[:wiki] An equi­nox occurs twice a year, when the tilt of the Earth’s axis is inclined neither away from nor towards the Sun, the centre of the Sun being in the same plane as the Earth’s equator. The term equi­nox can also be used in a broader sense, mean­ing the date when such a pas­sage hap­pens. The name “equi­nox” is derived from the Latin aequus (equal) and nox (night), because around the equi­nox, the night and day are approx­im­ately equally long. It may be bet­ter under­stood to mean that lat­it­udes +L and –L north and south of the Equator exper­i­ence nights of equal length.