Why is it so dark? when does the sun come back?

 Wait!   Dec. 5 is the earliest sunset; the shortest day and longest night is on December 21 (sometimes dec. 20 or 22) and the latest sunrise isn’t until Jan. 6?  How can that be?

My friend, Bill has suggested the twin holidays of “Quitzel” for December 5 and “Startzel” for January 6.  I call the time between these dates “the Pit”, it is our time with the most depressing days of darkness.  But the apparently random dates and disconnect from our clock time?  Have you ever seen the asymmetrical figure eight on a globe?  That’s the analemma.  You can make one by marking the tip of the shadow from a short pole at 12:00 noon every few days for a year (here’s a link to Wikipedia:  https://en.wikipedia.org/wiki/Analemma).  So, the length of daylight changes throughout the year, and 12 noon isn’t even in the middle of that day!

Our orbit isn’t a perfect circle, and the sun isn’t in the middle of it.  The reason for the asymmetry in daylength around 12:00 noon and the date of the solstice is the asymmetry of earth’s orbit and the acceleration of our planet as it approaches its nearest to the sun at perihelion on Dec. 20, 21, 22 (date dependent on where we are among non-leap years and leap year).  Remember, our 12:00 noon is a construct defined by our steadily running clock, and a year is 365.24 days long.  The length of daylight from the sun isn’t steady.  Our orbit adds one whole day/night cycle during our year.  How much light time each day is changed depending on where we are in our orbit.

The velocity of Earth is at its maximum at the point of perihelion, therefore the approximately (average) 12 hours of light in a day due to Earth's rotation gets changed by the greater fraction of Earth's progress in its orbit during that 24-hour period of clock time (more gets done on the orbit per "day".  Of course, this is complicated by the fact that the actual "sun day" is also changed because the angle toward the sun is changing rapidly as 12:00 noon rolls around...  “Straight up at the sun at noon is changing, we’re moving perpendicular to that direction.  It is further complicated because it is the point in time in which Earth's acceleration (angular momentum) is greatest which brings relativistic time dilation into its maximum.  Even time isn't symmetrical throughout the year! 

The 23.5-degree tilt of Earth’s axis makes all the numbers different dependent on how far you are from the equator… but that’s another problem. 

 Do do do do do, up ahead! there's a signpost... you're in the Twilight Zone.