Professor’s Calendar Is Set in Stone

Even with big, powerful earth-moving machines, it isn’t easy to build a calendar of standing stones to mark the seasons.

But using an ancient design and 56 tons of Berkshire granite, Judith Young has created a teaching tool for a new millennium with her massive modern stone circle. It sits outside the football stadium at the University of Massachusetts.

The rough granite blocks are labeled to mark the rising and setting of the sun on the solstices and equinox, as well as the extremes of moonrise and moonset.

Young’s sunwheel, a stone circle 130 feet in diameter, has evolved over the past six years. It is no mere replica of Stonehenge, the 4,000-year-old stone circle that rises from Britain’s Salisbury Plain, aligned along the rising of the sun at the summer solstice.

Her standing stones are precisely aligned to Amherst’s latitude to allow university students, schoolchildren and just ordinary folks to explore the mysteries of the universe.

“It’s a way to teach people about the sky and to love science and the universe without using electricity or computers,” said Young, an astronomy professor who has developed special lessons for middle and elementary school teachers using the sunwheel.

“This isn’t something you find in a book,” she said. “It was the first science.”

The most popular times for visitors--about 3,000 have visited in the last year--are the midsummer and midwinter days. The solstices mark the times when, because of the earth’s 23.5-degree tilt, the sun’s path seems farthest from the equator. In the Northern Hemisphere, the summer solstice, June 21, is the longest day; the winter solstice, Dec. 21, is the shortest.

On a winter afternoon with dark shadows stretching across the great stones and the frost-seared grasses in a field outside the football stadium, it’s easy to understand why the solstices were so important to ancient civilizations.

“The word solstice means to stand still,” Young said. “For two weeks around the summer and winter solstice, the sun appears to stand still--rise and set in the same spot. They couldn’t miss it.”

Last year, for example, the sun set and rose on the university’s solstice stones from Dec. 13-29.

In contrast, the spring and fall equinoxes, which mark the times when day and night are of equal length, last only a few hours, Young said.

Young’s first sunwheel was made of 1- and 2-foot-high boulders. Then, armed with a $35,000 National Science Foundation grant, she began building the existing stone circle.

She admits she developed a bit more respect for the ancient calendar-makers. The first thing she discovered is that most modern quarries produce smooth, shaped stones, not rugged, natural boulders like those used by ancient monument-builders.

She finally found the stones at the small Chester Granite Co. in East Otis, about 45 miles away. The largest is 10 feet high, weighs 7,000 pounds and marks sunrise on the summer solstice. The smallest are the 6-foot-high stones that mark the moon’s 18.6-year cycle. The next time the moon, because of the tilt in its orbit, will appear to reach a major standstill is 2007, she said.

The ancients handled the problem of the heavy stones settling and knocking their calendars out of alignment by choosing boulders big enough so they could bury the base deep in the earth.

“I couldn’t afford that much stone,” Young said.

To keep her 12 stones in trim, Young had 4-foot-deep holes dug for each one. The holes were lined with a water-permeable fabric and filled with some 51 tons of crushed stone. A 2-foot stainless-steel pin and a coating of modern epoxy anchored each stone to a foot-thick granite base.

Even with a modern crawler excavator and the help of civil engineering professors, it took four days to erect the stones.

“The only easy part was calculating where to place them,” Young said.