It’s complicated. Confused?
You will be!
Many people celebrate a whole day, usually March 21, as the March equinox. However, it occurs at a specific moment in time and its date at any given location is determined by the exact instant when the Sun is overhead at the Equator. It is not the same time every year either, because the earth does not revolve around the sun in an equal number of days It gets later every year until a leap year resets it.
This year the equinox is 20th March at 21:58 GMT. Today, day and night are twelve hours each, sunrise is at the same time AM as sunset is PM.
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