A cubesat centrifuge for long duration milligravity research

abstract: We advocate a low-cost strategy for long-duration research into the ‘milligravity’ environment of asteroids, comets and small moons, where surface gravity is a vector field typically less than 1/1000 the gravity of Earth. Unlike the microgravity environment of space, there is a directionality that gives rise, over time, to strangely familiar geologic textures and landforms. In addition to advancing planetary science, and furthering technologies for hazardous asteroid mitigation and in situ resource utilization, simplified access to long-duration milligravity offers significant potential for advancing human spaceflight, biomedicine and manufacturing. We show that a commodity 3U (10 × 10 × 34 cm[superscript 3]) cubesat containing a laboratory of loose materials can be spun to 1 r.p.m. = 2π/60 s[superscript −1] on its long axis, creating a centrifugal force equivalent to the surface gravity of a kilometer-sized asteroid. We describe the first flight demonstration, where small meteorite fragments will pile up to create a patch of real regolith under realistic asteroid conditions, paving the way for subsequent missions where landing and mobility technology can be flight-proven in the operational environment, in low-Earth orbit. The 3U design can be adapted for use onboard the International Space Station to allow for variable gravity experiments under ambient temperature and pressure for a broader range of experiments.The final version of this article, as published in Npj Microgravity, can be viewed online at: https://www.nature.com/articles/s41526-017-0021-

Small satellite earth-to-moon direct transfer trajectories using the CR3BP

The CubeSat/small satellite field is one of the fastest growing means of space exploration, with applications continuing to expand for component development, communication, and scientific research. This thesis study focuses on establishing suitable small satellite Earth-to-Moon direct-transfer trajectories, providing a baseline understanding of their propulsive demands, determining currently available off-the-shelf propulsive technology capable of meeting these demands, as well as demonstrating the effectiveness of the Circular Restricted Three Body Problem (CR3BP) for preliminary mission design. Using the CR3BP and derived requirements from NASA\u27s Cube Quest Challenge, five different trajectory scenarios were analyzed for their propulsive requirements. Results indicate that the CR3BP is an effective means for preliminary mission design; however, limitations were noted in its ability to account for the lunar orbit eccentricity with respect to the Earth. Additionally, two available options of off-the-shelf propulsion systems are identified that can achieve the ΔV necessary for lunar capture, but have not yet been demonstrated in-flight --Abstract, page iii