JSatTrak is a Satellite tracking program written in Java. It allows you to predict the position of any satellite in real time or in the past or future. It uses advanced SGP4/SDP4 algorithms developed by NASA/NORAD to propagate the satellite orbits.
A self-sufficient java framework for numerical solution of ODEs (diff eqs) and visualization. Samples are aeronautics/astronautics/physics/rocketry themed. Focus on clean design, modularity, reusability and documentation. Educational project.