Re: Kepler problem

["A. R. Marlow" <marlow@beta.loyno.edu>]

On Wed, 1 May 1996, Rauber, Joel Phys wrote:
> This cleared up several of my questions, but still isn't well posed enough. 
> Tell the astronomically correct formula? Would deriving
>
> period^2 = (4 pi (earth-sun distance)^3)/G(M+m)
>
> do??

If period refers to the rotation of stars, OK.

> I won't make any assumptions about the center of mass, May I assume a 
> circular orbit in the inertial frame; i.e. a statics problem in the 
> non-inertial frame?

I am not going to make any statement about what you can assume in an
inertial frame.  You may assume a constant distance between Earth and 
Sun, yes, but the condition of the problem is "by applying Newton's
laws in a frame in which Earth and Sun are at REST,..."

The claim is that Newton's laws work in noninertial frames --  if they can
be stated correctly without reference to an inertial frame, they ought to
be able to be applied without such reference.

A. R. Marlow                          E-MAIL:  marlow@beta.loyno.edu
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