Precession of the Equinoxes and the Golden Fleece

Jason and the Argonauts Give Newton a Lift

Imaginary or not, Jason and the Argonauts yet find their story writ large in the night sky. The constellation Argo, rising just above the horizon, commemorates the swift 50-oared longboat that carried Jason and his crew of 50 heroes around the ancient world in search of the golden fleece. Lyra, or the lyre, higher in the sky than Argo, honors the Argonaut/demigod Orpheus who, perched on the stern of the boat, played his enchanted lyre and charmed the rowing warriors into redoubling their efforts and the fish of the sea into following behind in an enthralled and gamboling troupe.

There is the constellation Centaurus, or the Centaur, which immortalizes the centaur Chiron whose human portion ended at the waist and became the hindquarters of a horse. Chiron was as famed as an astronomer as he was as a physician (or so some claimed); he mentored several of the Argonauts and designed the celestial sphere that, inscribed with the constellations, helped guide the Argonauts on their perilous journey. And there are numerous other stars and star-groups in the sky whose names sparkle with hints of the Argonautic legend.

The story of Jason and the quest for the golden fleece was of intense interest to Sir Isaac Newton (1642–1747), the man who discovered the law of gravitation and the three laws of motion and unlocked the secrets of light while carrying out exhaustive researches in alchemy, prophecy, and church history. It’s surprising that this austere and haughty genius who hated poetry and fled, halfway through, from the one performance of an opera he ever attended, should be caught up in the enchantment of the Argonautic legend. Yet caught up he was, in particular by Chiron, but not least because all the dramatis personae of the Argonautic expedition had been emblazoned on the night sky.

This fascination stemmed from the monumental work on the chronology of the world from the Creation to Alexander the Great that Newton labored over from his late fifties until the weeks before he died. Published posthumously in 1728, The Chronology of Ancient Kingdoms Amended uses immense scholarship, a multitude of strategies, and in particular two highly innovative tools, to shave five hundred years off the traditional age of the ancient world.

Newton’s first innovative tool was the law of regnal lengths. He demonstrated that kings and queens reigned only 18–20 years on average. The earliest records of mideast nations had been clogged with duplicated and fictional rulers, said Newton, so much so that the Babylonian chronicler Berossus claimed Babylonian history went back almost half-a-million years (two hundred thousand years before the appearance of Homo Sapiens). Researching prodigiously, Newton slashed these ancient dynasties left and right, conflating two and even three rulers into one and eliminating other rulers and the occasional whole dynasty. (See “The Politics of Time” in Atlantis Rising #96).

Many critics objected to Newton’s seeming cavalier use of the law of regnal lengths, which eliminated five centuries from recorded history. They were equally upset with the second innovative tool the great man used. Still, they couldn’t help but admire Newton’s boldness in employing this particular tool, a component of the new science of astronomical chronology: Newton had managed to harness the phenomenon of the precession of the equinoxes to voyage back in time and shore up all his conclusions.

In Newton’s time it wasn’t uncommon for savants to use celestial phenomena to date a historical event (though the information they sought sometimes seems whimsical to us today). The Polish astronomer Hevelius worked out the position of the sun over Eden on the day of Creation. The uncommonly brilliant Edmund Halley, after whom the comet is named, used all his skills to find out precisely when and where Julius Caesar made landfall in Britain. A long lost, second century Greek text had been quoted in a later document as stating that a solar eclipse along with an earthquake took place in Bythnia (now northwest Asian Turkey) in the fourth year of the 202nd Olympiad. It was Isaac Newton who, seizing upon this data as a reference to the darkness that accompanied Christ’s crucifixion, used it to deduce the year Jesus died: 34 BCE (Newton wasn’t fazed when his colleagues pointed out that a solar eclipse lasts no more than six minutes, while the darkness over Golgotha lasted nearly three hours.)

Newton eclipsed all of these achievements, however, when he hitched his researches to the precession of the equinoxes to journey back and find an anchor date in the ancient world around which he could arrange events in the way that he thought fit.

But what exactly is the precession of the equinoxes?

The earth’s poles have a very slow, backward-sliding, east-to-west motion. As our planet spins on its axis, they wobble very slightly, such that their position every day doesn’t correspond exactly with the same point in the heavens. This very slow motion, called the precession of the equinoxes, inscribes a complete circle over a period of 25,900 years; we perceive it as a minuscule slippage backwards of the fixed stars vis-à-vis the rising and setting of the sun.

