Comprehensive NASA Cis-Lunar Earth Moon Libration Orbit Reference and Web Application

This work will provide research and trajectory design analysis to develop a NASA Cis-Lunar / Earth-Moon Libration Orbit Reference and Web Application. A compendium of feasible Earth-Moon libration transfers and orbits, it will bring multi-body orbits to a larger venue and offer design options from a different perspective, no longer thinking only in terms of point designs, but interactive exploration with insight into the larger space. It will provide the analyst with efficient access to user-defined and standard design parameters to allow efficient and fully informed decisions regarding robotic and habitat missions in cis-lunar space. To finalize a comprehensive NASA Cis-Lunar / Earth-Moon Libration Orbit Reference and Web Application begun using FY13 IRAD funding approved in May 2013. This GSFC reference will be available as a searchable web-based application to explore design options and generate essential trajectory data permitting both astrodynamics experts and non-experts (proposal teams and systems designers) to determine useable trajectories in the Earth-Moon (EM) system. It can be used by HQ management, JSC's DSH habitat concept teams, HEOMD, and other analysis teams to develop designs without performing numerous time-consuming point designs or trades. Completing such a reference would maintain GSFC's leadership role in EM libration orbit design and operations while providing other study teams with instant designs and quotes on mission design parameters such as delta-V (DV), propellant budgets, mission durations, launch requirements, and libration-orbit parameters. The related objectives of this study fall into four specific categories: detailed analysis of transfers; orbital maintenance and evolution; and application to a variety of other mission types, e.g. distant retrograde orbits useful for human exploration. Provide Detailed Analysis of EM libration transfers: This effort includes direct transfers, transfers using lunar gravity assist, and transfers via multi-body dynamics (manifolds) to reach EM L1,2 orbits. This analysis would cover the entire design space and complete trades for any and all transfers to/from EM L1 and EM L2 and transfers between them. The current design process can be painstakingly slow, especially for point design using numerical simulations. We will apply the successful IRAD Adaptive Trajectory Design (ATD) tool to assist in generating most of these designs. Working with Purdue University would allow us to generate complete families of transfers. Provide Stationkeeping and Evolution Analysis of all EM libration orbit types: This includes any orbit type (quasi-halo, halo, Lissajous, Lyapunov orbits, rectilinear, etc.). With the recent operational support of ARTEMIS, which maintained two spacecraft in both EM L1and EM L2 orbits, we implemented an optimal stationkeeping strategy that minimized DV requirements. But ARTEMIS represents only a subset of all possible orbits and constraints. We need to examine not only the stationkeeping of various EM orbit types, but also the perturbation effects of un-modeled or mis-modeled s/c properties such as momentum management and response to environmental conditions on our stationkeeping methods and navigation performance. The result of such a study would be to document ΔV budgets required for all EM libration orbit types, providing any team with ready access to critical mission planning data. Explore Lunar resonant orbits and Distant Retrograde Orbits (DROs). These orbit designs are becoming more popular with missions such as TESS using a resonant orbit and the Asteroid Return Mission using a DRO. These orbits can also have stable/unstable manifolds which we can apply to our design. Develop an Interactive Web Catalog. A development of a broadly useful NASA Cis-Lunar / Earth-Moon Libration online catalog necessary for use across NASA. Such an orbit reference does not currently exist. It will be populated by the analysis and algorithms from the objectives above. More »