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Re: ZetaTalk and Spaceguard UK (D8)


 Greg Neill wrote:
> The [6.67E-11 ] exponent is on the value for G, the
> gravitational CONSTANT.

We have a gravitational CONSTANT?  Gravity is a factor of both masses,
and increases in proportion to the size of the masses involved, per the
Inverse Square law!  Or can't we put both these equations on the same
page, as the Zetas stated.

M.C. Harrison writes.
> The force of gravity is an inverse square law, which means
> a mass will experience a force due to another mass according to
> the equation F=M1*M2/r^2 where M1 is one mass, M2 is the
> other mass, and r is the separation of the masses. ...

So if we put these two "laws" on the same page, then G in the equation
for a "low mass object" might be a constant for a satellite, but should
be COMPUTED for the Moon.  Computing this, then, gives us the following
equation (below) for the correct velosity of the Moon. Lets plug in the
PROPER force of gravity between the Earth and Moon in the velosity
equation (which after all should work if your math can be put on the
same page), and see what we get!  Or can't we put both your equations on
the same page, as the Zetas stated.

Magnus Nyborg
>   v = sqrt( G*M / r )
>
>  Ground orbit (if possible) -
>      v = sqrt( 6.67E-11 * 5.976E24 / 6.378E6 ) = 7905 m/s
>   Satellite orbit -
>      v = sqrt( 6.67E-11 * 5.976E24 / 6.478E6 ) = 7844 m/s
>   Moon orbit -
>      v = sqrt( 6.67E-11 * 5.976E24 / 3.844E8 ) = 1018 m/s
<============ WRONG FORMULA FOR HIGH MASS MOON

But the Moon's velosity should be:
   v = sqrt( G*M / r )
   v = sqrt( (Inverse Square) / 3.844E8) = ?
   v = sqrt( (F=M1*M2/r^2) / 3.844E8) = ?
   v = sqrt( (F=5.9763e+24 kg * 7.3508e+22 kg) / 3.844E8) = ?
<============ RIGHT FORMULA FOR HIGH MASS MOON

Where
      M1 = Earth = 5.9763e+24 kg
      M2 = Moon  = 7.3508e+22 kg
       r = 200,000 miles = 3.844E8
     G*M = Gravity Constant of Earth = 6.67E-11 * 5.976E24
                 (only valid for low-mass orbiters)

And I'll bet the resulting m/s are no where near the 1023 m/s or 1018
m/s of the Moon's actual rate.