2024/05/09 by Yongzhang Yang, Yang, Yongzhang, Jianguo Yan +7 · 1 citation
Earth and Planetary Sciences · Engineering · #Earth and Planetary Astrophysics (astro-ph.EP) #FOS: Physical sciences #Geophysics and Gravity Measurements #Inertial Sensor and Navigation #Spacecraft Dynamics and Control
paper · pdf · doi:10.48550/arxiv.2405.05519
openalex publication_date 2024/05/09 · openalex created_date 2024/05/11 · openalex updated_date 2026/07/28
High-precision ephemerides are not only useful in supporting space missions, but also in investigating the physical nature of celestial bodies. This paper reports an update to the orbit and rotation model of the Martian moon Phobos. In contrast to earlier numerical models, this paper details a dynamical model that fully considers the rotation of Phobos. Here, Phobos' rotation is first described by Euler's rotational equations and integrated simultaneously with the orbital motion equations. We discuss this dynamical model, along with the differences with respect to the model now in use. We present the variational equation for Phobos' rotation employing the symbolic Maple computation software. The adjustment test simulations confirm the latitude libration of Phobos, suggesting gravity field coefficients obtained using a shape model and homogeneous density hypothesis should be re-examined in the future in the context of dynamics. Furthermore, the simulations with different k2 values indicate that it is difficult to determine k2 efficiently using the current data.