Pyramid Quest (17 page)

Some of the original facing blocks at the base of the north side of the Great Pyramid. Photograph courtesy of Robert M. Schoch.

It is apparent that building the Great Pyramid didn’t require helicopters, levitation, extraterrestrial help, or divine intervention. An organized, highly motivated civilization using tools as basic as water levels, copper chisels, dolorite balls, and levers was capable of building the Great Pyramid. But answering the question of whether the ancient Egyptians could have accomplished this feat does not necessarily mean it was done during the time of Khufu or even during the Old Kingdom.

Construction of the Great Pyramid falls within the technical competence of a long-ago people. But exactly when this ancient civilization did its work is an issue we still need to resolve.

The path toward resolution lies partly in understanding how the ancient Egyptians oriented the Great Pyramid so perfectly to the cardinal directions. To grasp that, we need to look up—to the heavens that fascinated Taylor and Smyth and the distant planets and stars that drew Hoagland, Sitchin, and von Däniken.

AS ABOVE, SO BELOW

TRACKING THE HEAVENS

WHEN THE BUILDERS OF THE GREAT PYRAMID FACED the challenge of orienting the structure to the cardinal directions, they couldn’t simply take a compass bearing. As far as we know, there were no such instruments in those days. But even if the pyramid builders had laid their ancient hands on a compass, it wouldn’t have given them the information they needed. A compass points to magnetic north, which deviates from true north by a significant amount, depending on the bearing-taker’s position on Earth. To use a compass to obtain geographic north (as opposed to magnetic north) in a certain region, you must know how much magnetic north deviates from true north, which means you must know the direction of true north in the first place.

Three fundamental methods of determining true north as accurately as it is incorporated into the Great Pyramid were most likely available to these long-ago builders. One approach, which has a number of possible variations and has long been used in India, focuses on shadows cast by the sun at midday, most accurately near the winter solstice. The other two methods make use of the movement of the stars across the heavens. The first involves sighting a single star against an artificial horizon, such as a perfectly level wall, as it rises and sets, then dividing the arc between them. The second is based on bisecting the extreme uppermost (highest) and lowermost positions of a circumpolar star, one that turns in a small circle about the north celestial pole. Exactly between these two extremes will lie the north celestial pole—or, to find the direction of geographical north on Earth, one can sight on the highest or lowest culmination of the star itself.

Not long before the turn of the nineteenth century, a British astronomer made a good argument for the circumpolar star method. His analysis underscores the fact that the Descending Passage points to a star near the celestial north pole, and in asking when—that is, at what period or periods—this occurred, he takes us back to the question of just how old the Great Pyramid really is.

English astronomer and science popularizer Richard A. Proctor (1837-1888), like many scientists of the Victorian era, began his career as a well-read amateur. One of the writers Proctor delved into was Proclus (A.D. 411?-485), a Neoplatonic philosopher, mathematician, and astronomer. Proclus reported in his commentary on Plato’s
Timaeus
—one of the two Platonic dialogues that mention Atlantis, by the way—that the Great Pyramid had been used as an astronomical observatory before it was completed. Proctor realized the idea made inherently good sense. If the pyramid had been built course by course the way Peter Hodges proposes, the raised square structure would have made an excellent platform for observing movements in the heavens. To make those observations precise and replicable, ancient astronomers needed a baseline. That’s where true north came in.

From the point of view of an earthbound observer who knows nothing of the Big Bang, an expanding universe, or the awesome immensity of in terstellar distances, the night sky looks like a great vault, a rotating sphere in which we find ourselves at the very center. Stars, like the sun, rise in the east and set in the west. The eastern and western horizons provide the outer boundaries of their observable movements. The meridian line, which stretches between the north and south celestial poles, marks the exact center between the two horizons and divides the dome of the sky into two halves. Since a time in antiquity that probably lies far beyond the building of the Great Pyramid, astronomers have made the north pole of the earth and the north pole of the sky one and the same in direction. Determining true north allowed an ancient astronomer—or a modern one, for that matter—to trace the meridian across the heavens and record when the stars and planets crossed it in their transit across the sky.

Locating the north celestial pole is easy enough in theory. It is the point around which the stars seem to turn in their transit from east to west. The closer to the pole one looks, the smaller the circle the stars travel around it. In our time, the single star Polaris nearly occupies this point, and appears to be stationary. But, for reasons of celestial mechanics we will discuss later in this chapter, stars move on and off the celestial north pole. At the time of the Old Kingdom’s Fourth Dynasty, no single star occupied the sky’s north pole. Rather, a small number of circumpolar stars circled round the pole, neither rising from the horizon nor setting below it. The Egyptians knew these stars as the Imperishables. Select the Imperishable with the smallest circumpolar circle, determine the easternmost and westernmost (or northernmost and southernmost) points of its turning, then divide the angle between them in half. The result is true north.

