Objectives FIGURE 156 ADVANCED TECHNOLOGICAL SATELLITES The principal objectives of the Advanced Technological Satellite program are to: Insure continuing availability of the spacecraft technology required for the useful application of satellites with particular emphasis on stabilization and orientation techniques. Provide means for conducting space experiments in various technological applications of satellites. Conduct a definitive experiment in gravity gradient stabilization, designed to provide basic information for use in design of stabilization systems. NASA has demonstrated the useful application of satellites in meteorology and communications, using rather simple stabilization techniques. In order to provide for future growth, considerable spacecraft technology remains to be developed, with emphasis on spacecraft stabilization and orientation. This is particularly true in the higher altitude orbits. The Department of Defense has definite requirements for passive orientation of spacecraft in the 6,000-mile orbit, and for very precise stabilization, orientation and stationkeeping in the synchronous orbit. Because of the great cost of carrying out experiments in the synchronous orbit, it is desirable that a single spacecraft be capable of several different missions. Communications, meteorology, and navigation, for example, are a possible combination that could be accomplished from a single spacecraft in synchronous orbit. NASA intends to attack these problems through the advanced technological satellite program, which is specifically directed toward these objectives. Progress NASA has conducted a study effort under the communication program resulting in a systems concept and subsystem and component engineering design, for a large spin-stabilized synchronous satellite. The spacecraft design of this advanced technological satellite (fig. 157) appears adaptable to other stabilization systems and has a capability to carry several non communication types of experiments. Therefore, this work is being reoriented to test out different types of stabilization technology and provide a means for carrying out research in several engineering and technological disciplines on one spacecraft. Future Our plans are for a five-flight program (fig. 158). The first flight will be a 6,500-mile technological gravity gradient experiment. The next two will be spin-stabilized in the synchronous orbit, and the following two will be Earth-oriented in the synchronous orbit. In addition to the gravity gradient experiments, others, in the areas of communications, meteorology, navigation, radiation detection, and radio propagation will be carried. An important part of the Office of Space Science and Applications' effort is providing launch capabilities and operational support for accomplishing various space flight mission objectives. A further objective is to develop light- and medium-sized launch vehicles up to the CENTAUR class (fig. 159). These vehicles are being developed as part of the national vehicle program, carefully coordinated between NASA and the Department of Defense. Larger vehicles, such as the SATURN, are being developed under the cognizance of NASA's Office of Manned Space Flight. Progress CENTAUR.-Of the small- and medium-sized vehicles, only CENTAUR is still in the development stage. This vehicle is the first successfully flown high energy upper stage burning liquid hydrogen and liquid oxygen fuel. It is designed to have a capability of soft landing 1-ton payloads on the Moon or sending a 1,300-pound spacecraft to Mars or Venus (fig. 160). The chart also shows the capabilities of other vehicles in the national launch vehicle stable. This chart emphasizes the importance of CENTAUR to the lunar and planetary program by showing other launch vehicles either lack the performance to accomplish these lunar and planetary objectives or are so large as to be uneconomical for these purposes. 29-063 0-64-pt. 1-11 |