Spring Equinox

The Spring Equinox arrives between March 20 and 21. By that time spring is half over. On this day, because the sun shines directly on the equator, it has equal daytime and nighttime hours. It's after this day that daytime in the Northern Hemisphere grows longer and nighttime gets proportionally shorter.

Chinese ancients plotted their routes and determined the season according to observations of the Big Dipper. On a spring night between 21:00 and 22:00, the handle of the asterism points to the east.