Show a movie of satellite images.
At http://www.jpl.nasa.gov/galileo/dialimages.html you can download a series of 120 computer generated images showing the Galileo satellite swinging into orbit around Jupiter. (If they are gone, I have copies)
ByJupiter allows you to show these sprites as a movie. Full instructions in the ReadMe file.
Now totally rewritten to be RISC OS 4 compatible.
The data files are in a separate download on the homepage.