Yes it IS hard to make stable systems of 3 or more ... maybe that is also true of planetary systems.
]]>It will ask you what mass you want (if you don't want it to ask, there is an "ask" toggle button)
]]>I find it a little mesmerising. I like to set things going and check back every so often to see what is happening.
The gravity simulation is fairly good ... I tested internally with the measurements of Sun/Mercury/Venus/Earth and they behaved nicely
Comments/suggestions?
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