Although there’s nothing official about it, it’s traditional to say the upcoming March or vernal equinox signals the beginning of spring in the Northern Hemisphere and autumn in the Southern Hemisphere. This equinox does provide a hallmark for the sun’s motion in our sky, marking that special moment when the sun crosses the celestial equator going from south to north. The 2017 vernal equinox arrives on March 20 at 10:29 UTC.
