<P> An equinox is commonly regarded as the moment in which the plane of Earth 's equator passes through the center of the Sun 's disk , which occurs twice each year , around 20 March and 23 September . This simplified , but incorrect , understanding of Earth 's orbital motion can lead to errors of up to 69 seconds from the actual time of equinox . </P>
<P> An equinox is commonly regarded as the moment in which the plane of Earth 's equator passes through the center of the Sun 's disk , which occurs twice each year , around 20 March and 23 September . This simplified , but incorrect , understanding of Earth 's orbital motion can lead to errors of up to 69 seconds from the actual time of equinox . </P>
what is the date of the autumnal equinox
what is the date of the autumnal equinox
23 September
23 September