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Shortly after noon the next couple of days, a dagger of sunlight will slide across a bluff on the banks of the Concho River at Paint Rock, Texas. As the Sun stands highest in the sky, the dagger will stab through the heart of a several-hundred-year-old pictograph.
The red painting depicts a shield — a possible symbol for the Sun. The dagger of sunlight crosses the shield only around the winter solstice, which is coming up tomorrow. It’s the shortest day of the year in the northern hemisphere, when the Sun stands farthest south in the sky.
The Paint Rock site contains hundreds of pictographs, which extend about half a mile along the bluff. Some of the pictures clearly depict the Sun.
A couple of decades ago, the site owners heard about other rock-art sites with alignments to the solstices or equinoxes. They contacted a University of Texas astronomer, who suggested they watch the site at local noon on these dates.
On the winter solstice of 1996, they discovered the dagger of sunlight crossing the shield. Later study confirmed that the alignment probably was intentional — the shaft of light shines through a crack in the rocks only at the solstice.
Native cultures may have painted the symbol to indicate the solstice. If so, then they probably held rituals on the solstice to confirm the power of the rulers, and to entice the Sun northward — bringing warmth back to the Texas hills.
More about the solstice tomorrow.
Script by Damond Benningfield