It appears likely that this act of measuring and dividing is the substance of a little-understood ancient Egyptian ceremony known as the stretching of the cord. Depictions of the ceremony show the god Thoth holding a shoulder-high pole in one hand and a club in the other and facing the goddess Seshat, who is holding the same kind of pole and club. Between the poles a circle of cord is stretched. Presumably, the poles are sighting rods driven into the ground with the clubs to mark the east-west extremes of a star’s circumpolar circle. An inscription from Edfu, a Nile River town about 70 miles north of Aswan, that accompanies an image depicting the stretching of the cord reads: “I hold the peg. I grasp the handle of the club and grip the measuring cord with Seshat. I turn my eyes to the movement of the stars. . . . I make firm the corners of thy temple.”
¹
Although this depiction and its inscription date from long after the pyramid age, the ceremony’s roots have been traced to the Second Dynasty.

The stretching of the cord allowed the pyramid builders to transfer the meridian of the sky to the earth. A chalk line would blow away, however, and a simple string like the ceremonial cord could be moved. The builders needed something more permanent. This, Proctor realized, was what they were after with the Descending Passage.

The Descending Passage extends from the north-facing entrance of the Great Pyramid through the lower courses of the monument until it enters bedrock, penetrates deeply into the earth itself, and ends in the Subterranean Chamber. As Proctor saw it, the builders began the Descending Passage at ground level, long before the first course of pyramid masonry was laid. The diggers set the line and angle of descent according to the circumpolar star that they had used to determine true north.

“From the middle of the northern side of the intended base [of the pyramid],” Proctor wrote, “they would bore a slant passage tending always from the position of the pole star at its lowest meridional passage, that star at each successive return to that position serving to direct their progress.”
²

Proctor assumed that this star was Alpha Draconis, which, though faint, circled only 3° 43’ from the celestial north pole around 2140 B.C. and earlier around 3440 B.C. At the Great Pyramid’s latitude, the light from Alpha Draconis at the southern extreme of its nightly circle would have struck the earth at an angle of about 26° 16’-26° 17’. Within the accuracy that the less-than-perfectly-smooth Descending Passage can be measured, this is the angle of the tunnel. The deeper the builders dug and the longer their excavation, the more limited the field of vision and the more accurate their orientation on Alpha Draconis. Indeed, this explains the Descending Passage’s consistent angle and straightness. It has been claimed that originally the straightness varied less than ¼ inch, and the roof slope by under
inch, throughout the tunnel’s 350-foot length.
³
Even if these claims are somewhat exaggerated, the passage is carved with remarkable precision. With the Descending Passage dug, the builders could have used simple trigonometry to place the center of the pyramid over the Subterranean Chamber, set the corners of the pyramid’s square, leveled the site, and begun laying the masonry.

Extending the Descending Passage up through the rising masonry ensured that the structure remained oriented correctly as it rose. This technique ended, though, once the Descending Passage exited the pyramid core at the nineteenth course.

The Ascending Passage, Proctor argued, extended the usefulness of the Descending Passage’s orientation to the celestial north pole. The Ascending Passage rises at nearly the same angle at the Descending: just over 26°. The pyramid builders maintained this angle by following the light of Alpha Draconis in a reflecting pool formed at the junction of the Ascending and Descending passages, according to Proctor. They plugged the Descending Passage, then filled the area above the plug with water. By following the reflection of Alpha Draconis in the pooled water, the builders were able to head south with the same accuracy with which they had earlier gone north.

The Ascending Passage ends in the Grand Gallery, which Proctor saw as the core and genius of the Great Pyramid’s astronomical usefulness. From the point of view of a watcher of the heavens, before its southern end was enclosed, the Grand Gallery was a huge, graduated, vertical slot exactly bisected by the celestial meridian. Looking up along and through the Grand Gallery at the open end, observers could watch the constellations of the zodiac pass through the sky in their nightly east-to-west journeys. The most important measure in such observations is the exact moment when the object being observed crosses the celestial meridian. A Grand Gallery observer could note the time when the star first appeared—which could have been measured with a device as basic as an hourglass or swinging pendulum, with an attendant perhaps chanting out times by the second—then note when it disappeared, divide the time of passage in half, and know precisely when the star crossed the celestial meridian. Do this often enough, for enough stars, and the result is an accurate map of the zodiac and surrounding stars made well before the days of telescopes and fancy mechanical chronographs.