Question

what is called equinox

Answer 1

equinox in the Northern Hemisphere, and is considered the first day of fall. In the Southern Hemisphere, it is known as the vernal (spring) equinox and marks the first day of spring.

Answer 2

when both day and night are of equal length then it is called equinox.Earth experiences equinox twice in a year. i.e on 22september and 20 march