The Model assumes all UFO's fly according to a simple automaton, The pilot flips a coin to decide when to take off. The destination is either earth or the closest other asteroid or planet. And the UFO flies at constant speed directly to the target until it is reached.
In the movie asteroids and planets within 5 AU of the sun are shown. The Earth is not market. But you can see which obj it is. Similarly, Mars.
Obj marked with a green "+" currently have >10 UFO's in residence. A "+" cross means 1-10 UFO's. Blank means none.
The movie starts with with UFO's randomly scattered around the system out to 100 AU. It quickly settles down to a routine. For a while it looks like convoys of UFO's are "targeting" Earth. But this is not the "long run" pattern -- likely just the transit at simulation start-up.
Play movie (.avi) here.
Original USENET post here
View code here.