From: George Pinckney <gpinckney AT earthlink DOT net>
Newsgroups: nctu.club.astronomy,relcom.fido.su.astronomy,sl AT psycode DOT com,comp.os.msdos.djgpp,gac.physics.astronomy
Subject: Re: Orbits, planets, PLEASE HELP!
Date: Sat, 21 Mar 1998 11:04:25 -0500
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Jack Ostroff wrote:

>
>
> However, don't give up hope.  Accurate equations for these things have
> not been discovered for more than two bodies.  (Look for references on
> the "three body problem" for more history, which should also provide
> leads on computational methods.)
>
> Good luck.
>
> Jack (jack_h_ostroff AT groton DOT pfizer DOT com)
>  (the legal message below, if present, is automatically added by my
>   corporate firewall.  There is nothing confidential in this message,
>   which can be redistributed freely.)

  This brings to mind questions I've had for a long time.
At what level in physics is orbital dynamics taught?  Is it a case that the math for the two body problem
is pretty straightforward, and is easily referenced when needed?

Regarding the three body problem, I think us amateurs don't appreciate the complexities here.  We see
tables for planetary positions and think they are "cast in stone."  How far out in time do these tables
remain relatively accurate??  When calculations are made, are estimates made as to how accurate they are,
as in "accurate to within x seconds / year.

In what reading I've done it seems the underlying assumption is that the three body problem will never be
solved - that we will never discover math that accurately describes a >2 system.  Any thoughts?