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Re: ZetaTalk and Spaceguard UK (D8)


In Article <3B5EFB62.49A56D5F@zetatalk.com> Nancy Lieder wrote:
> 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( (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)

I forgot a divisor by the square of r.  That line should be:
   v = sqrt( ((5.9763e+24 kg * 7.3508e+22 kg)/ 3.844E8^2) / 3.844E8) = ?

 <============ RIGHT FORMULA FOR HIGH MASS MOON

Sorry.