Every winter I look forward to Earliest Sunset Day. Here in New England, the sunlight drains away with distressing speed in October and November, so I always feel a little warmer inside (even though there are currently 8 inches of snow on the ground) knowing that the sunsets will start getting later and later starting around now in December. In fact, when I went to check my trusty SunGraph program this year, it informed me that Earliest Sunset Day for my location was on December 9th. If you live near me, you too can celebrate the illusion that the days will now appear to be getting longer. Of course once you factor in the dawn, the days don’t actually lengthen until the honest-to-goodness solstice on the 21st.
It’s easy enough to see how ancient astronomers determined the solstice: they watched where the sun rose and set and noted when it stopped moving south and appeared to stand still (sol+stice derives from sun+still). But without accurate timepieces, I wonder how long it was before they realized that the earliest sunset did not coincide with the solstice. My guess is that some clever Greek had it all figured out a few thousand years ago.