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Re: ZetaTalk and Spaceguard UK (D8)

Magnus Nyborg wrote:
>>   Where
>>        M1 = Earth = 5.9763e+24 kg
>>        M2 = Moon = 7.3508e+22 kg
>>         r = 200,000 miles = 3.844E8
>>         G = Gravity Constant of Earth = 6.67E-11
>> And where the force of gravity between two objects is another
>> Newton law:
>>         F = G*M1*M2/r^2
>  and the centrifugal force is...
>          F = M2*v^2
> solve for equality F1 = F2 (if there is a solution, there must be a
> balance between the two formulas or the Moon would flie out of
> orbit) and you get...
>     G*M1*M2/r^2 = M2*v^2 or...
>     G*M1/r = v^2, which solved for v gives
>     v = sqrt(GM1 / r), which has been stated before

How can centrifugal force consider ONLY the mass of the orbiting body?
Doesn't the Moon have a greater gravity pull to deal with, per the
Inverse Square law?  We just don't put these together!  Can't!  They
don't work together as Newton is WRONG!

The Inverse Square law reduces the mass according to the distance.  We
did that, in the 1998 exercise, to compute the EQUIVALENT mass of the
Moon if on the surface of the Earth, if orbiting that close.  We kept
the velocity the same, as the mass had already been reduced.  If you saw
an elephant floating slowly by at inches per hour, 10 feet off the
ground, and someone said it was staying aloft due to the centrifugal
force generated by its great speed, you'd KNOW something was wrong,
intuitively.  Yet this is what this exercise demonstrated!  No one wants
to look at that elephant, and DEAL with the inability of Newton's
formulas to deal with it either!  You CANNOT put his Inverse Square law
together with his Centrifugal Force or Velocity laws.