B Adorable Gravity Demo - National Medals Lab

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ergospherical said:
Cute demo
... of an interactive gravitational body simulator.
 
Hm. I'm not sure just how good it is.

I just set two massive bodies co-orbiting, which worked fine until I added a third smaller body.
The third boy seemed to orbit only one of the massive bodies, and remained unaffected by the other.
1639522636506.png
 
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It would be nice to see how they coded it and what shortcuts they used (which might explain that behaviour you found for the restricted three body problem) but I couldn't find any documentation.
 
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