>From: "Matthew Mucker" <mmucker@AIRMAIL.NET>
>> Actually, I think this is backwards.  I'm no expert, but after
>> reading Gene Krantz' autobiography, I reacll that NASA had
>> lots of problems with stuff like this until they realized
>> that at a lower orbit, a body must revolve around the earch
>> much faster to keep it in orbit.  Any experts out there who
>> can clarify?

>Object of mass m rotating around a gravitation field of strength 'mu'
>so-called Earth:
>Centigugal force = m * V * V / R                (V is velocity and R the
>radius)
>Weight = mu * m / ( R * R )
 (snip)
>Jeszs Gonzalo

In english:  At a higher orbit you are traveling faster.  As in,
if you were standing still and watched it go by.  (So-called,
linear velocity).  But at the same time, it takes longer to
complete an orbit, so it "goes around" slower (so-called,
angular velocity).

This is a favorite story of mine, because the best and brightest
missed the point the first time.  Not that I knew anything, I
read about it in the paper back then, and I hope I remember
it right.

On one of the early Gemini flights they did a rendezvous experiment.
As I recall, a lot of the Gemini program was aimed towards working
out all the particulars about rendezvous-and-docking for the
subsequent Apollo (moon shot) program.  This flight predated
the later docking with other capsules, adapters, Russian
ships, etc.  What they did was to put lights on the booster
stage which remained in orbit (or near-orbit) along with the
flight capsule.  Early in the mission they practised the
rendezvous maneuver with this booster.  It didn't work.
Basically the complaint was "the more I tried to catch
up with it, the farther away it got".  So they went home
and did some head scratching, and presumably looked at
those formulas again, and said, "Oh...now we get it".

Essentially you slow down, drop to a lower orbit, which
lets you swing ahead of the thing you want to catch up with.

Orbital mechanics is interesting.

Barry

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