Mexico’s Ancient Astronomers
By Ralph Graves
March 2005 Guadalajara-Lakeside Volume 21, Number 7

     Do you know which sign you were born under? Have you checked your horoscope lately? If you believe the heavenly bodies influence your daily life and future, you have a lot in common with the ancient Mexicans. Their celestial observations foreshadowed today’s astrology, astronomy and the modern calendar.
     From darkened observatories, without the aid of telescopes, the early Mayans and other pre-Hispanic cultures measured, calculated and mapped the movements of the sun, moon and stars utilizing a variety of methods. Lines of sight were devised and stone structures erected to serve as anchor points. The careful measurement of shadows and a refined numbering system were other important elements in early astronomy. These early scientists not only devised a yearly calendar of 365 days, but knew how to correct it periodically, much as we do with our leap years.
     As with ancient cultures elsewhere, the study of the heavens in early Mesoamerica grew from the need to plan the sowing and harvesting of crops. The growing of corn, beans, squash and chile peppers in a harsh environment required a knowledge of the cycles of Mother Nature, so the early Mexicans looked to the heavens for guidance. What ensued was an intensive study of the skies and ultimately, a correlation of the movements of celestial bodies with the regular cycles of time. Planting, harvesting, even fishing and hunting became linked with prominent astronomical events.
     Such vital information soon became the sole province of the religious class. Observatories began to form an essential element in the many religious centers of the time and in the hands of the priests, guidance on practical matters, such as when to sow and reap, became intermingled with invocations to the gods, sacrificial ritual and seasonal celebrations.
     Recurring celestial events, including the appearances of comets and meteor showers, were believed to be under the influence of specific deities.
     Tables were devised of these occurrences, leading to an annual calendar. The year itself was partitioned to coincide with the cycles of agricultural activities, and the months and even the days were assigned to specific gods.
     The Mayan calendar of 365 days was grouped into eighteen 20-day months plus a five-day “correction” period at the end of the year. This left-over period was regarded as useless at best, and thought to be unlucky. Some later cultures regarded these days as a period of evil when any misfortune in a person’s personal life would become permanent. It was believed those born during this period were destined to be plagued with bad luck and would grow up to be poor and miserable.
     According to the Spanish Conquistadores, the Aztecs observed the end of the five-day period with a cleansing ceremony of fire. During the period, the citizens of Tenochtitlan would clean their houses, smash old pottery and discard various household items. All fires were extinguished and images of the gods were destroyed or tossed into the lake. On the eve of the new year, priests would dress up in the vestments of the gods and parade up a mountain overlooking the city where they would attempt to make fire by rubbing sticks together. At midnight, all eyes were focused on the mountain top, for if the priests failed, it would surely signal a coming disaster.
     As soon as the new fire was made, a huge bonfire was lit, which could be seen for miles in all directions. Teams relayed torches lit from the fire to various temples throughout the city where the people could come and light torches for their new household fires. The days following were celebrated with feasting and the preparation of new clothes, jewelry, household goods and religious icons.
     As they became more skilled in astronomical observation and time recording, the early priests began to interpret special combinations of day signs and numbers to be of religious significance. Thus the ancients came to believe their everyday lives were influenced by the cosmos. Some days were good days and others were evil. The day a person was born determined his or her temperament, disposition and behavior throughout a lifetime. Astronomy became an integrated system linked with religion and it touched every aspect of life, from daily routine to solemn rituals.
     In effect, these early Mexicans had developed their own version of the zodiac, perhaps much more complicated than that of today, but no less meaningful. So, if you are a follower of the zodiac and believe your destiny is dictated by the heavens, you’re continuing an age-old tradition. Good luck.