Planether is an open source 3d game that combines both fun and realistic physics, distances and proportions. Textures, sounds and code are all under free licenses.
GitHub: https://github.com/Jeija/planether
See GitHub for instructions on how to build it in Ubuntu / Archlinux. You can download MS Windows binaries here: https://github.com/Jeija/planether/releases/tag/Windows (mind that MS Windows is not as well supported as Linux).
The game uses OpenGL, OpenAL and GLUT with a lot of GLSL shaders. It features procedural generation of planetary surfaces within vertex and fragment shaders.
Planether includes all planets of our solar system as well as the earth's moon and proxima centauri. You can use a spaceship to navigate or move freely between the planets. One can either play in real time or use the timelapse feature.
Video / Pictures: 100% Actual ingame footage
Music: Tom Day - Who We Want To Be
This video, apart from the audio, is under a CC-BY-SA-NC license. For the audio, please respect the rights of the artist.
If you have any issue with the usage of the song in this video, please contact me (via YouTube or norrepli+yt [ at ] gmail.com and I will delete it immediately.