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A comment on “The moon blew up without warning and for no apparent reason”. Parent comment

Re:“The moon blew up without warning and for no apparent rea... by dahart on Thursday September 21, 2017 @06:11PM (#15307798)
Super fun thought experiment and project! Did you simulate n-body gravity, or just the Earth's? I couldn't tell from the project page or comments.

My son just asked me yesterday what would happen if the moon went away, and he hasn't even read any Stephenson yet.

Good question - another side to this though experiment! What happens if tides cease to exist? Could that cause enough change in the oceans or weather to pose a threat to life on earth? What if animals can't hunt at night anymore? What else do we rely on the moon for?

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Re:“The moon blew up without warning and for no apparent rea... by hexane360 on Thursday September 21, 2017 @09:22PM (#15308728)
>Gravitational interactions between all bodies. I use an extraordinarily naive direct summation approach, which scales as O(N^2) and is horrible. A huge improvement would be to approximate forces from distant bodies with some kind of multipole expansion, and store masses in a balanced tree – this is known as a Barnes-Hut simulation.
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