Is march 21st a solstice

No, March 21st is not a solstice; it marks the vernal equinox in the Northern Hemisphere, when day and night are approximately equal in length. The solstices occur around June 21st (summer solstice) and December 21st (winter solstice), marking the longest and shortest days of the year, respectively. The equinoxes, including the one in March, signify the change of seasons.