They are the reason for eclipse season, being the intersection necessary for the alignment of Sun, Earth and Moon.

Motion

The line of nodes, which is also the intersection between the two respective planes, rotates (precesses) with a period of 18.6 years or 19.35° per year. When viewed from the celestial north, the nodes move clockwise around Earth, I.e. with a retrograde motion (opposite to Earth's own

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