When we talk about the history of astronomy, most people think of names like Galileo, Newton, Copernicus, or Aryabhata. But very few know that ancient American civilizations, such as the Maya, Inca, and Pueblo, also possessed a profound understanding of the heavens. The only difference was that they didn’t record this knowledge on paper but inscribed it on the earth, mountains, stones, and temples.
For these cultures, astronomy wasn’t a separate subject but the very foundation of daily life. When the sun would rise, when the rains would come, when to plant crops, and when to celebrate festivals—all of this was determined by the movements of the sky. The structures they built still stand today as proof of their precise understanding of time and the cosmos.
Chaco Canyon: When a City Became an Astronomical Instrument
Located in New Mexico, Chaco Canyon was not just an ancient city but also functioned as a vast astronomical laboratory. The Pueblo people who lived there constructed buildings in such a way that they could track the movements of the sun, moon, and stars.
The walls of Pueblo Bonito, the largest building, are oriented with such precision that they accurately indicate the cardinal directions: east, west, north, and south. This demonstrates their deep understanding of the Earth’s rotation and the position of the sun. On specific days of the year, sunlight would strike these walls at particular angles, allowing the people to understand when the seasons were changing.
Fajada Butte and the Mysterious Sun Dagger
Fajada Butte, located near Chaco Canyon, is a tall mesa where sunlight passes between three stones and illuminates spiral petroglyphs below. The position of this light changes throughout the year.
On the summer solstice, the light passes directly through the center of the spiral, and in winter, it shifts to the edge. This allowed the people to determine the time of year without a calendar. This technique was so advanced that even today’s scientists are amazed by it.
Chankillo’s Thirteen Towers and the Sun’s Journey
Located in Peru, Chankillo is a unique site where 13 stone towers stand in a straight line. As the sun rises and sets, it appears in different positions between these towers.
This allowed people to determine the date with an accuracy of two or three days. It demonstrates the sophisticated understanding that South American civilizations had of the sun’s annual movement and their ability to translate this knowledge into stone structures.
The Mayan Civilization and the Serpent of the Sun
The El Castillo pyramid at Chichen Itza in Mexico is the most famous example of Mayan astronomical knowledge. On the equinoxes, sunlight creates the shadow of a giant serpent on the steps, appearing to descend from the top.
This spectacle was not merely for aesthetic purposes. It signaled the beginning of a new agricultural cycle. The sun itself told the people when it was time to plant or harvest.
The Moon, Stars, and Long Time Cycles
The Chaco civilization understood not only the sun but also the moon’s 18.6-year cycle, known as the lunar standstill. Very few civilizations in the world recognized this cycle, but the Chaco buildings tracked it.
The people of South America considered the dark areas of the Milky Way as constellations, such as the Great Llama. This shows how unique their perspective on the cosmos was.
Why is all this missing from history books?
This knowledge was long overlooked because it was not written down. It was embedded in stones, images, and oral traditions. European historians did not consider it scientific, and colonialism suppressed these cultures.
Conclusion
Ancient American astronomy teaches us that humans understood the sky even without telescopes and computers. This knowledge, hidden in stone, still tells us today that science and nature were never separate.
