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Archive for July 23, 2026

Ephemeris: 07/23/2026 – Our location in the Eastern Time zone

July 23, 2026 Comments off

This is Ephemeris for Thursday, July 23rd. Today the Sun will be up for 14 hours and 59 minutes, setting at 9:18, and it will rise tomorrow at 6:20. The Moon, 2 days past first quarter, will set at 1:36 tomorrow morning.

Continuing my discussion about daylight savings time: In theory time zones are supposed to be centered on longitude meridians 15º apart, starting at 0° through Greenwich Observatory in England and proceed eastward and westward. our time meridian for Standard Time (75º west longitude) runs through Philadelphia, Pennsylvania, far to the east. The central standard time meridian runs down just east of Ironwood, Michigan. Most of us in the western lower peninsula are between 85 and 86° west longitude, meaning that we are already from 40 to 45 minutes behind our time meridian in Philadelphia and Eastern Daylight Time we are an hour and 40 to 45 minutes behind our daylight time meridian which is out in the Atlantic Ocean at 60° west longitude.

The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

US time zone map for daylight saving time.
US time zone map for daylight saving time. I’ve added the approximate locations of the time meridians where, under standard time, the sun averages being due south at noon. there was not room for the EDT/AST meridian. It does touch the eastern end of Nova Scotia. Map credit: nist.gov.

Categories: Concepts, Ephemeris Program, Time Change