In Search Of... Season 3 # 11, Indian Astronomers

Long before the first explorers came to America in Southern Illinois once stood a temple, home to 1.000 people. An excavation of wooden pole-remnants revealed a giant circle. It served as a calendar being placed exactly according to astronomic measures.
Men and women have been sacrificed to ensure their priest a safe journey. (See: Ancient Mysteries: The Mayans who have had the earliest written language.) The Khahokia measurement was nearly identical to the measurements of the Mayans. Did the Mayans travel north?

The Anasazi, a desert tribe, erected stone towers in the desert to observe the heavens. Some windows line up with the rising moon. This area lies between Khakokia and the Mayan buildings.
The observatory at Casa Grande also shows similarities to the Mayan observatories. A pueblo in Chaco Canyon also revealed exact astronomic knowledge. A fire-ceremony is known to be celebrated by the Anasazi and the Chaco people. There was trade between distant cultures and exchange of knowledge. They watched the stars and used them in precisely the same way.
The turquoise found in the American South West and in Mexico were examined and showed that there was trade between the peoples though they lived thousands of miles apart.