At noon on the winter solstice, at 12 o’clock solar time, the shadow passes the left edge of the stone.
The animation shows the movement of the shadow on the winter solstice a little after 12 o’clock solar time and nearly 3 minutes ahead:
The stone leaned slightly when the photos were taken in 2008, which may explain why the passage was shortly after 12 o’clock solar time when the sun stood at about 182°. Note that the shadow’s shape matches the shape of the far-stone.
Today the stone’s tilt has further increased causing the shadow´s passage no longer fit nearly as well as the animation shows. Recent measurements made in May 2014 show that the tilt today is about 27° compared with 13° in 2008.