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The objective of this work is the development of efficient techniques to optimize the cost associated with transfer trajectories to libration point orbits in the Sun-Earth-Moon four body problem, that may include lunar gravity assists.
Throughout the years, different strategies have been proposed for the station-keeping around the libration point orbits. In this paper, a geometrical comparative analysis is performed between different approaches making use of the Floquet modes reference frame. Two particular station-keeping procedures are considered: the commonly used velocity constraint at the plane crossing, and the Floquet mode approach. The first method finds the Δv that ensures that the x component of the velocity vector is zero at a plane crossing, whereas the Floquet mode approach finds the Δv that cancels the unstable mode in the Floquet reference frame. It will be seen that both approaches have some basic common geometrical features, even when they are compared using high-order techniques.
Station-keeping maneuvers are required to maintain a spacecraft close to a Libration point orbit, where the size of these maneuvers depends on different perturbations and any unmodeled forces. In many missions, despite being small, frequent momentum unloads can have a large impact on the size of station-keeping maneuvers. In this paper we will show that applying momentum unloads in the Linear Approximation of the Non-Escape (LANE) direction can significantly reduce their impact on the station-keeping delta-v budget.
Particle motion near triangular libration point in Earth-Moon system
Long-period librations of Trojan planetary orbits in rotating three-body coordinate system
Nonperiodic motions near long-period librations about equilateral points of restricted three-body problem
Librational motion analysis for elliptical restricted three-body problem
Three dimensional resonance effects on particle motion stability near earth-moon equilateral libration points
Hovering lunar libration communication satellite stationary with respect to earth-moon system
Lunar libration center clouds indicated by luminosity observations
Second order theory for trajectories near lunar libration point based on four body model including sun, earth, moon, and satellite
Satellite stationkeeping in vicinity of unstable collinear libration points
Three dimensional, nonlinear resonance effects on motion of particles near earth-moon equilateral libration points
Long term effects of longitude gravity harmonics on semimajor axis of circular orbits, discussing resonant librating orbits use in satellite geodesy
Spacecraft libration point motion in restricted four body model including earth-moon orbit plane inclination to ecliptic, noting solar effects
Lunar libration clouds visual observations and observing ephemeris, discussing sightings from aircraft and photographic attempts
Approximative analysis on librational dynamics of deformable satellite
Thermal and tidal effect on Mercury libration