A recent Facebook posting referred me to an article about dark matter and how astronomers are mapping dark matter through space by identifying how light distorts as it travels through the invisible web of the dark. Scientists hope that, by mapping dark matter’s distribution through the sky, they can gain a better understanding of this substance and the underlying physics of the universe.

Reading this article reminded me of my recent trip to Peru and the unique Incan astronomy. Most of us are taught that the Incan’s worshiped the sun, and indeed the sun was a deity to the nobles. But beyond that worship, the Inca used their astronomical studies to not only follow the sun, moon and stars, but also to map the dark parts of the sky. They even had a special word for those places: ‘Yana Phuyu’, or dark clouds – the vacant places in the sky.

The Inca believed the Milky Way was a great river and the Yana Phuyu were animals called Pachatira that came from mother earth to drink at its side. These dark clouds were known and tracked across the sky and watched with interest. There was the fox, the black llama with her child, the serpent, the toad, the partridge. Each had their place in the sky and each was watched for signs of what would happen on earth. As the black llama descended from the sky she would lower her head and drink from the oceans to stop flooding. The toad, Hanaptu, rose in the sky, when the toads came out of hibernation, and Azoq, the fox rose during the summer solstice when foxes gave birth. For that was the strength of Inca astronomy, they truly believed ‘as above so below’. They watched the heavens and foretold the seasons and the rains by when certain animals appeared over the horizon or climbed the sky and, according to legends, major ecological events like devastating earthquakes and floods, along with the ages of the world.

But the Inca did more than that. They saw the heavens as a map of their world, with the great river of the Andes, the Rio Vilconota (aka the Urubamba) as the terrestrial version of the Milky Way. They recognized hundreds of holy sites (Huacas) around their empire that often were related to special days of the year and the places where the rising and falling sun was observed.

Today, stories of the skies are still taught to children in Inca villages. In Quechua they teach how the llamas in the fields watch the heavenly llama for news of the rains. They tell tales of the moon and his wife and how the ‘fall’ of the Moon’s wife led to the pumpkin-color of the soil in the Amazon. So though we will never know the true depths of Inca astronomical knowledge – too much was lost to the Spanish conquest – we do know that the Inca were much like the scientists of today: They mapped the heavens as a means to understand the connections of the universe around them.