Archeologists discover ancient solar observatory in Peru

In the coastal desert of Peru, a team of archeologists from Yale University and the University of Leicester have found what they believe is the oldest solar observatory in the hemisphere to have alignments covering the entire solar year. Their findings were published in the journal "Science."

What you need to know - Conventional View

• According to the archeologists, the ruins at Chankillo, Peru contain 13 stone towers that functioned as a solar observatory.

• The ruins are approximately 2,300 years old, predating the earliest post-Conquest accounts of a detailed solar calendar by 1,800 years and predating similar Mayan structures in Central America by about 500 years.

• According to Spanish records, the Incas used "sun pillars" to maintain their calendar and to time plantings and festivals.

• The towers at Chankillo are of the right height and spacing to align with the sun at various specific times of year. It is the earliest such observatory discovered in the Americas that contains alignments for the entire solar year.

• The entire Chankillo site is about 1.5 square miles in area and also contains a massive fortress.

• Quote: "We have known for decades from archaeological artifacts and documents that [indigenous Peruvians] practiced what is called solar horizon astronomy, which uses the rising and setting positions of the sun in the horizon to determine the time of year.... But we did not know that these practices were so old." - Lead Author Ivan Ghezzi