|Sep 23, 2019||Autumnal equinox 2019||Northern Hemisphere|
|Sep 22, 2020||Autumnal equinox 2020||Northern Hemisphere|
Significance: An equinox occurs when the plane of Earth's Equator passes the center of the Sun. These are the only two times when the Sun is at zenith over the Equator. The subsolar point crosses the equator, moving southward at the September equinox.