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Small Spacecraft in Support of the Lunar Exploration Program

This paper analyses the ability of small, low cost spacecraft to deliver scientifically and technically useful payloads to lunar orbit and the lunar surface, in particular precursor mapping, infrastructure and in-situ resource utilization functions, that are necessary prior to human return as part of the US Vision for Space Exploration. It is based upon a technical study of the NASA-Ames Research Center’s Small Spacecraft. Following an overview of the generalized capabilities of small spacecraft in comparison to the objectives of the robotic lunar exploration program, the paper documents the mission planning (including trajectory, launch stack and timeline), and overall spacecraft design (including mass budget, structure, propulsion, thermal, electrical power, descent guidance, navigation and control, and telecommunications) for a lunar lander mission. The study shows that spacecraft subject to the constraints laid out, in particular within a budget of < $100 Million and which can be launched on one of the next generation affordable launch vehicles such as Falcon-1 or Minotaur-V, can deliver payloads of 5-50 kg to the lunar surface or 10-200kg payload to lunar orbit. The payloads carried would be capable of covering most of the functions of lunar missions that are needed prior to human arrival, as identified in NASA’s Lunar Robotic Architecture Study, with the exception of the bulk ISRU tasks of the ‘Lander Rover’ (In-situ Resource Utilization (ISRU)) mission. The key advantages of smaller spacecraft are reduced costs and schedules.