Home > Concepts, Ephemeris Program > 12/08/2017 – Ephemeris – The earliest sunset of the year is tomorrow night

12/08/2017 – Ephemeris – The earliest sunset of the year is tomorrow night

December 8, 2017

Ephemeris for Friday, December 8th. The Sun will rise at 8:06. It’ll be up for 8 hours and 55 minutes, setting at 5:02. The Moon, 2 days before last quarter, will rise at 11:04 this evening.

In thirteen days we will have the shortest day in terms of daylight hours. But the change isn’t uniformly distributed in the morning and evening. Tomorrow evening we will have the earliest sunset. Sunset times have been within the same minute for the last few days and will continue for the next few. The latest sunrise will occur on January second. The reason is that the Sun is traveling faster eastward than average, so the Earth’s rotation takes a little longer each day to catch up with it. Near the solstice the Sun is at a higher latitude, where the longitude lines are closer together, also the Earth is nearing its closest to the Sun, so moves faster its orbit adding to the effect. The effect exists in June but isn’t as noticeable.

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


I had more complete thoughts about earliest and latest sunrises and sunsets earlier this year: https://bobmoler.wordpress.com/2017/03/13/03132017-ephemeris-more-thoughts-about-yesterdays-time-change/. Check the addendum.


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