Archaeology: The Eighth Wonder

Boston University Astronomy Professor Gerald Hawkins has a bone to pick with historians who list the seven wonders of the ancient world. It is not that they have picked the wrong wonders, only that their list is too short. Britain’s Stonehenge, says the British-born scientist, is the eighth wonder—a remarkable achievement of primitive man. In a new book, Stonehenge Decoded (Doubleday; $5.95), he explains how he turned to a modern computer to unravel the 3,500-year-old mystery of Salisbury Plain. Stonehenge’s long-kept secret, says Hawkins, is that its vast stone slabs and archways make up a sophisticated astronomical observatory.

Sacrifices & Pageants. Constructed in several stages by late Stone Age and early Bronze Age men between 1900 B.C. and 1600 B.C., Stonehenge’s most prominent features are a 97-ft. ring of 25-ton uprights and horizontal slabs (known as the Sarsen Circle) surrounding five huge trilithons or archways. To build them, primitive Britons had to haul stones weighing as much as 50 tons overland from a quarry 20 miles away. For hundreds of years, archaeologists have probed around and under the structure in a vain attempt to understand what motivated its builders. Charred bones and artifacts convinced some that it had been a mortuary, a crematorium or even a sacrificial altar. The awesome architecture and isolated setting also suggested to others that it had been the scene of religious rites and pageants.

To Astronomer Hawkins, one long-established fact seemed most significant: Stonehenge is oriented so that its axis passes through a 35-ton marker stone and points directly to the spot on the northeast horizon where the sun rises at the summer solstice, the longest day of the year. Stonehenge probably was built, he reasoned, to mark midsummer day.

Solstice & Equinox. Standing among the giant slabs, Hawkins was struck by the way the early architects had limited his exterior view. Looking through one of the narrow trilithons and an aligned archway in the outer ring, he writes, “I felt that my field of observation was being tightly controlled, as by sighting instruments, so that I couldn’t avoid seeing something.” What the ancients were directing his attention to, Hawkins became convinced, was the rising and setting of celestial bodies, perhaps the sun or certain stars or planets. Returning to the U.S. with accurate charts of Stonehenge, he plotted the positions of its center point and of each significant stone, archway, hole and mound, then fed the data into a computer programmed to calculate the compass directions established by 120 pairs of such positions and the points where a line drawn through them would meet the horizon.

The computer yielded some tantalizing results. Many of the Stonehenge alignments accurately pointed to the summer and winter solstice positions of the rising and setting sun and moon —the extreme north and south latitudes reached only on midsummer day and on midwinter day, the shortest day in the year. Thus, the early Britons were able to determine, for instance, that winter had started on the one day a year that the rising sun was entirely visible just on the horizon through two specific, carefully aligned arches. Additional plotting revealed that alignment of other stones had pinpointed equinoctial positions of the rising and setting sun and moon, enabling Stonehenge observers to determine accurately the first dav of both spring and fall. Concludes Hawkins: “Stonehenge was locked to the sun and moon as tightly as the tides. It was an astronomical observatory. And a good one, too.”

Mysterious Circle. Hawkins believes that Stonehenge astronomy was so advanced that its experts had apparently noted a phenomenon undetected even by modern astronomers: eclipses of the moon occur in cycles of 56 years. Hawkins, who inadvertent’v rediscovered the cycle after running Stonehenge eclipse data throuah a computer, immediately associated it with a mysterious circle of 56 “Aubrey” holes that ring the massive arches. He concluded that the holes formed a primitive eclipse computer. By placing a stone in each of six appropriate holes and moving them at appropriate times one hole around the circle, he decided, the Stonehenge astronomers had probably been able to tell accurately the dates when solar and lunar eclipses were apt to take place.

From all this, Hawkins assumes that Stonehenge was the focal point of an early British civilization. It was the calendar by which the Britons planted and harvested their crops, a shrine where they worshiped their gods and buried their dead. It was also a device that priest-rulers could have used to enhance their power. On the day or night that their stone computer predicted an eclipse, they might well have summoned their subjects to Salisbury Plain to observe a spectacle that terrorized most ancient peoples. When the eclipse started, the priests probably intoned the prayers that enabled the sun or moon to escape the blackness.

* The others: the pyramids of Egypt, the gardens of Semiramis at Babylon, the statue of the Olympian Zeus by Phidias, the temple of Artemis at Ephesus, the mausoleum at Halicarnassus, the Colossus of Rhodes and the Pharos (lighthouse) at Alexandria. In some listings, the Walls of Babylon are substituted for the Pharos.