The separation of day and night at Winter Solstice 2015.
I'm posting this at 8:48 P.M. PST (4:48 UT, December 22), the very moment of the Winter Solstice. The sun, from our viewpoint on this spinning globe, has reached as far south as it will go, and is now beginning to move back north. We in the Northern Hemisphere have made it through the darkest time of the year. Now, this minute, the journey back to light and warmth, a long, beautiful journey, has begun.
Have a great trip.