Geostationary communications satellites, once launched and in orbit, need to operate for years with high reliability. To achieve such performance, satellites undergo a rigorous process of testing during manufacture to ensure that each spacecraft component and system can withstand the rigors of launch and the extremes of the space environment.
This artifact--a Horizon Sensor Target Assembly--is a component of the satellite check-out station for Intelsat VIIIA (805) communications spacecraft, built by Lockheed Martin and launched in 1998. The checkout station was a suite of testing devices used to simulate and assess a broad range of spacecraft functions after final assembly. Technicians tested the satellite at the factory and then again at the launch site.
The Horizon Sensor Target Assembly was designed to simulate one such function: The performance of Earth horizon sensors, which helped the spacecraft maintain its orientation during travel to geostationary orbit and then in routine operation. The sensor test assemblies were mounted to the satellite and the discs rotated to simulate the presence of the Earth's horizon.
This artifact was donated by Lockheed Martin to the Museum in 1998.
Gift of Lockheed Martin