Venus Cycle
Another important calendar for the Maya was the Venus cycle. The Maya were skilled astronomers, and could calculate the Venus cycle with extreme accuracy. There are six pages in the Dresden Codex (one of the Maya codices) devoted to the accurate calculation of the heliacal rising of Venus. The Maya were able to achieve such accuracy by careful observation over many years. There are various theories as to why Venus cycle was especially important for the Maya, including the belief that it was associated with war and used it to divine good times (called electional astrology) for coronations and war. Maya rulers planned for wars to begin when Venus rose. The Maya also possibly tracked other planets’ movements, including those of Mars, Mercury, and Jupiter.
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