[Shift+left-click+drag] or [,.] (comma,full-stop): Change Field of view
[Ctrl-V] : Changes vertex shading options
[Shift-R]/R : Changes texture mapping
[`] (backtick) : Toggle FPS display. Note if this drops below 6 you may crash
the app
[Home/End] : Move closer/farther
[Cmd-f] : toggle full-screen/window modes
[Ctrl-R]: Split view vertically
[del] : delete active view
[/] : show constellation shapes
[Ctrl-B] : show constellation borders
[U] : Enable galaxies
[Shift+(] and [Shift+)] : Galaxy brightness controll
[Shift+^] : turn Nebulae on/off
[O] : show orbits
[Ctrl-S]: Adjust display of stars
Direction keys: Pitch and yaw
Shift + direction keys: rotate around object
Right click+drag: rotate and change perspective
Links:
Celestia