Halo orbit to science orbit captures at planetary moons. (May 2017)

• Record Type: Journal Article
• Authors: Bokelmann, Kevin A.; Russell, Ryan P.
• Is Part Of: Acta astronautica. Volume 134(2017)
• Page Start: 141
• Page End: 151
• Publication Date: 2017-05
• Subjects: Three-body problem -- Hill approximation -- Manifolds -- Capture -- Halo -- Orbit -- Planetary moons; Astronautics -- Periodicals; Outer space -- Exploration -- Periodicals; Astronautics; Periodicals; 629.405
• DOI: 10.1016/j.actaastro.2017.01.035
• Languages: English
• ISSNs: 0094-5765

Abstract

Abstract: Ballisticly connecting halo orbits to science orbits in the circular-restricted three-body problem is investigated. Two classes of terminal science orbits are considered: low-altitude, tight orbits that are deep in the gravity well of the secondary body, and high-altitude, loose orbits that are strongly perturbed by the gravity of the primary body. General analytic expressions are developed to provide a minimum bound on impulse cost in both the circular restricted and the Hill's approximations. The equations are applied to a broad range of planetary moons, providing a mission design reference. Systematic grid search methods are developed to numerically find feasible transfers from halo orbits at Europa, confirming the analytical lower bound formulas. The two-impulse capture options in the case of Europa reveal a diverse set of potential solutions. Tight captures result in maneuver costs of 425–550 m/s while loose captures are found with costs as low as 30 m/s. The terminal orbits are verified to avoid escape or impact for at least 45 days. Highlights: Derives an analytical equation for the floor delta-V to connect orbits. The equation is derived in both the CRTB and Hills models. Calculates the floor capture cost for captures at multiple moons of interest. Finds transfers from L2 halos at Europa to low and high altitude science orbits. Comparison shows all actual transfers costs are above the predicted floor.