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I'm knocking my head against something and for some reason I can't get it to work out -- I'm running an N-body simulation which uses an internal gravitational constant of 1, meaning that the timestep used is a function of the units of mass, length, and velocity.

But I don't know the relation that allows me to solve for the timestep, e.g. if I am working in a system of unit mass M = 2.3e9 M_sol = 4.6e39 kg, and unit length L = 1 kpc, and unit velocity V = 100 km/s, what is my unit of time for G = 1?

Can anybody help me out real quick? This is a very *duh* moment for me...

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# Internal G=1 unit conversion/systems for simulation timestepping

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