Precession of the Equinoxes Before Hipparchus?

The following paragraphs are from the May 2020 e-update to Before Orion: Finding the Face of the Hero (2017). This section compares the earliest constellations in ancient Greece and Mesopotamia and those found in Paleolithic cave art to hypothesize how Hipparchus may have inherited knowledge for his precession of the equinoxes hypothesis. More on ancient and Paleolithic archaeoastronomy.

By Bernie Taylor | Bernie’s Blog

Social: Twitter, Facebook, YouTube and Academia

Published May 13, 2020

Rediscovering Constellations (from Chapter 16 – Listening to Ogotemmêli)

There is no historical basis to gauge a culture’s body of knowledge by the maxim “if we can’t see (or understand) it today, then no one has seen (or understood) it in the past.” We have found that the observation of specific pictorial characters in constellations have come, gone and come again throughout time. We appear to have lost those constellations and the knowledge held in them represented by the land snail, owl and mongoose while re-finding the bottlenose dolphin and humpback whale depicting roundtrip marine travel in Pisces and recognizing the hero on that same journey emerges in the constellations Hercules, Perseus and Orion.

What were the links in this chain of knowledge from deep in time? Many of Ptolemy’s constellations in his Almagest from around 150 CE that this author has shown to be synchronous with Paleolithic cave pictorial constellations were inherited from the writings of Hipparchus who lived two hundred years before his time and whose star catalog does not survive. Known sources for Hipparchus include the Greek poet Aratus (315 – 240 BCE) and the lost works of the Greek mathematician and astronomer Eudoxus of Cnidus (390 – 337 BCE).

The documented constellations were passed down to us via poems by Aratus and in Ptolemy’s Almagest. The constellations from Aratus do not define the individual stars. Rather, they only provide the relational positions of the pictorial constellations to each other. Eudoxus via Aratus is our closest documented connection to some Paleolithic constellations. Aratus, for example, wrote about the Dragon (constellation Draco) that is representative of the massive crocodile in the image below from the Gallery of Discs.

Some other characters in the Greek constellations of Eudoxus can be found on the Gallery of Discs and set into a pair of tablets referred to as “MUL.APIN” in the ancient Mesopotamian inventory from approximately 1100 BCE. The overlapping pictorial animal being constellation characters between the three cultures include the Lion Leo and Eagle Aquila. Aquila has no resemblance to a bird of any kind and Leo doesn’t obviously look like a lion. Observers have pictured Leo in both horizontal directions. These felid and raptor constellations are sourced from the El Castillo Cave if not earlier in time. Yet, the Paleolithic cave art link to the ancient Greeks is not entirely clear. Eudoxus had not traveled to the Iberian Peninsula to view the cave paintings or to any possible western North African source. Italy was the furthest western point of his journeys. He did have a long relationship with astronomer-priests in Egypt, as scribed by the Greek philosopher Plutarch. Their oral body of knowledge is now lost. Was this his Paleolithic astronomy connection?

Orion, the Great Bear, Sirius as a dog and little more stars are mentioned in the works of Homer and Hesiod from the 8^th century BCE. This is the current known depth of Greek astronomy until the 4^th century revelations from Eudoxus. Other mythical characters, such as Pegasus as told by Hesiod and Hercules by Homer, are found later among the Greek constellations but we have no evidence that these earlier writers were referring to constellations. Ancient Mesopotamian astronomy appears to have entered Greek society at the time of Eudoxus as twenty of his constellations are direct copies from this source and the Babylonian zodiac system arrived there during the same period.

The explicit differences in the Paleolithic constellations that Eudoxus appears to have heard about on his travels and those that Hipparchus observed in his own night sky may have initially suggested the astronomical phenomenon of precession to the latter. Those differences between the two could have been 32,000 years apart with constellations in seasons that would have been obviously out of place to even the novice sky watcher. The clever Hipparchus could have followed this general observation with a study of the individual stars against the equinox in his own time and records from Eudoxus to come up with his monumental “precession of the equinoxes” hypothesis, ushering in what we consider to be the shift from cosmogony to modern astronomy.

Precession can be visually seen over distant millennia in this International Union of Prehistoric and Protohistoric Sciences (UISPP) 2023 World Congress (#UISPP2023) conference presentation “The Archaeometry of Space.” More about archaeoastronomy and cultural astronomy.

We have no evidence that the predecessors of Eudoxus or his contemporaries, including the Egyptian astronomer-priests or Plato as some suggest, had a more accurate measurement of precession than the 1 degree per century estimated by Hipparchus (modern estimate is 1 degree every 72 years). The evidence points to the works of Eudoxus being studied by Hipparchus who built on his foundation of knowledge. The proposal that ancient people before Hipparchus could calculate precession was most notably and elegantly, albeit without evidence, put forth by MIT History of Science Professor Giorgio de Santillana (1902-1974) and Professor of the History of Science at Frankfurt University Hertha von Dechend (1915-2001) in their 1969 book Hamlet’s Mill.

That prehistoric and ancient people found meaning in their night sky and we can today scroll back the movements of stars over thousands of years through our computer software with space age formulas and determine their dates against the archeological record does not support the notion that earlier stargazers could count back into their distant past through astronomical concepts. All of the cave panels dated with astronomy by this author were in the Paleolithic artists’ present and have dates collaborated by physical archeological evidence. We have rediscovered constellations and their origins. We have also re-found more astronomical knowledge that we ever could have imagined. A more precise calculation for the precession of the equinoxes is not on this list.

Bernie Taylor is the author of Before Orion: Finding the Face of the Hero (2017).

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