Orbit Xplorer - Version 2.0 Educational orbit and gravitation simulator for high school, college and beginning university physics and astronomy. Easily create, run, print and save a simulation. Includes 29 introductory to advanced premade simulations with activities page in html-format. Uses actual pictures of planets. Plot orbits in a plane or in 3D. View time, distances, speeds, accelerations and energies as they change. Zoom and change parameters during the simulation.