This tiny, continuous change of place of the constellations is distinct enough that we can say that each night sky has, so to speak, its own unique fingerprint. This forward motion of the wobbling poles, which even over a year is hard to discern, becomes apparent in time; over the seventy-two-year lifespan of a man or woman the constellations as a single block move one degree through the sky. (One degree is one 360th of the circumference of the heavens.) Thus, after seventy-two years, the “colure”—one of the two great circles that include the poles and the equinox or the poles and the solstice—which passed through a particular fixed star now passes through another fixed star.

Since the precession of the equinoxes completes a full circle every 25,900 years (a figure established by Newton), the sun finds itself in a different sign of the twelve signs of the zodiac every 2,156 years. When the Greek astronomer Hipparchus lived (c. 190 BCE to c. 120 BCE), the sun rose and set in the sign of the Ram (Aries); over the past two thousand years it has been passing through the sign of Pisces.

To make use of the precession, Newton needed to find an ancient description of the night sky—a star map, a celestial sphere, a verbal portrait. Then he had to calculate the position of the sun at equinoctial times from that particular fingerprint of the heavens. Next he had to translate the ancient data he’d obtained into modern-day astronomical terminology. Then he would have his date.

All this was so difficult that only an Isaac Newton could have attempted it. Very few descriptions of the night sky had survived from antiquity. The observational devices and methods used by the ancients to map the heavens were largely unknown; it would take a mountain of ingenuity to decode the descriptions and translate them into contemporary terms. Finally, to be usable, the data you had teased out of time had to be attached to a specific, previously undated, historical event; only then could it become the reference point that Newton needed.

The great man wasted a lot of time in false starts, like minutely analyzing the description of the rising and setting of Arcturus in the eighth century BCE poet Hesiod’s The Works and Days; this yielded up only burdensome obscurities. Finally Newton focused on an engaging third century BCE document that may have helped him overcome his aversion to poetry, and its prose counterpart, a document that had been preserved, in the first century AD, in one of the greatest works of astronomy ever written.

In 276 BCE, a Greek physician named Aratus published a 1,000-line book of poetry called the Phaenomena (Phenomena). It described the constellations and how to use them to predict the weather. Original and lyrical, the book became a bestseller. Aratus’ poetic descriptions were translated into sky charts that often came to be emblazoned on the concave ceilings of the homes of the rich and famous and sometimes on temple ceilings.

Early in the first century BCE, Cicero translated Aratus’ Phaenomena into Latin. It became a Roman best seller. Leisured matrons took genteel pleasure in working the celestial patterns in gold and silver onto costly wall hangings and coverlets. The poet Ovid re-translated the Phaenomena, as did the popular Roman general Germanicus Caesar. St. Paul is supposed to have quoted Aratus’ verses on Zeus (Acts 17, 28) when he addressed the Athenian crowds at the Areopagus.

Midway in its journey down from Athens to Rome, the Phaenomena had taken a beating. Aratus’ poem was a versification of a now-lost prose counterpart, also called Phaenomena, written by the Greek astronomer Eudoxus (410/408 B.C.E.–355/347 BCE) in 366 BCE. We know about Eudoxus’ treatise because the Greek astronomer Hipparchus (ca. 190 BCE–ca. 120 BCE) summarized it, and Aratus’ poem, in a Commentary in which he took both texts to task for their inaccuracies. Hipparchus had the right to criticize: considered ancient Greece’s greatest astronomer, he founded trigonometry and, it is generally believed, was the first (some except the Babylonians and still others have produced other candidates) to identify the precession of the equinoxes.

Hipparchus’ Commentary is also lost in the mists of time. We know its contents because the Greek astronomer Ptolemy (c. AD 90–AD168) included most of the text in his compendium of astronomical lore later called by the Arabs the Almagest (Greatest Book). This landmark work, which describes in its most elaborated and cogent form the geocentric universe known as the “Ptolemaic,” came to be the standard astronomy textbook of the Mideast and Europe up until the fifteenth century.

It was to Eudoxus’ Commentary, preserved by Hipparchus and then by Ptolemy—and with side glances at Aratus’ versification of Eudoxus’ text—that Newton now turned as he set about riding the precessing equinoxes back in time to determine the correct dates of ancient history. It’s not within the scope of this article to describe the excruciatingly complicated computational maneuvers that he went through to arrive at his conclusions; but he finally decided that the Eudoxus/Aratus description fingerprinted the night sky sometime in the year 939 BCE.

