In the fall, leaves change color and apples and pumpkins are ripe. BrianAJackson/iStock/Getty Images Plus
Meteorological fall arrived on September 1. This is harvest season for many people in the Northern Hemisphere. Apples are ready to pick at orchards and pumpkin patches await visitors. Are you raking leaves yet? Are you enjoying delicious, warm apple cider as the temperature begins to cool? The first day of astronomical fall in the Northern Hemisphere officially arrives September 22 when the Sun crosses the celestial equator going north to south, which is called the autumnal equinox. During an equinox the tilt of Earth’s axis and Earth’s orbit around the Sun are positioned such that the axis isn’t tilting one hemisphere toward or away from the Sun. Direct sunlight shines on the equator, so the length of day and night is nearly equal for both hemispheres.