11. Such occultations occur when the moon's ascending node is near the vernal equinox, as was the case in 2007. 12. This is done by specifying the longitude of the ascending node ( or, sometimes, the longitude of the node .) 13. The Moon crosses from south to north of the ecliptic at its ascending node , and vice versa at its descending node. 14. Odd numbers are used for solar eclipses occurring near the ascending node , whereas even numbers are given to descending node solar eclipses. 15. If the orbit is retrograde, this increases the longitude of the ascending node , i . e ., node precesses eastward. 16. It has an orbital period of minutes, with right ascension of the ascending node of degrees and an argument of perigee of degrees. 17. The highest ascending node of the lunar orbit is in the vernal equinox, the lunar declination can go as far as 28?each month. 18. The Earth's equatorial bulge causes the orbital right ascension of the ascending node ( RAAN ) to prograde ( inclination < 90?) orbit. 19. Second, the longitudes of ascending nodes of the two bodies the points where they cross the ecliptic are in near-resonance with the above libration. 20. An ascending node at 6 p . m . was chosen to allow COBE to follow the boundary between sunlight and darkness on Earth throughout the year.
