Kepler’s trigon – the orientation of consecutive Jupiter-Saturn synodic periods, showing the repeating triangular shape (trigon).
This of course follows on from the very recent Part 1 of the model. Since Jupiter and Saturn are the dominant planets in our solar system, we can speculate that they may have a significant effect on the obliquity of smaller bodies. Or they may not – no-one knows, but we can look at possible evidence.
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Precession of the Jupiter-Saturn conjunction (J-S) was worked out by Kepler centuries ago, as shown in his diagram to the right.

‘As successive great conjunctions occur nearly 120° apart, their appearances form a triangular pattern. In a series every fourth conjunction returns after some 60 years in the vicinity of the first. These returns are observed to be shifted by some 7–8°’ – Wikipedia.

Earth’s Axial Tilt, or Obliquity [Credit: Wikipedia]
First let’s get the approximate target numbers for the model.

‘The inclination of Earth’s orbit varies with respect to the solar system’s invariant plane with a period of roughly 71000 years.
. . .
Taken in conjunction with the 26000-year spin-axis precession, the 71000-year orbit precession causes a 41000-year oscillation in the tilt of the earth’s axis, about plus or minus 1.3 degrees from its average value of 23.3 degrees. This number is not absolutely stable – it depends on the combined positions of all the planets through time.’

Astronomy: precession of Earth (Washington State University)
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Origin of the 100 kyr Glacial Cycle: eccentricity or orbital inclination?

‘Spectral analysis of climate data shows a strong narrow peak with period ~ 100 kyr, attributed by the Milankovitch theory to changes in the eccentricity of the earth’s orbit. The narrowness…