On Tue, Oct 11, 2011 at 6:32 PM, David Scheidt <[email protected]> wrote:

> On Tue, Oct 11, 2011 at 4:06 PM, Anthony Jackson <[email protected]> wrote:
> > On 10/11/2011 5:34 AM, Captain Joy wrote:
> >
> >> No, but the angle a planet moves through given its current location
> >> on the ellipse, semi major axis, delta-T, and eccentricity is an
> >> equation that can be looked up.
> >
> > Actually, it isn't. There's no simple method of computing that, at least
> > accurately when delta-T is a significant fraction of the orbital period.
>
> Sure there are.  There's no closed form, but there are iterative
> methods that will produce a result with arbitrary accuracy.  There are
> libraries to do that in just about any reasonable programing language
> (and some unreasonable ones, like Common Lisp and javascript.)  you
> would care to write a program in.  Modern computation makes many hard
> problems easy with a little bit of brute force.  (Though Maple did a
> fine job solving Kepler's equation via Newton's method when I was in
> college, so it's not a problem that really requires a whole lot of
> computational brute force.)
>

I guess it depends on what you mean by "simple".  So: what's the simplest
iterative approach that you know of?


>
>
>
> --
> David Scheidt
> [email protected]
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-- 
Jonathan "Dataweaver" Lang
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