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Hello Mike,
I'm getting a headache from all this lunar standstill stuff. I'd like to make an attempt to simplify an answer to what is a very interesting observation/question you raised.
If you look at the yearbook at the declination of the Moon, say comparing those of the First Quarter (waxing) to the Last Quarter (waning) the Moon is idea much further south when waxing compared to waning, in the second half of this year. In the first half, it is reversed - the waning period is further south.
As mentioned by others below (above?) the Moon's orbit is tilted by 5 degrees to the Earth's and because the ecliptic varies by + 23 to -23 degrees the Moon can go up to +28 to -28. The key to this whole discussion is that the Moon's orbit, including it's tilt is fixed in space (centred on the Earth ofcourse) - like the NCP continues to point to the same location near Polaris no matter where the Earth is in its orbit. In June the Full Moon happened to be south of the ecliptic with New Moon, North. In December the Earth is now on the opposite side of its orbit and the Full Moon is north with New - south. They have reversed. This same effect would then follow for the periods of waxing and waning. This is roughly the pattern it will follow for every year but because the Moon makes about 12 and a half orbits in a solar year the dates for the lunar phases (where the Moon is in its orbit for any particular date) will vary a lot from year to year.
This applies for any year. The lunar standstill, extremes of declination, will just make this effect a little more extreme or obvious.
Is this any easier to follow.
Regards
Glenn
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