Bob Moler's Ephemeris Blog

Ephemeris for Monday, September 22nd.  The sun will rise at 7:29.  It’ll be up for 12 hours and 10 minutes, setting at 7:39.   The moon, 2 days before new, will rise at 6:54 tomorrow morning.

Welcome to the last, almost full, day of summer.  The Sun will reach the autumnal equinox point in the sky at 10:30 this evening.  At that moment the Sun will cross the celestial equator, a projection of the Earth’s equator, heading southward.  All locations on the earth except two will experience 12 hours of daylight and 12 hours of night.  Well they would if the Earth didn’t have an atmosphere and sunset and sunrise were defined differently.  The two locations that don’t experience equal night, which is what equinox means, are the north pole where the sun will be setting and the south pole where the sun will be rising.  For us in the northern hemisphere daylight hours will be shorter and the Sun will peak lower in the south each day until the December solstice.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

The Earth as seen from the direction of the Sun as it crosses over the Earth’s equator heading south. Created using Celestia.