> At 03:11 PM 3/28/01 -0800, James R. Cunningham wrote:
> >The speed varies.  In high orbit, you go slower.
>
>
> I think this is the core of the confusion..


No - just a part of the greater confusion :-)
The motion of an obsrever on the earth's surface does need to be taken
account of BUT the increase in velocity as the orbital radius decreases is
real and absolute.

Geosynchronous orbit is the radius at which the APPARENT motion of a
satellite relative to a surface observer is zero.
Below geosynchronous orbit a West to East travelling satellite in an orbit
at the equator will APPEAR to travel Eastwards. Above geosynchronous orbit
(and there are few of these) it will APPEAR to travel Westwards. This is
entirely due to matching the velocity of the planets surface. If the earth
had a different period of revolution (length of day) the satellite moions
would be essentially unaffected BUT geosynchronous orbit would be at a
different altitude than it is now ! :-)

Does that add to the confusion? :-)



RM

>
> On the surface of the earth, you're traveling eastward at about 515 MI/Hr
> at the equator. At 22500 (Geosync) you are traveling in the same direction
> at something like 2944 MPH. (or 3463 if that 22500 is above the earth's
> surface.
>
> In both cases, your relative velocity to a point on the earth's surface,
is
> zero.
>
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