More background on 74 74.4 year cycle ....

  1. 2,410 Posts.
    More background on 74 74.4 year cycle .
    https://chiefio.wordpress.com/2013/01/29/arctic-standstill-tropical-saros/
    1)
    This article also suggests introduces the 18.03 Saros cycle which is kind of new to me.
    [Author]
    So every 18.6 years we get a more extreme north / south range of lunar tidal forces. This gives a somewhat better description of it:
    https://en.wikipedia.org/wiki/Lunar_standstill
    but the basic point is just that if you are looking for water being pulled toward / away from the poles, that will be happening on an 18.6 year cycle, while if you are looking for water to be pulled toward / away from the equatorial areas (eclipse times) that will be on an 18.03 year Saros cycle. Those two will interact. I get a 335.35 year product of the two.
    The Moon’s maximum and minimum declination also varies because the plane of the Moon’s orbit around the Earth is inclined by about 5.14° to the ecliptic (the plane of the Earth’s orbit around the Sun), and the direction of lunar orbit inclination gradually changes over an 18.6-year cycle, alternately adding to or subtracting from the 23.5° tilt of the Earth’s axis. As a consequence, the maximum declination of the Moon varies from roughly (23.5° − 5° = 18.5° to (23.5° + 5° = 28.5°. As a result, at minor lunar standstill, the Moon will change its declination during the nodal period from +18.5° to −18.5°, which is a total movement of 37°. Then, 9.3 years later, during the major lunar standstill, the Moon will change its declination during the nodal period from +28.5° to −28.5°, which is a total movement of 57°, which is enough to take its culmination from high in the sky to low on the horizon in just two weeks (half an orbit).


    2) [LuckyMojo]
    The bit I  have introduced into my own analysis and cannot find mentioned?? is average Solar Cycle Length .. Was this the smoking gun they missed?
    https://en.wikipedia.org/wiki/Solar_cycle
    Fossil records suggest that the Solar cycle has been stable for at least the last 700 million years. For example, the cycle length during the early Permian is estimated to be 10.62 years[9] and similarly in the Neoproterozoic.[10][11]


    74.4 / 4 = 18.6
    74.4 / 7 = 10.62
    Last edited by LuckyMojo: 17/09/18
 
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