Numerical Prediction of Orbital Events

MATLAB script and user's manual for predicting important root-finding and extrema orbital events

This submission is an interactive MATLAB script named npoe.m that can be used to propagate spacecraft in Earth orbits and model important orbital events. This script implements a special perturbation solution of orbital motion using a variable step size Runge-Kutta-Fehlberg (RKF78) integration method to numerically integrate Cowell’s form of the system of differential equations. Orbital events are predicted by embedding the RFK78 algorithm within Brent’s derivative-free methods for finding the single roots and extrema of nonlinear equations. The user can control both the integration and root-finding convergence criteria.