Horizons-2

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Horizons-2
Mission type Communications
Operator Intelsat/JSAT
COSPAR ID 2007-063B
SATCAT № 32388
Mission duration 15 years
Spacecraft properties
Bus Star-2
Manufacturer Orbital Sciences
Launch mass 2,350 kilograms (5,180 lb)
Start of mission
Launch date 21 December 2007, 21:41:55 (2007-12-21UTC21:41:55Z) UTC
Rocket Ariane 5GS
Launch site Kourou ELA-3
Contractor Arianespace
Orbital parameters
Reference system Geocentric
Regime Geostationary
Longitude 74° west (2008-2011)
84.9° east (2011—)
Perigee 35,784.2 kilometres (22,235.3 mi)
Apogee 35,803.5 kilometres (22,247.3 mi)
Inclination 0.0 degrees[1]
Period 1,436.1 minutes
Transponders
Band 20 Ku-band
Coverage area Continental United States
Caribbean
Canada
EIRP 3.5 kilowatts (minimum EOL)

Horizons-2 is a Ku band communications satellite owned by Horizons Satellite LLC, a joint venture between JSAT and Intelsat.[2] Its orbital slot is located at 74° west longitude.

Launch[edit]

Horizons-2 was launched from the Guiana Space Centre — along with the Rascom-QAF 1 spacecraft — aboard an Arianespace Ariane 5-GS. Launch occurred at 21:42 GMT on 21 December 2007.[3]

Platform and payload[edit]

Horizons-2 was built by Orbital Sciences Corporation based on its STAR Bus satellite platform, which will generate 3.5 kilowatts of payload power by means of two solar arrays, each equipped with three panels of UJT gallium arsenide cells. The solar arrays charge two lithium ion batteries with capacities of at least 3,850 watt-hours.

The spacecraft is 3-axis stabilized, with a zero momentum system. Hydrazine-fuelled monopropellant thrusters are used for stationkeeping, with an IHI BT-4 bipropellant engine used for insertion into geostationary orbit. It has a design life of 15 years, however it is fuelled for at least 16 years of operations. Its payload consists of 20 Ku-band transponders broadcasting through two 2.3-meter (7.5 ft) dual gridded shaped reflectors.
[4] It has 16 active transponders with 22-for-16 redundant 85 W TWTAs and four active transponders with 6-for-4 redundant 150 W TWTAs. The satellite will provide service to the continental United States, the Caribbean and parts of Canada.

References[edit]