Early astronomers used nothing much more than their eyes, sticks and careful record keeping to construct the first calendars.
Here at Myrtle Street Review, we can use surveillance video as our observatory. In this video, you can spot the winter equinox. What you see is an animation of the camera view at exactly 12:00 noon from October 15, 2008, to February 1, 2009. By watching the direction the shadow moves you can see the earth passing through the Winter Solstice. When the tree shadow is moving the left, the days are getting shorter. When it is moving to the right, the days are getting longer.