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Re: Moon's synchronism (not very long)



At 04:45 PM 3/30/98 -0800, John wrote:

Jim,

What is your preferred explanation for the increase in the length of the
day?=A0 (BTW, I am not at a loss for alternate hypotheses however unlikely
they may be; I just wonder what yours is.)

John, now it comes to me what your question is: If there are no tidal=
bulges,
how is torque applied to the Moon -- and consequently to the Earth , which
slows it down. (Sorry for my previous ungracious reply.) I assume that we
are
talking about water tides here -- one can't be sure in this thread -- but=
here
_I_ am. and assume that you are too.

I take it that you have in mind research by oceanographers or geophysicists=
or
the like where a calculation is made to look at the Moon's changing angular
momentum and determining what the required torque would need to be and then
come to the conclusion that the so called tidal bulges must lag (or is it
lead)
the Moon's transit by -- the latest I think is 6 degrees, but it changes.

The problem here is that these oceanographers have ASSUMED the existence of
tidal bulges and then made their calculations. =20

This does _not_ establish that there _are_ tidal bulges -- only that if=
there
_were_ such things their lag might explain the required torque. But these
oceanographers don't seem to have ever asked themselves whether there really
_are_ such things. In deed I have asked a couple of these authors, and the
response is something like "Of course there are tidal bulges, there are=
tides
aren't there. They seem to have accepted this myth in JrHS from ill prepared
teachers and carried it from there -- in much the same way that the same
people
still believe that there is a substance called "heat" which flows. (sorry,
the
pixies made me say it.)

As for the real cause, I refer you to David Bowman's post of today (Tues)
-- of
which I am still trying to make sense -- but he does talk about this there.

Folks all,=20
I am truly sorry that this tidal bulge thing has come up again this year.
Last
year I started to work on a WWW page which has some information which ought=
to
answer many of these questions - at least it has _my_ imperfect=
understanding
and it would be a good idea to visit there before asking me questions here. =
I
_do_ have some still unanswered questions of my own. I will try to at least
list them there. One is the idea that a "tidal bulge" could not keep up=
with
the Moon's transit. I am trying to understand David Bowman's point in this
regard, but he is arguing against geophysicists generally -- but then we all
know how I tend to question them. (:-) =20

Jim Green
JMGreen@sisna.com

http://www.sisna.com/users/jmgreen