On Tue, Oct 11, 2011 at 5:31 AM, Roger Burton West <[email protected]> wrote: > On Tue, Oct 11, 2011 at 05:29:32AM -0500, Captain Joy wrote: >>I'm not sure I understand; in fact I'm sure I don't. If you know where on >>the ellipse your planet is at at t=0, and you know the semi-major axis and >>eccentricity of the orbit, it seems like figuring what angle the plant moves >>through each Delta t thereafter should be a fairly simple equation. > > It isn't. > > You can take Hal's approach and slice the orbit into smaller and smaller > delta-T segments, working out the swept area. Or you can use calculus. > But neither of these is going to be _simple_. >
Well, other people have done the hard work of builing approximations to the solution, so he nearly pick the one that's good enough for him, and use it. That's simple enough (I'd actually thought someone had a closed form solution, but it appears not.) -- David Scheidt [email protected] _______________________________________________ GurpsNet-L mailing list <[email protected]> http://mail.sjgames.com/mailman/listinfo/gurpsnet-l
