The North Lunar Node (Ascending Node) is the point where the Moon’s orbit intersects the ecliptic—the apparent annual path of the Sun across the sky as seen from Earth—and where the Moon moves from the southern celestial hemisphere to the northern one, effectively “emerging” above the ecliptic. The lunar nodes are mathematical points rather than physical celestial bodies: they have no mass, emit no light, reflect no light, and therefore cannot be directly observed in the sky.
The North Node is directly involved in the formation of eclipses. Only when the Moon is near one of the nodes does it align with the Sun and the Earth within the ecliptic plane. During a full moon near the North Node, a lunar eclipse may occur as the Moon enters the Earth’s shadow. During a new moon near the North Node, a solar eclipse may occur as the Moon passes between the Sun and the Earth and casts its shadow upon the Earth’s surface.
If the Moon passes above or below the plane of the ecliptic, the geometric conditions required for an eclipse are not satisfied, and no eclipse occurs.
