Capabilities, costs, and constraints of space transportation for planetary missions

Abstract

Launch vehicles currently fall into roughly four different performance categories: small, medium, intermediate, and large. In the past, most planetary missions relied on launch vehicles in the intermediate to large class, primarily because of heavy spacecraft or high launch energies. Recently, a shift has begun towards lower cost planetary missions that have more narrowly focused science objectives. Accordingly, the launch vehicle focus within NASA is shifting to medium performance class and below for new planetary missions, with an increase in planetary launch opportunities. A variety of U.S. and International launchers are available for this new category of missions, and their performance and capabilities are described in some detail. Included in the discussion are costs (U.S. only) and constraints associated with each launch vehicle. Some are currently in production, and many are just developmental at this point in time. Within NASA, there is a potential procurement for a new class of launch vehicle in between the small and medium classes. This category is termed medium-lite, and could become the primary niche for low-cost planetary missions in the future.