PUBLIC MARKS with tags free & espace

ORSA is an interactive tool for scientific grade Celestial Mechanics computations. Asteroids, comets, artificial satellites, Solar and extra-Solar planetary systems can be accurately reproduced, simulated, and analyzed.

The Celestia Motherlode is a repository for various addons like textures, models or celestial objects for Celestia. Celestia is a free, interactive (real-time), 3D astronomy program. It doesn't just show you the sky as it can be seen from earth as most planetarium software does, but allows you to move to and view the universe from any point between the planets and the stars. The Celestia Motherlode hosts over 10 GB of Celestia addons by various creators, which extend or change the way Celestia renders the universe.

The Celestia Motherlode is a repository for various addons like textures, models or celestial objects for Celestia. Celestia is a free, interactive (real-time), 3D astronomy program. It doesn't just show you the sky as it can be seen from earth as most planetarium software does, but allows you to move to and view the universe from any point between the planets and the stars. The Celestia Motherlode hosts over 10 GB of Celestia addons by various creators, which extend or change the way Celestia renders the universe.