Week 2: Interpretation Essay

My main interest throughout this week has been the zodiac, and I would contend that the Babylonians who gave us the zodiac were surely scientists. My previous understanding of the zodiac was entirely non-scientific, but now — especially after having struggled through the pages in Michael Crowe's Theories of the World devoted to the astronomy that led to the zodiac — I have to confess both my ignorance of how the zodiac really works (but I did try to understand!) and my absolute amazement that the ancient Babylonians were able to conceive of extra-terrestrial space in such a complex way. As I understand it, the Babylonian astronomers around the year 1000 BCE had already divided the ecliptic up into twelve zones to create something like a celestial map. I am very glad to say that I now understand the ecliptic, even if the zodiac itself is still beyond me!

For people who did not get a chance to read those pages in Crowe, he walks us through a geocentric understanding of the motion of the sun and the moon, starting with the notion of a starry vault which rotates around the earth on the earth's polar axis, so that for us Polaris is a fixed star, while the other stars rise and set. But then to understand the sun's path we need to conceive of the ecliptic, and thank goodness Crowe told us to think of an ant walking slowly down the side of a spinning basketball. So far, so good. I understand the ecliptic now, and it is very helpful in my quest to really understand how sundials work! Plus now I understand the solstices and the equinoxes, and I finally understand why it is so darn cold in the winter.

But then: oh no, here comes the zodiac, which is this astronomical space extending on either side of the ecliptic such that the sun, moon and the planets move within this space, allowing their movements to be charted and predicted (science!). Crowe tells us to imagine the zodiac like a belt that is unwrapped and laid out flat, and then we can chart the moon's path through the houses of the zodiac. At that point, my brain explodes. It's a very pretty chart, but I no longer have the ant on the basketball to help me. I am lost! Crowe's subsequent charts using the zodiac, like the chart showing the difference between the draconic and sidereal periods of the moon, completely baffled me.

But the Babylonians were not baffled. Not only did they understand the zodiac... they discovered it! Invented it! Whatever you want to call it, they did it, and I would declare it a scientific event.

It is also a mysterious event because of the many gaps in our historical reconstruction. The origins of the signs of the zodiac, for example, which are still used today, are lost in antiquity. I found a fascinating article — "The Zodiac and Early Astronomy" by S. H. Dewdney (Journal of the Royal Astronomical Society of Canada, 1931) — which provides an overview of the different theories as to the possible origins of those familiar zodiacal signs.

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So, the signs are familiar while the scientific concepts are formidable, and the origins of both are lost in time. Over the past thousands of years, I suspect there have been many people like myself who "know" the zodiac (that is, we recognize the signs and find meaning in them) but without understanding the science behind it. No surprise: the science is hard! But the signs themselves are beautiful and suggestive, and they have been part of diverse art traditions for many centuries. So, even though I am defending Babylonian science, I will finish with some art, sharing an item I found in the Wikimedia Commons area devoted to the zodiac and its signs.

This lovely image shows the labors of the seasons, along with the signs of the zodiac over the course of a year. Isn't it gorgeous? It is dated to around the year 1400 and comes from the Berlin State Library. I like the way it unites the everyday experiences of people at work with the astronomical dimension of our world in the skies above us. I think that if the ancient Babylonians could have seen this work of art, they would have appreciated it too!

(Faltkalender, circa 1400)

(I chose this personal style of essay because I am still hoping against hope that Janux will be a place for people to really get to know each other, person to person, in order to share in a social learning experience.)