Orbiter (simulator)
Orbiter (official typeset as ORBITER) is a freeware space flight simulator program developed to simulate spaceflight using realistic Newtonian Physics. The developer, Martin Schweiger, felt that space flight simulators at the time were lacking in realistic physics based flight models and decided to write a simulator that made learning physics concepts enjoyable.
The simulator was first released on 27 November 2000, with the most recent of several versions 100830 released on 30th August 2010.
Orbiter has been used as a teaching aid in classrooms, and a community of addon developers have created a multitude of addons to allow users to fly assorted real and fictional spacecraft and add new planets or solar systems.
Read more about Orbiter (simulator): Included Spacecraft, Orbiter Add-ons