Earth Gravity Field Model
Author: Tianjiang Shuo
Website: https://cislunarspace.cn
Definition
A mathematical model representing the Earth's non-uniform gravitational potential through spherical harmonic expansion. The paper uses JGM-series models in the precise force model to compute orbital perturbations in the Earth-centered and mid-course segments. Low-degree terms (J2, J4) describe orbital plane precession and perigee rotation caused by Earth's oblateness, while higher-degree terms capture irregularities in Earth's mass distribution. Compared to a simple force model considering only central gravity, the precise gravity field model yields higher orbital computation accuracy.
Application Value
This term在cislunar space missions中has important application value. In orbit design, it can be used foroptimizing transfer trajectories, reducing mission fuel consumption. In attitude control and dynamics analysis, it helps understandthe motion characteristics of spacecraft in complex gravitational fields, providing theoretical support for mission planning. In navigation and orbit determination, methods based on this termcan improve orbit prediction accuracy, supporting the development of autonomous navigation algorithms.
Related Concepts
- Conic Orbit
- Meshless Method
- Heliosphere
- Kepler's Equation
References
- 刘磊 等 - 2008 - 多约束条件下的地月转移轨道设计