section_path: Astronomy
section_name: Astronomy
paragraph_text: Astronomy
  
  The famous astrologer John Dee used an Aztec obsidian mirror to see into the future. We may look down our noses at his ideas, but one may be sure that in outlook he was far closer to a Maya priest astronomer than is an astronomer of our century.
  
  The Maya made meticulous observations of celestial bodies. This information was used for divination, so Maya astronomy was essentially for astrological purposes. Although Maya astronomy was mainly used by the priesthood to comprehend past cycles of time, and project them into the future to produce prophecy, it also had some practical applications, such as providing aid in crop planting and harvesting. The priesthood refined observations and recorded eclipses of the sun and moon, and movements of Venus and the stars; these were measured against dated events in the past, on the assumption that similar events would occur in the future when the same astronomical conditions prevailed. Illustrations in the codices show that priests made astronomical observations using the naked eye, assisted by crossed sticks as a sighting device. Analysis of the few remaining Postclassic codices has revealed that, at the time of European contact, the Maya had recorded eclipse tables, calendars, and astronomical knowledge that was more accurate at that time than comparable knowledge in Europe.
  
  The Maya measured the 584-day Venus cycle with an error of just two hours. Five cycles of Venus equated to eight 365-day haab calendrical cycles, and this period was recorded in the codices. The Maya also followed the movements of Jupiter, Mars and Mercury. When Venus rose as the Morning Star, this was associated with the rebirth of the Maya Hero Twins. For the Maya, the heliacal rising of Venus was associated with destruction and upheaval. Venus was closely associated with warfare, and the hieroglyph meaning "war" incorporated the glyph-element symbolizing the planet. Sight-lines through the windows of the Caracol building at Chichen Itza align with the northernmost and southernmost extremes of Venus' path. Maya rulers launched military campaigns to coincide with the heliacal or cosmical rising of Venus, and would also sacrifice important captives to coincide with such conjunctions.
  
  Solar and lunar eclipses were considered to be especially dangerous events that could bring catastrophe upon the world. In the Dresden Codex, a solar eclipse is represented by a serpent devouring the kʼin ("day") hieroglyph. Eclipses were interpreted as the sun or moon being bitten, and lunar tables were recorded in order that the Maya might be able to predict them, and perform the appropriate ceremonies to ward off disaster.