Fall Equinox	This is the time when the sun crosses the Earth's equator moving south. Everywhere on Earth (except at the poles), day and night are the same length (12 hours). In the Northern Hemisphere, this is the beginning of fall.
The globe at the bottom shows the Earth in relation to the sun on the fall equinox. The Earth is not tilted toward or away from the sun. The image below shows where the sun's most direct rays hit on the equinox. After the fall equinox, those strong direct rays will begin to move south of the equator. North America will receive fewer and fewer hours of sunlight.