How is the zero hour defined and where does it map to in the sky ... The Ecliptic crosses the celestial equator at two points. One point marks the Vernal (or spring) Equinox and the other the ...

This celestial geometry marks the changing ... to spring in the Southern Hemisphere. The word "equinox" is Latin for "equal night," one of two days per year when the lengths of daylight and ...

Just what is an equinox, and why does it occur? The Earth moves in two different ways ... This tilt is always toward the same point in the sky, called the celestial pole, no matter where in ...