The ATS-6 Satellite

ATS-6 was the most complex and advanced communication satellite in NASA’s Applications Technology Satellite series.29 In 1966 NASA began launching a series of six such satellites manufactured by Fairchild to test and improve satellite com­munications. They were designed to carry out technological, meteorological, scien­tific, and communications research. The last of the series, ATS-6 was the largest, most complicated, and powerful of them all. It was a geosynchronous satellite— the orbital period for the 1,402-kilogram satellite around the globe matched the Earth’s 24-hour rotation so that the ATS-6 remained over the same spot on the earth. It was designed in such a way that it could be moved along the equator using its onboard thrusters to conduct space-based experiments in any region of the globe. In general it served as a powerful rebroadcasting station in space, capable

of transmitting signals directly to many small ground stations over a large area (figure 12.3). The prime objectives of ATS-6 missions involved demonstrating a 30-foot deployable antenna in synchronous orbit, providing a three-axis stabi­lized spacecraft with 0.1 degree pointing capability in all three axes, and provid­ing an oriented platform at synchronous altitude for advanced technological and scientific experiments. The SITE was made possible when all of these objectives were achieved.30ATS-6 thus represented the kind of satellite system appropriate for communications within many developing countries, where most of the population lived dispersed in rural areas, rather than in large population centers.31 ATS-6 was launched on May 30, 1974, and it carried approximately 15 scientific experiments in the field of communication, meteorology, and spacecraft stabilization.