AN OVERVIEW OF NASA PROJECTED MISSION REQUIREMENTS FOR SPACE NUCLEAR SYSTEMS

NASA has completed a series of top-down reviews of its missions and sp ace technology programs with a strong focus on missions which can be d one faster, at less cost and with better performance. In addition, NAS A has created a new office, the Office of Advanced Concepts and Techno logy, with a strong customer focus on technology. As a result of these reviews a number of exciting options are being considered for space n uclear systems. Of course, the near-term ongoing NASA space nuclear pr ogram is the Cassini mission to Saturn which will use three radioisoto pe thermoelectric generators (RTGs). Beyond that NASA is studying a Pl uto Fast Flyby mission which will challenge the space power community to produce a low-mass RTG. Another candidate RTG mission is the Mars E nvironmental Survey (MESUR) mission to emplace a number of probes on t he surface of Mars to obtain a more global survey of the planet than w as accomplished with the two Viking Landers. Looking toward the 21st c entury there are a number of exciting planetary missions, such as the Jupiter Grand Tour, Outer Planet Orbiters/Probes, comet/asteroid rende zvous/sample return, which are enabled or greatly enhanced by nuclear reactor power coupled with electric propulsion.