Design of the Thermal Control System for the Space Technology 5 Microsatellite

The New Millennium Program’s (NMP) Space Technology 5 (ST-5) Project, currently in Phase B of the design process, is slated to launch three 20-kg class spin stabilized microsatellites in late 2003. The proposed orbit is highly elliptical and could result in an earth shadow eclipse of almost 2 hours. Although ST-5’s maximum eclipse is only 2 hours, future missions could involve eclipses as long as 8 hours. As spacecraft size, mass, and available resources decrease and eclipse duration increases, thermal engineers will be challenged to design simple but robust thermal control systems that meet temperature requirements for all phases of the mission. In addition, future similar missions may involve large “fleets” of such small spacecraft, which, for cost and I&T reasons, must be almost identical in design. Such spacecraft will require a generic but robust thermal control design that is suitable for a wide variety of thermal environments. This paper presents the results of a study of three design concepts and preliminary analysis of the design selected for ST-5.