Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> > Darren New <dne### [at] sanrrcom> wrote:
> >> The moon is also receeding from the earth due to tidal forces.
> > 
> >   But isn't this recession decelerating? It will stop when the Earth is
> > tidally locked with the Moon.

> I think that's how it usually works. I'm not sure in this case, given that 
> the sun asserts a greater gravitational influence on the moon than the earth 
> does.

  I don't think that's how it works.

  The Sun asserts a certain gravitational influence on the Earth-Moon system.
That doesn't affect how the Earth and the Moon influence each other.

  If we measure the absolute strength of gravity caused by the Sun, it
might be stronger than the strength of gravity between the Earth and the
Moon, but Sun's gravity is the same for both the Earth and the Moon.
Basically Sun's gravity "sees" the Earth-Moon system as one object.

> > Thus the Moon is not going to get very much
> > farther than it already is.

> I think we have a ways to go before the earth is locked with the moon. :-)

  Just a blink, when we are dealing with astronomical times...

-- 
                                                          - Warp

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