To calculate the Moon's orbit (or any Solar system body's) accurately,
you have to perform the many-body calculation of most of the Solar system.
That is straight forward, but costs a bit in computing time. That's how
it is done.
  The three-body problem cannot be solved analytically, but it is, again,
straight forward to do numerically. You program all the forces, e.g.,
gravity, tidal forces and tidal friction, in the Solar system case, and
supply the starting positions and velocities, and then you advance time
and see how it evolves. The accuracy would be determined from running the
simulation backwards in time and compare with observations. All the cycles
of the Moon's orbit will be accounted for by this procedure, if all the
relevant physics is included in the model.
  A physical model is not restricted to an analytical formulation of the
problem - that is most often not possible. 
  I do not know the innards of Starry Night, but my bet would be that it is
based on a parametrized version of the above. So indeed a table, but based
on many-body simulations covering both the past and the future. That is my
bet - not a statement of absolute truth.
  

    Regards,

      Regner

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Quoting Steven Jones <steven@xxxxxxxxxxxxxxxxxxxx>:

  

  


Regner Trampedach wrote:

  Steven Jones,

  If we don't have a mathematical model of the Lunar orbit around the Earth,
how on Earth (sorry for the pun) would we be able to make such lookup
tables?
Or were they handed down to us by divine powers?
  

Simple, the look-up tables are simply based upon the last 200
years of accurate observations relative to the Earth. By means of
referencing them we can accurately go a couple of thousand years into
the past or future with an error-margin of course. This does not
constitute having a mathematical model, no-one on Earth has yet brought
one forward. What about the three body problem also?



You forget Regner that just because I don't happen to go to a
university or have a qualification, you are actually speaking to one of
the best geocentrism experts in the world, and someone who is also
familiar with computer programming having co-developed GU 3. Redshift,
Starry Night, they are all the same, the moons motion is predicted by
means of a table, it is not calculated on anything other than a table!



You should know that the moon's orbital period is known as a Sidereal
Month, 27.321661 days. Sounds simple doesn't it, but it isn't! This is
an average, because even in your model many factors come into play.
Your very own heliocentric model will give you a hell of a time if you
try and work it out, it's not just the moon cycling from new moon to
new moon, because the Earth itself has moved and by your own admission
the Earth's orbit is also slightly elliptical. Do you really know what
your talking about on this? Do
you know the difference between Sidereal, Anomalistic, Synodic, Draconic,
Saros and the Tropical
lunar month? All of these play a part in helping to understand the
motions of the moon, but as yet, no-one has put them altogether to
create a model of the orbit! It's just so unpredictably variable. The
dynamic range of a synodic month is is between 29.27
to about 29.83 days, and for now this is pretty much as good as it all
gets, but this is not good enough for a mathmatical model that can
predict without err when the moon will rise. Newton himself spend a
great-deal of time on this, but claimed it gave him a headache.



Steven.



    You usually want the Lunar orbit around the Earth, with respect to the
Earth.
Of course you could just as well calculate the Lunar orbit around the Earth,
with respect to one of Saturn's moons. But that is not particularely
interesting
for us as humans.
  You can choose any reference frame you want. That is your privilege as the
one doing the calculation. If you choose an inertial frame, then it's easy;
all the laws of physics are unchanged. If you, e.g., choose a rotating
reference
frame - like the Earth, according to HC - then it gets more complicated, but
still very doable. You just have to include all the fictive forces arising
from that coordinate transformation, such as centrifugal and Coriolis
forces.
  There is NOTHING dubious about choosing the Earth as a reference frame for
a
calculation and still adhere to HC.
  Somebody on this board (I don't remember who) once leaked the hush-hush
secret that NASA were doing their calculations referenced to a stationary
Earth. NASA, as well as ESA and JAXA, etc., obviously choose the Earth to
be the reference frame and there is nothing secret or dubious about that.
Also
obvious, is that they include all the fictive forces from that coordinate
transformation.

     Regards,

        Regner Trampedach

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Quoting Steven Jones <steven@xxxxxxxxxxxxxxxxxxxx>:

  
  
    

  


philip madsen wrote:

  
  DIV {
	MARGIN: 0px
}
  
  
  
  

Phillip, currently, no-one on Earth can give you an accurate model
predicting the orbit of the moon without the use of "look-up" tables
which are all geocentric based. No need to attack Allan in this way.
He's a bright cookie!



Steven.



  
  Dear Paul,
  Why did you find it necessary to patronise Regner in that way?
Regarding the 'real thing' what in heavens name
is Regner doing that no-one else is?
  Â 
  Jack
  Â 
  Well from my view, Regner is a professional
Astronomer, I'm not even an amateur..But I got Wiki and a million web
sites to help me follow his words. . 
  Â 
  And Allen cannot even tell us how many
rotations the moon has. 
  Â 
  I dare not ask him the next question
concerning the axes of the moons rotations. 
  Â 
  Philip.