spacecraft body, facing the antenna reflector, and linked to the antenna and the solar panels masts by a carbon-fiber reinforced plastic (CFRP) truss. The solar panels were rigidly mounted on two deployable masts. They were of hemi-cylinder shape, thus providing a relatively constant power (595 W beginning of life). Electric power was supplied during eclipses by two Nickel cadmium batteries of 15-A·h capacity, powering a regulated 30.5-V bus. The satellite dimensions in orbit were width by height. This deployable antenna parabola was designed and developed by Lockheed Missiles and Space Company (LMSC), now Lockheed Martin, under subcontract to Fairchild Aerospace, after several years of small study contracts at LMSC. The program manager at LMSC was GKC (Colin) Campbell. The deployment of the reflector was initiated by pyrotechnically operated SQUIB cable cutters. Deployment time was on the order of 2.5 seconds producing of torque at the spacecraft interface. The reflector surface was designed for optimal operation at S-Band frequencies. It weighed at launch and stowed into a toroidal volume (doughnut shaped) approximately in diameter and thick. Three models were fabricated, the STM or structural test model, the F reflector and the G reflector. The STM was destroyed by Fairchild shortly after the program was finished and the F model was launched with the spacecraft in 1972. The G model sat unprotected in the Farchild parking lot for several years before it was donated to the Smithsonian. Bill Wade, the assistant program manager and test manager on the program supported The Smithsonian in the restoration by providing a complete set of drawings and specifications and visited the Silver Hill facility to provide technical guidance. At the time of launch it was the largest parabolic surface launched into orbit. Three-axis stabilisation ATS-6 has been the first geostationary satellite with three-axis stabilization and pointing., This subsystem was capable of a highly accurate pointing (better than 0.1° through the inertial measurement units, down to 0.002° by using a radio-frequency interferometer.). Furthermore, the satellite was able to follow low earth orbit satellites through slewing, by tracking the low earth-orbit satellite through an S-band RF sensing. The system was also able to perform orbitography of the tracked satellite, and was a precursor to the operational system TDRSS. This highly advanced (for the time) pointing subsystem used earth and sun sensors, a star tracker pointed to the pole star, Polaris, and three inertial sensors. The sensor measurements were