Home > Concepts, Ephemeris Program, Winter Solstice > 12/21/2015 – Ephemeris – Except for 12 minutes today is the last day of autumn.

12/21/2015 – Ephemeris – Except for 12 minutes today is the last day of autumn.

December 21, 2015

Ephemeris for Monday, December 21st.  The Sun will rise at 8:16.  It’ll be up for 8 hours and 48 minutes, setting at 5:04.   The Moon, 3 days past first quarter, will set at 4:50 tomorrow morning.

Here we are at the mostly last day of autumn.  The last 12 minutes will be the start of winter.   The winter solstice will occur at 11:48 this evening, here in the Eastern Standard Time Zone.  Next year winter will start 18 hours earlier.  The reason is that next year is a leap year and the addition of an extra day will push all the solstices and equinoxes back by about 18 hours.  Why only 18 hours?  18 hours is three-quarters of a day, and by this time next year we will have used up a quarter of that adjustment already.  The Earth takes approximately 365 and a quarter days to orbit the Sun, so a day is added every 4th year, except century years not divisible by 400.  I’ll discuss more about the implications of the solstice tomorrow.

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

Addendum

The Earth near December solstice

Not quite the solstice, this is the Earth on December 16th, 2015 taken by the EPIC camera on the DISCOVR spacecraft at the Sun-Earth L1 point, some 1.5 million miles (1 million km) from the Earth.  Credit:  NOAA.

 

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