The sky has been a fascination for ancient cultures throughout history. The sky holds the sun, which provides light during the day and gives life to the crops; the sky also provides the night filled with stars and the moon. In the Mesoamerican culture, the sky was significant because they represented different deities who were to be respected through offerings and temples dedicated to them. For example, the Mayan creation story, the Popol Vuh, refers to 2 brother deity’s who defeated the Gods of the underworld and became the sun and moon. Mayan civilization had great advancement in their time. They had an advanced calendar system like ours today, they had a 360-day cycle as well as a unique 260-day lunar cycle called the tzolkin, which is not found anywhere else in the world. Living a cyclic life, they based their life on a 52 year long count which was when the 260-day lunar cycle and the 360-day cycle started at the same time. The Mayan understanding of Venus started as early as the second century A.D. according to the Stela 1 at the site of La Mojarra. The planet Venus, which is known as the Evening Star in the west, disappears and rises in a heliacal fashion as the Morning Star in the east. Venus is the bright object in the sky after the sun and moon. Venus has a 584-day cycle, which would have taken a century or more of diligent observation to produce a reliable pattern that could be used to make accurate predictions. Venus had a great significance to the Mayan people because the position of Venus represented different deities and could represent a time of war and conquest.
The Grolier Codex was discovered in 1964-1965 in the mountains of Chiapas and later purchased in 1966 by Dr. Josuein, a collector of pre-Columbian art. The Grolier Codex discovery is very important because it gives insight into Mayan pre-conquest history and because the Codex is one of four pre-conquest Mayan codices to survive inquisitions and the auto de fé that Friar Diego de Landa initiated in 1562. 1562, he gathered Mayan Codices and idols of worship and burned them because they were seen as lies and superstitions of the devil. The discovery of the 11-page fragmented codex dates to A.D. 1230 +/- 130 years after a radiocarbon test on the paper. Since the first appearance of the Grolier Codex, several independent Mayanists concluded that the Codex is a portion of a 20 page Venus almanac. This conclusion was reached because the Grolier Codex shares the same basic calendrical structure as the Dresden Codex another pre-conquest Mayan Codex. From the Dresden Codex, we can compare the Venus pages with the pages of the Grolier. The Dresden divides the 584-days cycle into four sections that mark the rising and disappearance of Venus, with each section representing a different God. The Mayan calendrical astronomers made sure to align and coordinate cycles of time to create a greater cycle period. For example, if the Venus cycle of 584-days aligns with the 360-day cycle and the 260-day lunar cycle then after two calendar rounds which are 52 years each the cycle repeats, “this is the basis for the Venus calendars found in both The Dresden and Grolier Codices”.
Even though the Grolier Codex is not complete and is not in the best condition, it gives us a good insight into Mayan history in the post classic era (1000 CE–1697 CE). The Grolier Codex shows us that Venus was more than just the rising star. Its movements were well understood and held significant cultural importance.