Calendars: The sun was very important to the Anasazi. The Anasazi
built many structures that helped them measure the time of the year. These
structures were used as calendars.
One of these structures was at Casa Rinconada, where ledges were
built in the wall in relation to the sun's movement at the solstice
and the equinox.
The solstice occurs when the sun is the farthest from the equator.
This happens two times a year, once in the summer and once in
the winter. The summer solstice is the longest day of the year
and the winter solstice is the shortest day of the year in the
The equinox occurs when the sun crosses the equator. The equator
is an imaginary line around the Earth that is the same distance
from the North and South Poles. It divides the Earth into the
northern and southern hemispheres. When this happens, the length
of the day and night are equal. This also happens twice a year.
Casa Rinconada has a window in the northeast wall and another
in the southeast wall. The inside wall of the kiva has many niches
equal space apart. Depending on the time of the year, the sun
will shine through the window and illuminate certain ledges in
the wall. Each ledge, or niche, represents a position of the sun's
light at different times of the year. Casa Riconada is also a
kiva, a place for prayer and religious celebrations.
Another sun-watching station was at Pueblo Bonito. Two windows face
toward the winter-solstice sunrise. Researchers believe that the Anasazi
used one of the windows to anticipate the coming of the solstice.
Fajada Butte, a large butte at one end of Chaco Canyon, has a series
of parallel rocks that serve as a sun and moon calendar. A butte
is a hill that rises swiftly from a flat area of land; it has
steep sides and a flat top. When sunlight passes between these
rocks, it creates a dagger of light against a spiral carved on
the cliff beyond the rocks. This "light dagger" appears
on the cliff for about 20 minutes a day during the solstice.
Experts believe the Anasazi built these light markings as a symbol of
their knowledge of the sun and the seasons. Priests used these structures
to mark the movement of the sun.
Researchers also discovered an Anasazi cave that marks the occasion
of a lunar standstill, a moon phenomenon that happens every 18.61 years.
The moon's distance from the horizon varies each month, moving north
and then south. When the movement from one moon phase to the next is the
greatest, it is called a major lunar standstill. When it is the least,
it is a minor lunar standstill.
A stone arch was just outside the Anasazi cave. As the moon rose on
the night of these standstills, one bright moonbeam passed through the
arch and illuminated a spiral carved on the floor of the cave.
Knowledge of occurrences like the lunar standstill was important to
Anasazi leaders because it allowed them to organize the calendar of both
religious and practical events.
The Pueblo community still keeps track of the calendar by observing
the movement of the sun.
Solar calendar devices were made to indicate proper times for ceremonials
and other important events. In particular, the solstices were regarded
as special occasions and many of the calendar markers were geared to indicate
precisely when a solstice would occur. At Hovenweep Castle, an ancient
Pueblo ruin, a room acts as a solar calendar. Several "ports"
or holes cut into the walls of this room align with the rays of the sun
at particular times and indicate the summer and winter solstices and the
spring and fall equinoxes.
The Hopi also track the movement of the sun. A Hopi priest was
expected to predict the time of the solstices, the two times of
the year when the sun is furthest from the equator. The priest
would go to a sun-watching station to observe the sun as it slowed
its path prior to the solstice. One of these sun-watching stations
consisted of a flat stone with a sun face carved on top and each
of the four quarters marked on its sides. The priest would sit
on it and carefully sight the nearest distinct peak or valley
where the sun would make its last visible slowdown prior to winter
or summer solstice.
This sighting took place a few days before the solstice so that the
people could have time to prepare for the ceremony. The winter solstice
ceremony, for example, lasts nine days, and its announcement is made four
days in advance.
It was important for the Hopi to know when the solstice would
occur so that they could offer sacrifices for the health of their
crops. If they were too late, they believed their crop might fail.
In addition to watching the sun in order to predict solstices, the Sun
Chief also set the planting calendar according to the movement of the