Here we are at the winter solstice, the shortest day and longest night of the year. It's a solemn occasion for some, a time of joy for others, meaningful in almost every culture around the world. In some places it coincides with famine, in others it marks the birth of a savior. The People of Two Rivers, as I have named the Hohokam in my series of prehistoric novels, definitely observed the solstices and equinoxes . . . but how?
For my "Tales of the Watermasters" series, a group of specialists named the Skywatchers follow the sun as it shifts through its seasonal round. The Skywatchers tell the people when they can safely plant their first crops in the spring (although the Valley of Two Rivers becomes fiercely hot in the summer and has a long growing season, frost occurs frequently enough in early spring that too-early planting can be disastrous); when to call down the summer rains that enable a second planting; when to offer thanks to the mother-goddess for providing the preservable foods that will carry them through the lean winter; and when to turn back the sun from the darkness of winter to bring the warmer days of spring.
The Skywatchers relied on astronomical observatories such as the one at Mother Sleeping (AKA Hole-in-the-Rock), the Temple of the Mist (AKA Casa Grande Ruins), Spirit Mountain at Serpent Gate (AKA the Pueblo Grande platform mound), rock art at River Shield Butte (AKA Tempe/Hayden Butte) and in the Greasy Mountains (AKA South Mountain Park), and a structure along with rock art north of Serpent Gate (in the Phoenix Mountains).
These ancient observatories suggest that the spring sun-festival of the People of Two Rivers began a few days earlier than the actual equinox, perhaps March 18, and the fall sun-festival began a few days later, perhaps September 25. The sun's position along the horizon may also have given ordinary people a rough idea of when to expect the sun-festivals to occur, as the sun would rise or set in a specific "notch" in the mountains that surround the valley for approximately four days. According to the calculations of avocational archaeologist Ben Mixon, there would be 189 days during the summer period, between the equinoxes, or seven months of 27 days each. During the winter, there would be 174 days, or six months of 29 days each. (See my earlier post about the calendar.)
The historic O'odham people, the inheritors of the Hohokam world, had a twelve- or thirteen-month lunar calendar that began in the summer, whereas I have written the People of Two Rivers as starting their year with a four-day New Fire ceremony at the winter solstice, when the sun is "turned back" along the horizon, marking the lengthening of days. The thirteen moons observed by the O'odham appear to have consisted of seasonal markers important to these agricultural people: hot, rainy, short planting, dry grass, light cold, low cold, backbone (midwinter), rutting/heat (animals), lean (animals), leafless, green (leafing-out or sprouting), yellow (flowering), flowers fading (fruiting).
The O'odham used to celebrate the winter solstice with a four-day ceremony focused on their creation myth, with deities who lived at the solstice points on the horizon. Archaeologist Todd Bostwick, in his Landscape of the Spirits, on the rock art of the Hohokam, has a fascinating discussion of the Hohokam calendar systems.
I had my mother teach me to read when I was four, and I've never stopped. Now I can play with words all day long... it's the best job in the world.