Have a go at Super Planet Crash

There are very frequent announcements of the discovery of exoplanets. These are planets that go round stars other than the Sun. You can't see them with telescopes. They are so far away and the light reflected from them is so dull. Instead they are detected by picking up the small dimming effect when they pass across the face of their star, or by the way they make the star slightly wobble as they orbit. Both of these effects are greater if the planet is the size of Jupiter. Since we can't study systems like this directly by observation, computer modelling helps. Here's one such programme, made into a game: http://apod.nasa.gov/apod/ap150112.html Click the link and have a go at Super Planet Crash. My first few goes ended in catastrophe. I then played safe by installing 11 Earth sized planets and my system lasted 500 years. I got 115,766 points.

Then I tried again with a couple of ice giants and a giant planet thrown in as well. It was stable for 500 years and I managed 295, 400 points. Can you beat that? The game goes slowly so you might want to press fast forward when you are sure that it seems stable.