Libration-point missions have been very useful and successful.Due to the unstable natures of most of these orbits,the long-time stationkeeping demands frequent maneuvers and precise orbit determinations.Earth-based tracking will have to undertake much more responsibilities with the increasing number of libration missions.An autonomous navigation system could offer a better way to decrease the need for Earth-based tracking.Nevertheless,when an autonomous navigation system is applied,there are three important factors affecting autonomous navigation accuracy,i.e.,the accuracy of initial conditions,the accuracy of measurements,and the accuracy of onboard dynamics for propagation.This paper focuses on analyzing the influence from the third factor and fnding an appropriate navigation dynamics,which can satisfy the requirement of estimation accuracy but not cause too much burden for onboard computation.When considering the restricted three-body model and the bicircular restricted four-body model as navigation dynamics,the astringency is not shown during the simulations.Meanwhile,when considering the influences of the Sun’s direct and indirect perturbations and the eccentricity of the Moon’s orbit,a new navigation dynamic model with the standard ephemerides is proposed.The simulation shows the feasibility of the proposed model. Libration-point missions have been very useful and successful. Due to the unstable natures of most of these orbits, the long-time stationkeeping demands frequent maneuvers and precise orbit determinations. Earth-based tracking will have to carry much more responsibilities with the increasing number of libration missions. An autonomous navigation system could offer a better way to reduce the need for Earth-based tracking. However, when an autonomous navigation system is applied, there are three important factors that allow autonomous navigation accuracy, ie, the accuracy of initial conditions , the accuracy of measurements, and the accuracy of onboard dynamics for propagation. This paper focuses on analyzing the influence from the third factor and fnding an appropriate navigation dynamics, which can satisfy the requirement of estimation accuracy but not cause too much burden for onboard computation .When considering the restricted three-body model and the bicircular restricted four-body mo del as navigation dynamics, the astringency is not shown during the simulations. Meanwhile, when considering the influences of the Sun’s direct and indirect perturbations and the eccentricity of the Moon’s orbit, a new navigation dynamic model with the standard ephemerides is presented. The simulation shows the feasibility of the proposed model