whats equinoxes?

Answer 1

The first days of spring and autumn when day and night are of equal length at all latitudes (except the poles) and the noon sun is directly over the equator.
www.ametsoc.org/amsedu/WES/glossary.html

Either of the two times when the sun crosses the equator-autumnal equinox is the first day of fall; vernal equinox is the first day of spring
library.thinkquest.org/5405/Glossary.html

In astronomy, an equinox is defined as the moment when the sun reaches one of two intersections between the ecliptic and the celestial equator.
en.wikipedia.org/wiki/Equinoxes

Answer 2

Equinoxes are the two days when the sun's rays fall directly on the Equator at noon.These two days are March 21 and September 23.
As the sun's rays are directly on the Equator, the Circle of Illumination cuts all latitudes equally and all places on Earth experiences 12 hours daylight and 12 hours darkness..i.e. equal days and nights.
March 21 is called Spring Equinox as on this day the Northern Hemisphere is getting warmer after the long winter nights...and is enjoying the Spring season.
September 23 is called the Autumn Equinox as the Northern Hemisphere is cooling down after the long summer days and is experiencing Autumn.

Answer 3

an equinox is when day and night are the same length in time. It happens twice every year on March 21 and September 22.

Answer 4

Equinoxes means when the sun is overhead at the equator on September 23rd and March 21st Autumn season and Spring Season respectively. This time is equal day and night all over the world that is sunshine and darkness.

Answer 5

When days and nights have equal durations its called equinox