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frbee
2009-Jul-17, 10:48 PM
When the moon crosses the ecliptic at its ascending node? Does this happen at a different place any time? Does it go farther away from the ecliptic each time?

grant hutchison
2009-Jul-17, 11:17 PM
The moon's orbit precesses in the ecliptic plane, so the nodes move continuously, regressing once around the sky every 18.6 years.
So, yes, when the moon passes through its ascending node on the ecliptic, it's in a different place on each successive month.
It doesn't go farther from the ecliptic each time, since the inclination of its orbit is reasonably constant.

Grant Hutchison