This surprised many. Eudoxus had, after all, lived in the fifth century BCE. Newton pointed out that Eudoxus said he was working with a “primitive sphere,” one that had been passed down to him from previous generations. Not knowing about precession, Eudoxus had no reason to believe that the constellations inscribed on this “primitive” sphere were placed any differently than the constellations in the skies of his own time. He saw no reason to try to date the sphere.

Newton pounced on the elusive, not entirely creditable, legend repeated in a second century AD text by St. Clement of Alexandria, that the constellations were invented by Chiron at the time of the Argonautic expedition and inscribed on a celestial sphere for the use of Jason and his men as they navigated uncharted waters. Therefore, declared Newton, Eudoxus’ “primitive” sphere must have mirrored the night sky in roughly 939 BCE, and this must have been the year of Jason’s quest. The Argonautic expedition was believed to have taken place forty-two years after the death of Solomon and thirty years before the Trojan War. Now Newton had new dates for Solomon’s death and the Trojan War, which were roughly five hundred years before the conventionally accepted dates. He had once again shaved five hundred years off the traditional chronology.

(The glibness with which Newton transformed heroes like Jason, demigods like Orpheus, and mythical figures like Chiron into datable personages in the ancient Mediterranean seems bizarre to us now. We have to remember that he and his contemporaries subscribed to the still respectable doctrine, promulgated by the second century BCE Greek philosopher Euhemerus, that all figures of myth and legend were trailblazing human leaders who had been deified by their grateful descendants.)

Newton had further evidence that Chiron invented the celestial sphere—evidence that explains his fascination for the story of Jason as writ large in the stars. He listed the numerous stars and star-groups that derive their names from the Argonautic expedition. Then he pointed out that this was the last group of historical figures to be commemorated in the stars. The Trojan War took place only thirty years later (Newton claimed), and yet there were no constellations named Helen, or Paris, or Achilles, or Hector, or Briseus, or the like.  This meant that Chiron had finalized the names of the constellations in the year of Jason’s expedition; the centaur had virtually commemorated the Argonauts in advance.

Most of Newton’s critics accepted that Chiron created the first celestial sphere, but they objected to Newton’s new dates on other grounds. And they smelled a rat. It had long been known that Newton—though this hadn’t been the case when he began his Chronology—had an ulterior motive when he revised the dates of antiquity: he was intent on proving that the Jewish people were the first to establish a civilization. To show this, he argued indefatigably throughout the Chronology that many of the ancient non-Jewish kingdoms had been no bigger than English villages for long periods of time and not able to sustain a civilization until less than a thousand years before Christ. Placing Solomon’s death forty-two years before the Argonauts suited him well: Solomon’s reign marked the fine flowering of Jewish civilization, while the Argonautic expedition marked only a first step toward the establishment of Greek civilization. Newton would later argue that ancient civilizations such as Greece and Egypt received their arts and sciences from the Jewish people, and not vice versa; the Jewish state was the first civilized entity.

Newton changed his stance several times vis-à-vis the nature of the Argonautic expedition. At one point he claimed the Argonauts were only pretending to look for the golden fleece, that their quest was a cover story for a huge exercise in international diplomacy. “A message by the flower of Greece could be no other account than state-policy,” Newton stated. At another point he seemed to speak of the expedition as emblematic, almost archetypal—a watershed point through which all embryonic nations passed when they moved from quasi-civilization to the real beginning of civilization. Here Newton seems to agree with those historians of antiquity who thought the story of the Argo might be the memory of the first iron boat, or the first longboat; in fact, historians today believe the first 50-oared longboat appeared in about 700 BCE.

There may be more than meets the eye in Newton’s fascination for Jason and the search for the Golden Fleece. Newton was the greatest alchemist of his time; he tirelessly sought the Philosopher’s Stone that could transmute base metals into gold—and the Philosopher’s Stone was also called the Golden Fleece. It may be that Newton—so brilliantly intuitive that he often arrived at a conclusion without proof and created the proof afterwards—saw depths in this legend he didn’t choose to reveal to us. It must have been meaningful for him that the Argo was partially driven by the magical lyre playing of the Orpheus who knew the music of the spheres. Newton believed the music of the spheres was a prefiguration of the law of gravitation; if he believed the Golden Fleece was somehow an elaboration of that, then that’s a secret that the rest of us will likely never penetrate.

By John Chambers