Yet another orbital gravity simulation software
  IMPORTANT NOTICE: this JAVA applet is developed using JDK 1.6.0_05. In order to have it running the Java Runtime Environment (JRE) version 1.6.0_05 or higher has to be installed on the client PC. You can download it from
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  The aim of this software is to simulate the solar system gravitational field with a number of objects (planets, moons and spacecrafts) and allows the user to drive vessels around the space using gravity guided manouvers.
I've done this just as an experimet which allowed me to learn Java while playing with a so exciting topic. If you're looking for a more professional orbital simulator I suggest you to have a look at Orbiter, which highly inspired this work. Orbiter implements a full 3D graphics environment with excellent visual effects merged with an accurate physics engine.
  Copyright (c) 2008 by Simone Pedruzzi - E-Mail