Chollian, (

Korean Korean may refer to: People and culture * Koreans, ethnic group originating in the Korean Peninsula * Korean cuisine * Korean culture * Korean language **Korean alphabet, known as Hangul or Chosŏn'gŭl **Korean dialects and the Jeju language ** ...

: 천리안, lit. ''Thousand Li View'', clairvoyance) also known as Communication, Ocean and Meteorological Satellite 1 (COMS-1), was a South Korean

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioiso ...

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 ind ...

, who used it for communication, oceanography, and meteorological observation. COMS-1 was constructed by

EADS Astrium Astrium was an aerospace manufacturer subsidiary of the European Aeronautic Defence and Space Company (EADS) that provided civil and military space systems and services from 2006 to 2013. In 2012, Astrium had a turnover of €5.8 billion and 18 ...

, 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 opposed to specially produced satellites. Bus- ...

, bringing together lessons learned from

Eurostar Eurostar is an international high-speed rail service connecting the United Kingdom with France, Belgium and the Netherlands. Most Eurostar trains travel through the Channel Tunnel between the United Kingdom and France, owned and operated sep ...

satellites and NASA-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, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two No ...

-defined spectrum, or the L/ S and

Ka band The Ka band (pronounced as either "kay-ay band" or "ka band") is a portion of the microwave part of the electromagnetic spectrum defined as frequencies in the range 26.5–40 gigahertz (GHz), i.e. wavelengths from slightly over one centime ...

s 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 1980 as the world's first commercial launch service provider. It undertakes the operation and marketing of the Ariane programme. The company offers a number of different launch vehicles: the heavy- ...

using an Ariane 5 ECA carrier rocket lifting off from

ELA-3 ELA-3 (french: Ensemble de Lancement Ariane 3, lit=Ariane Launch Complex 3), is a launch pad and associated facilities at the Centre Spatial Guyanais in French Guiana. ELA-3 is operated by Arianespace as part of the expendable launch system for ...

at the

Guiana Space Centre The Guiana Space Centre (french: links=no, Centre spatial guyanais; CSG), also called Europe's Spaceport, is a European spaceport to the northwest of Kourou in French Guiana, a region of France in South America. Kourou is located approximat ...

Kourou Kourou () is a commune in French Guiana, an overseas region and department of France in South America. Kourou is famous for being the location of the Guiana Space Centre, the main spaceport of France and the European Space Agency (ESA). It ...

French Guiana French Guiana ( or ; french: link=no, Guyane ; gcr, label=French Guianese Creole, Lagwiyann ) is an overseas departments and regions of France, overseas department/region and single territorial collectivity of France on the northern Atlantic ...

. 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 Western Asia. It covers the bulk of the Arabian Peninsula, and has a land area of about , making it the List of Asian countries by area, fifth-largest country in Asia ...

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 A geosynchronous transfer orbit or geostationary transfer orbit (GTO) is a type of geocentric orbit. Satellites that are destined for geosynchronous (GSO) or geostationary orbit (GEO) are (almost) always put into a GTO as an intermediate step ...

. It used an

apogee motor An apogee kick motor (AKM) is a rocket motor that is regularly employed on artificial satellites to provide the final impulse to change the trajectory from the transfer orbit into its final (most commonly circular) orbit. For a satellite la ...

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 orbit ...

. 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

{{Use British English, date=January 2014 Satellites of South Korea Spacecraft launched in 2010 Spacecraft decommissioned in 2020 Communications satellites in geostationary orbit Ariane commercial payloads