In the Northern Hemisphere, the spring equinox usually falls on March 19, 20, or 21. From this point until the summer solstice in June, the days gradually become longer and the nights shorter. Because the Earth’s orbit is slightly irregular, the exact timing of the equinox shifts by a few hours each year. The Meteorological Definition
For astronomers, the start of spring is defined by the position of the Earth in relation to the sun. This is known as the Vernal Equinox. This event occurs when the sun crosses the celestial equator, resulting in nearly equal amounts of daylight and darkness. what month is spring time
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