The September equinox is the autumnal (fall) equinox in the Northern Hemisphere, while in the Southern Hemisphere, it is the vernal equinox, marking the start of spring.

Harvest Moon on October 5

The Full Moon on October 5 is the Harvest Moon in the Northern Hemisphere. For several nights in a row, it almost seems as if there are Full Moons every night. Known as the Harvest Moon Effect, this happens because of the low angle the Moon's orbit around Earth makes with the horizon during this time of year.