The Long-term Evolution of Geosynchronous Transfer Orbits

Interactive MATLAB script that predicts the long-term evolution of geosynchronous transfer orbits.

This MATLAB script implements a special perturbation solution of orbital motion using a variable step size Runge-Kutta-Fehlberg (RKF78) integration method to numerically solve Cowell’s form of the system of differential equation subject to the central body gravity and other external forces. This is also called the orbital initial value problem (IVP).

The user can choose to model one or more of the following perturbations:

• non-spherical Earth gravity (up to order and degree 18)

• point mass solar gravity

• point mass lunar gravity

After the orbit propagation is complete, this script can plot the following classical orbital elements:

• semimajor axis

• eccentricity

• orbital inclination

• argument of perigee

• right ascension of the ascending node

• true anomaly

• geodetic perigee altitude

• geodetic apogee altitude