket's fuel tanks. The launch occurred at 21:41 UTC on 26 June 2010. The

Saudi Arabia Saudi Arabia, officially the Kingdom of Saudi Arabia (KSA), is a country in West Asia. Located in the centre of the Middle East, it covers the bulk of the Arabian Peninsula and has a land area of about , making it the List of Asian countries ...

n Arabsat-5A satellite was launched by the same rocket, with a SYLDA adaptor being used to separate the spacecraft. Arabsat-5A was mounted atop the SYLDA, with COMS-1 underneath it. Following launch, COMS-1 separated into a geosynchronous transfer orbit. It used an apogee motor to raise itself into

geosynchronous orbit A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day). The synchronization of rotation and orbital ...

. It then underwent testing before beginning operations at a longitude of 128.2 degrees East on 1 April 2011. Its mission was scheduled to last seven years, though the satellite had a design life of ten years. COMS-1 was deactivated on 31 March 2020, following a two-year extension of its seven-year primary mission. As follow-up satellites to Chollian-1, Chollian-2A and Chollian-2B were launched in December 2018 and in February 2020 respectively.

References

{{Orbital launches in 2010 Weather satellites of South Korea Spacecraft launched in 2010 Spacecraft decommissioned in 2020 Communications satellites in geostationary orbit Ariane commercial payloads