A solstice is a point during the Earth's orbit around the sun while during an equinox, the sun is at its nearest point from the Equator. Another difference is that a solstice takes place on June 21 and December 22, while an equinox takes place on March 20 and September 22. One more difference is that during the summer solstice, the days are longer and in winter solstice, the nights are longer. For an equinox, the duration of day and night are both equal.
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