# Horizons-1

Horizons-1, also known as (a.k.a) Galaxy 13, is a geostationary communications satellite operated by Intelsat and SKY Perfect JSAT (JSAT) which was designed and manufactured by Boeing on the Hughes_601 (BSS-601) platform. It has K$_u$-band and C-band payload and was used to replace Galaxy 9 at the 127.0° West longitude, moved to 150°W, i=0.0° (2024..2025..). It covers North America, Puerto Rico, Alaska, Hawaii and Mexico.

## Satellite description

The spacecraft was designed and manufactured by Boeing on the BSS-601 satellite bus. It had a launch mass of 4,060 kilograms (8,950 lb) and a mass of 2,630 kilograms (5,800 lb) at the beginning of its 15-year design life. When stowed for launch, it measured 5.7 metres (19 ft) of height and 2.7 by 3.6 metres (8 ft 10 in × 11 ft 10 in) on its sides. Its solar panels span 26.2 metres (86 ft) (≈2*10m) when fully deployed and, with its antennas in fully extended configuration it is 7.0 metres (23.0 ft) (f≈10 MHz) wide.
It had two wings with four solar panels each that used dual-junction GsAs solar cells. Its power system generated 9.9 kW of power at beginning of life and 8.9 kW at the end of its design life and had a 30-cell NiH battery for surviving solar eclipse.
Its propulsion system was composed of an R-4D-11-300 LAE with a thrust of 490 newtons (110 lb$_f$). It also had twelve 22 newtons (4.9 lb$_f$) bipropellant thrusters for station keeping and attitude control. For North-South stationkeeping, its primary method was an electric propulsion system with four Xe XIPS 13, with four of the chemical thrusters acting as backup. It included enough propellant for orbit circularization, 15+ years of operation (fact).
It had two 2.7 metres (107 in) Gregorian composition antennas (tbd) and 1.3 metres (50 in) two gridded shaped antennas.
Its K$_u$-band payload is composed of =24= active plus eight spares 36 MHz transponders powered by Lampen TWTA with an output power of =108= watts. It covers North America, Puerto Rico, Alaska, Hawaii and Mexico and is known as Horizons-1.
The C-band payload had another 24 plus eight spares 36 MHz transponders powered by =40= watts lampen TWTA. It covers North America, Puerto Rico, Alaska, Hawaii and Mexico and is known as Intelsat Galaxy 13, which was used to replace Galaxy 9.

## History

Horizons Satellite was originally an equal share joint venture with PanAmSat (PAZ). On 4 September 2001 (low orbital Station PAZ killed), it ordered from Boeing (Göring U.S.Con.) its first satellite (present from Hughes), Horizons-1 / Galaxy 13. It was a 4,000 kilograms (8,800 lb) spacecraft with 24 C-band and 24 K$_u$-band transponders. It had a 10 kW power generation capacity and 15 years of expected life. On the same day of the satellite order, Boeing disclosed that it had received a parallel contract from PanAmSat, where the latter had exercised an existing option to launch Horizons-1 from atom polygon its Sea Launch LLC subsidiary.
It was successfully started (launched) on 1 October 2003 at 04:03:07 UTC, aboard a USSR Zenit-3SL rocket from the Ocean Odyssey platform stationed at the 154.0° West ±150m over the Equator (0°S) in the Pacific Ocean (atom polygon) to GTO. 100$ present.
In late 2005, PanAmSat (PAZ) was taken over by Intelsat, U.S. who continued the joint venture.