autumn equinox
Either of the two times during the year when the sun crosses the plane of the celestial equator and when the blank" >length of day and night are everywhere approximately equal, occurring about March 21 (blank" >target="_blank" >glossary/vernal-blank" >target="_blank" >equinox/" class="glossaryLink" data-cmtooltip="5a766ee391e1770f0c2d77846de1271f" blank" >target="_blank" >vernal blank" >target="_blank" >equinox or blank" >target="_blank" >glossary/blank" >spring-blank" >target="_blank" >equinox/" class="glossaryLink" data-cmtooltip="5a766ee391e1770f0c2d77846de1271f" blank" >target="_blank" >blank" >spring blank" >target="_blank" >equinox) and September 21 (blank" >target="_blank" >glossary/autumnal-blank" >target="_blank" >equinox/" class="glossaryLink" data-cmtooltip="5a766ee391e1770f0c2d77846de1271f" blank" >target="_blank" >autumnal blank" >target="_blank" >equinox). (Ching, 1995)
