How long does the equinox last?

During the equinox the day and night are of the same length, 12 hours, all over the world. This is because on the two equinoxes, the tilt of the Earth’s axis is perpendicular to the Sun’s rays, while on any other day of the year, either the Southern Hemisphere or the Northern Hemisphere tilts a little towards the Sun.

Further Readings-

1. Difference Between Summer and Winter Solstice
2. Motions of the Earth

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