The Pleiades (Tianquiztli) are portrayed in the upper left of the document. The other symbols represent other constellations, a meteor or shooting star, the sun, the moon, the eclipses. The image is from the Primeros Memoriales, a sixteenth-century colonial manuscript compiled by Fray Bernardino de Sahagun.
Click on image for full size
Image courtesy of the book 'Moctezuma's Mexico' by David Carrasco and Eduardo Matos Moctezuma. University Press of Colorado, 1992.


The Pleiades were known to the Aztecs as Tianquiztli which means "marketplace." The Aztecs were excellent observers of the Sun, the moon, and the planets.

Time was measured according to the movements of the stars and those of the Sun. Their calendar was based on cycles of fifty-two years. They watched the Pleiades carefully move in the sky to ensure that the world would not end.

At the end of each cycle, a religious ceremony would take place to ensure the movement of the cosmos and the rebirth of the sun. Aztecs believed that they could prevent the demons of darkness from descending to Earth and devouring men, by offering to the gods human sacrifices.

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