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This paper uses surrogate models to reduce the computational cost associated with spacecraft mission design in three-body dynamical systems. Sampling-based least squares regression is used to project the system response onto a set of orthogonal bases, providing a representation of the ∆V required for rendezvous as a reduced-order surrogate model. Models are presented for mid-field rendezvous of spacecraft in orbits in the Earth-Moon circular restricted three-body problem, including a halo orbit about the Earth-Moon L 2 libration point (EML-2) and a distant retrograde orbit (DRO) about the Moon. In each case, the initial position of the spacecraft, the time of flight, and the separation between the chaser and the target vehicles are all considered as design inputs. The results show that sample sizes on the order of 10 2 are sufficient to produce accurate surrogates, with RMS errors reaching 0.2 m/s for the halo orbit and falling below 0.01 m/s for the DRO. A single function call to the resulting surrogate is up to two orders of magnitude faster than computing the same solution using full fidelity propagators. The expansion coefficients solved for in the surrogates are then used to conduct a global sensitivity analysis of the ∆V on each of the input parameters, which identifies the separation between the spacecraft as the primary contributor to the ∆V cost. Finally, the models are demonstrated to be useful for cheap evaluation of the cost function in constrained optimization problems seeking to minimize the ∆V required for rendezvous.These surrogate models show significant advantages for mission design in three-body systems, in terms of both computational cost and capabilities, over traditional Monte Carlo methods.

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A graduate level curriculum covering topics in commercial spaceflight operations has been developed at the University of Colorado at Boulder. This paper outlines the high level insights gained through this process with the explicit objective of enabling dissemination to other institutions of higher education. Furthermore, several synergistic areas in the domains of technology, business, and operations have been identified that are benefiting from collaboration between industry and academia. Continued efforts in these areas are expected to produce innovation and improved technological solutions for the space industry.The focus of the curriculum is commercial activities; however, it would be naive to ignore the extensive experience and body of knowledge generated by government space activities. While some commercial activities seek to specifically streamline operations to avoid pitfalls of government spaceflight operations, the combined activities from governments across the globe in both military and civil space are crucial components of this curriculum. In many cases, this interaction with government entities is obvious, as is the case when government entities serve as the regulator of spaceflight operations or when they serve as direct customers to commercial providers. Going further, there is much experience in the realm of operations resident within government institutions, and this resource is considered intricately relevant to commercial spaceflight operations.While fusing experiences and information from commercial and government sources provides an extensive background for a curriculum, the efforts described in this paper are further enhanced by including relevant academic experience and research. Bringing together commercial, government, and academic perspectives and strengths allows for a well-rounded comprehension of spaceflight operations and provides a capable platform to research and understand relevant issues and constraints spanning all spaceflight operations.Broadly speaking, the objectives of the Commercial Spaceflight Operations curriculum development effort are to educate students and facilitate collaboration between academic, governmental, and commercial entities.