The design of the UMass Sunwheel is
based
primarily on ASTRONOMICAL REQUIREMENTS,
although some aspects of the design will
focus on the Sunwheel as a visual
structure. An essential part of the Sunwheel is
the
CENTRAL VIEWING AREA;
it is from the
center of the Sunwheel that all of the
sunrise and sunset observations and sightings
are made. The STANDING STONES to be used
in the Sunwheel will be placed in a circle
65 feet from the central viewing area. The
stones will be natural granite monoliths,
approximately 2'x4' at the base and 8'
high, each weighing roughly 3 to 5
tons. The 4 stones marking the SUMMER AND
WINTER SOLSTICE
sunrises and sunsets will
each stand 8 feet above ground. For
orientation and symmetry, there will be
standing stones in the
NORTH, SOUTH, EAST and
WEST directions as well. Rather than a
single standing stone in the East and West directions,
there will be 2 standing stones
approximately 2-3 feet apart,
making a
portal. These stone doorways will
also be 8 feet high and located 65 feet from the central
viewing area, marking both the cardinal directions and the EQUINOX
sunrises and sunsets.
In addition to
the standing stones, there will be an
INFORMATIONAL EXHIBIT which is
displayed around the area, describing the
use of the
Sunwheel and explaining the
origin of the cycle in the
Sun's apparent
motion
throughout the year. With this
explanatory information added to the structure,
the
SUNWHEEL IS AN OUTDOOR
EDUCATIONAL EXHIBIT WHICH CAN BE USED YEAR
ROUND BY ANYONE.
The diagram below illustrates the Sun's daily path in the sky
on the solstices and
equinoxes for observers
at mid-northern latitudes.
This diagram illustrates that the Sun rises
to the northeast and sets
to the northwest on the Summer Solstice, while
the Sun rises to the southeast and sets to the southwest
on the Winter
Solstice. Also illustrated is the fact that the Sun is higher in the sky
at noon on the
Summer Solstice than on the Winter Solstice, and that
there are more daylight hours in the summer
than winter. The fact that the Sun is
higher in the sky in the summer, combined with more daylight
hours, is
what causes us to have warm summers. These effects come about because
of the fixed 23.5 degree tilt of the Earth's axis of rotation relative
to the plane of our yearly orbit around the Sun.
In addition to
the SOLSTICE, EQUINOX, and NORTH, SOUTH, EAST, and WEST STONES,
the Sunwheel
will also include a unique feature
-- MOONSTONES.
These additional standing stones, to be next to each of the
solstice stones,
and 1-2' shorter in height, will mark the extremes in the
rising
and setting direction of the Moon. Because of the Moon's
18.6 year cycle,
the next time the Moon will
reach its major
standstill is 2007, and at that time the moonrise and moonset directions
will be toward
the MOONSTONES in the Sunwheel. The locations of these stones
were calculated based
on the tilt of the
Moon's orbit with respect to the ecliptic.
Click below to
see a figure showing the relative locations of the SOLSTICE STANDING STONES and STONE DOORWAYS.