Celestia is a spectacular OpenGL-based 3D Planetarium/Space
visualizer.
Download #1 features the latest version (as of early August 2019),
1.6.1, said to be compatible with 10.3.9 Panther and later. Tested and
confirmed to work at least with Tiger.
Download #2 features the source code of version 1.6.1.
Download #3 features version 1.6.
Download #4 features version 1.4.1. Supposed to work with both 10.3
Panther and 10.2 Jaguar. First Universal Binary version officially.
Download #5 features version 1.2.2 (PowerPC only).
Download #6 features version 1.1.4.
Regarding version 1.4.1:
While this version is early, and occasionally crashes, it is still a
real show-piece for your old Mac and makes an excellent educational
resource for students and science buffs.
Does not merely display the planets and their moons, but can also show
tours of the solar-system and the paths of various spacecrafts like
the Voyager missions.
There's a folder contained inside called CelestiaResources (inside a
directory on the image named Add to ~/Application Support ) that must
be added to provide texturing to planets, as well as 3d models for
satellites and motion tours.
For faster systems, you can fetch and add new 3D Models, Tours and Hi-
Rez textures as they are newly acquired from NASA at
<
https://celestia.space/>
There's a pretty remarkable community of users, constantly adding
content.
Compatibility
Architecture: PPC x86 (Intel:Mac)
v1.2.2 - Mac OS X up to 10.6.8 Snow Leopard
v1.4.1 - Mac OS X 10.2 Jaguar+
v1.6 & v1.6.1 - Mac OS X 10.3.9 Panther+ (according to documentation).
Confirmed to work with at least Tiger. Universal binary.