I was messing around with the Shoemaker levy nine, and I shot a venus to put it into a better orbit (not collision course) Then I waited for after perihelion, and modified the orbit. Then I turned it flat, orbited above Jupiter at 5000 km, and shot it on course for Io... WAY TOO FAST
It happened, that coming back in, Ganymede passed 75000 km from my Jupiter orbiter.
Then I changed to RK4 and back to Euler, so I don't know if after the 2nd pass of Jupiter you can see Ganymede again, and on the way in if it passes by Europa at a distance of 210000 km
Anyways, here is the file