"The influences of astronomy on ancient cultures".
During ancient times South America was made up of 4 distinct tribal groups, those being The Mayan's.
The Inca's.
The Aztec's and .
The Olmec's.
Between them some of the most amazing astronomical discoveries were made. Time was kept (similar to ours) through use of astronomical measurements, such as earth's orbit of the sun and earth's rotation on the north south axis. Structures have been built that represent earth's alignment with various stars and planets in our galaxy. These cultures maintained accurate measurements of many aspects of our universe from star placement to time.
The Mayans.
The Maya Calendar.
The Mayans discovered ways to measure time through the universe in 500 BC (approx). Days were counted in groups of 1, 20 and 360. The first 2 were chosen for obvious reasons (20 because it is the amount of fingers and toes a person has), 360 they used because it is the approximation of a lunar year (365.2425). The Mayan Calendar was counted in 13 groups (13 x 20 = 260), this is the approximate length of 9 lunar synodical months. A "Haab" which featured later in Mayan existence was a measurement of 365 days, an even closer approximation of a lunar year. Eventually a Mayan calendar was formed which took advantage of these discoveries. A "week" was a measure of 20 days, then a year was a measure of 18 of these weeks and a special week made of 5 days and called "Wayeb". This came to a grand total of 365 days. .
Venus.
Venus was the astronomical object of greatest interest for the Mayans. They thought it was more important than the Sun. They watched it carefully as it moved through its stations--it takes 584 days for Venus and the Earth to line up in their previous position as compared to the Sun. It takes about 2922 days for the Earth, Venus, the Sun, and the stars to agree. .
During the 584 day period Venus will start by disappearing from Earth for 8 days (approx), this is called inferior conjunction.