A patriot must always be ready to defend his country against his government.
Edward Abbey
Edward Abbey
Our Worlds
Celestia
Celestia... Space simulation that lets you explore our universe in three dimensions.
Celestia runs on Windows, Linux, and Mac OS X.
https://celestiaproject.space/
Downloads for each OS:
https://celestiaproject.space/download.html
Addons:
http://www.celestiamotherlode.net/
A (not so) Brief Introduction to Celestia Addons:
https://www.classe.cornell.edu/~seb/celestia/addon-intro.html