Hi Larry,

The Moon was important to the Inca people and was known as the wife of the Sun. Both of these, the Sun and Moon, were said to have originated from Lake Titicaca, on the border between Peru and Bolivia. The Sun came from the island of Titicaca (now called Island of the Sun), the Moon from the island of Coati (now called Island of the Moon). The Incas built large temples on both islands, but they did not "study" the Moon (or Sun) in the way that we think today, they worshipped in these places. Additionally, in Cuzco, which was the capital of the Incan empire, there was a large building called the Coricancha that housed many temples in which the Sun, Moon, the Stars, Thunder, the Rainbow, and the God Viracocha could be worshipped.

However, the Incas, like most peoples from around the world, probably used the Moon to tell time and had a twelve "moonth" year. Keeping the calendar was done by state-appointed "astronomers" whose job it was to watch the skies. In addition to looking at the Moon, they observed specific constellations and patterns of stars (the Pleiades were very important to them) and used alignments of the Sun to places in and around certain buildings (temples or "observatories") to determine when it was time to plant or harvest crops, and when the equinoxes and solstices were about to occur.

I hope this helps a bit!