An Etymological Dictionary of Astronomy and Astrophysics

One of the two points of intersection of the orbit of the Moon with the plane of → ecliptic. Indeed, the lunar orbit is tilted by about 5 degrees relative to the ecliptic. The revolution period of a lunar node in ecliptic is 18.61 years. Due to perturbation by the Sun, the lunar nodes slowly regress westward by 19.3° per year.

See also → ascending node; → descending node.

Etymology (EN): → lunar; → node.

Etymology (PE): Gereh, → node; gowzahri, related to gowzahr, → draconic month.