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The moon follows 5.14 deg inclined path. the ecliptic and the Moon's path coincide are called 'nodes', and they travel around the ecliptic in a period of 18.66 years.

Once every 18.66 years, the ascending node coincides with the vernal equinox, and the Moon will reach declinations of about +28° and -28° (much more than the Sun, which reaches ±23°); this is called a 'major lunar standstill'. 9.33 years later, the opposite is true, and the Moon will only reach ±18° during a 'minor lunar standstill'.

I read https://answers.yahoo.com/question/index?qid=20121018091531AArHgNS&guccounter=1 here, the precise declination of moon is at +28.88 deg, over the earth. Where can I find the exact, value from other sources? I don't know how he found this value? " I get plus or minus 28 degrees 53', over a 18.6 year cycle. Eventually it will cover the whole region, but it will take many thousands of years (depending on how close you consider it has to get to a point to cover it.) " 28 degrees and 53' = 28.88 deg

The 0.88 deg, to time is 53 min, I think it seems to coincide with the fact the moon rises, 53 min sooner, over each day. Is this related to this? 13.2 deg * 4 min/deg = 53 min

The maximum inclination of the moon, for standstill, can it be specified by the eclipse point? On, august 21 2017, an eclipse occurs in 28.88 deg on latitude point. Is this angle the same as the inclination angle specified here: http://www.umass.edu/sunwheel/pages/moonteaching.html - 28.8 deg.

I just want 28.88 deg = 28 deg 53' confirmed.

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I just want 28.88 deg = 28 deg 53' confirmed.

Yes, 0.88 degrees is equal to 53 arc minutes, so 28.88 deg = 28 deg 53'.

But the Yahoo source is off in its value. According to this reference, the maximum declination is closer to 28° 44' (28.73°).

Title: Extreme declinations of the moon. Authors: Können, G. P. & Meeus, J. Journal: Journal of the British Astronomical Association, Vol. 82, p. 192 - 193 Bibliographic Code: 1972JBAA...82..192K Available on NASA Astrophysics Data System.

That reference gives a declination of 28° 43' 21" on Sep 15 2006. Using the Lunar Polynomials from the Astronomical Almanac Online, which permit you to calculate the declination to a far greater precision than you can know the time, I calculate a value of 28° 43' 22". Thus, I trust the article.

28° 43' 22" = 28.723 degrees (Sep 15, 2006). The maximum between 1920 and 2050 is 28° 44' 11" = 28.736 degrees (March 15, 1932).

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  • $\begingroup$ Thanks for clearing this up. I also found from nasa, the maximal moon declination for the moon is at 5.3 deg, to the earth. If the earth angle to to the orbital plane to the sun is 23.5 deg, at the time of 5.3 deg, then 28.8 deg would come up. I assume that is why umass.edu/sunwheel/pages/moonteaching.html Assumes 28.8 deg is the maximal. And the one from yahoo is bit of. The measurements are over decades, with varying equinox angles, from the link you provided. $\endgroup$ Dec 7, 2018 at 10:08

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