Chollian 2A (GEO-KOMPSAT 2A) final inspection
Mission typeCommunication
COSPAR ID2010-032A Edit this at Wikidata
SATCAT no.36744
Mission durationPlanned: 7 years
Final: 9 years
Spacecraft properties
ManufacturerEADS Astrium
Launch mass2,460 kilograms (5,420 lb)
Power2.5 kilowatts
Start of mission
Launch date26 June 2010, 21:41 (2010-06-26UTC21:41Z) UTC
RocketAriane 5 ECA
Launch siteKourou ELA-3
End of mission
Deactivated31 March 2020, 23:59 (2020-04-01UTC00:00) UTC
Orbital parameters
Reference systemGeocentric
Longitude128.2° East
Perigee altitude35,791 kilometres (22,239 mi)[1]
Apogee altitude35,795 kilometres (22,242 mi)[1]
Inclination0.03 degrees[1]
Period1436.13 minutes[1]
Epoch23 January 2015, 17:05:20 UTC[1]

Chollian, (Korean천리안; lit. Thousand Li View; clairvoyance)[2] also known as Communication, Ocean and Meteorological Satellite 1[3] (COMS-1), was a South Korean satellite which was launched on 26 June 2010 and began operations on 1 April 2011. It was operated by the Korea Aerospace Research Institute, who used it for communication, oceanography, and meteorological observation.

COMS-1 was constructed by EADS Astrium, and was based on the Eurostar-3000S satellite bus, bringing together lessons learned from Eurostar satellites and NASA-made GOES satellites respectively. It had a mass of 2,460 kilograms (5,420 lb), and carried transponders broadcasting in the D/E and K bands of the NATO-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.[4]

COMS-1 was launched by Arianespace using an Ariane 5 ECA carrier rocket lifting off from ELA-3 at the Guiana Space Centre in Kourou, French Guiana. The first launch attempt occurred on 23 June 2010; the launch was scrubbed due to a problem with one of the rocket's subsystems.[5] A subsequent attempt on 24 June was also scrubbed, due to a problem with the pressurisation of the rocket's fuel tanks.[6] The launch occurred at 21:41 UTC on 26 June 2010.[6][7] The Saudi Arabian 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.[8]

Following launch, COMS-1 separated into a geosynchronous transfer orbit. It used an apogee motor to raise itself into geosynchronous orbit. It then underwent testing before beginning operations at a longitude of 128.2 degrees East on 1 April 2011.[9][10] Its mission was scheduled to last seven years,[4] though the satellite had a design life of ten years.[11]

COMS-1 was deactivated on 31 March 2020, following a two-year extension of its seven-year primary mission.[9]

As follow-up satellites to Chollian-1, Chollian-2A and Chollian-2B were launched in December 2018 and in February 2020 respectively.[12]


  1. ^ a b c d e "COMS 1 Satellite details 2010-032A NORAD 36744". N2YO. 23 January 2015. Retrieved 25 January 2015.
  2. ^ McDowell, Jonathan (28 June 2010). "Issue 629". Jonathan's Space Report. Archived from the original on 24 October 2010. Retrieved 29 June 2010.
  3. ^ "Space Programs in Korea" (PDF). Asia Pacific Space Activity Forum. December 2006. p. 18. Retrieved 26 June 2010.
  4. ^ a b Krebs, Gunter. "COMS 1". Gunter's Space Page. Retrieved 26 June 2010.
  5. ^ "Flight 195 – Arabsat-5A - COMS: Launch delayed". Arianespace. 23 June 2010. Retrieved 26 June 2010.
  6. ^ a b "Arianespace launch 195 – Arabsat-5A and COMS: Liftoff is set for Saturday, June 26, 2010". Arianespace. 26 June 2010. Retrieved 26 June 2010.
  7. ^ "Ariane 5 marks its 37th consecutive success by orbiting the Arabsat-5A and COMS satellites". Arianespace. 26 June 2010. Retrieved 28 August 2021.
  8. ^ "Ariane 5 Does The Heavy Lifting For Arabsat-5A and COMS". Satnews Daily. 21 June 2010. Archived from the original on 16 July 2011. Retrieved 23 June 2010.
  9. ^ a b "COMS Retirement Information". KMA. WMO. 5 February 2020. Archived from the original on December 18, 2023. Retrieved 28 August 2021.
  10. ^ "Satellite Launches for the Middle East and South Korea" (PDF). Arianespace. Archived from the original (PDF) on 4 July 2010. Retrieved 26 June 2010.
  11. ^ "COMS". EADS Astrium. Archived from the original on 15 July 2010. Retrieved 26 June 2010.
  12. ^ Sheldon, John (9 January 2020). "South Korea's Chollian-2B Environmental Satellite To Launch In February 2020". SpaceWatch.Global. Retrieved 28 August 2021.