Sunday, 21 June 2009

Midsummer and Ritual

As Midsummer tends to be associated with solstice rituals, etc, when I was writing my "Midsummer Dreams", I was looking at providing something fictional that would reflect that, but also reflect Carl Sagan, in his wonderfully poetic but scientific appreciation of the Cosmos, in the television series of the same name. As he said:

We humans long to be connected with our origins so we create rituals. Science is another way to experience this longing. It also connects us with our origins, and it too has its rituals and its commandments. Its only sacred truth is that there are no sacred truths. All assumptions must be critically examined. Arguments from authority are worthless. Whatever is inconsistent with the facts -- no matter how fond of it we are -- must be discarded or revised. Science is not perfect. It is often misused. It is only a tool, but it is the best tool we have -- self-correcting, ever changing, applicable to everything. With this tool we vanquish the impossible; with the methods of science we have begun to explore the cosmos.(1)

With this in mind, I decided to look at a much more cosmic outlook. So much of mythology and ritual tends to be very dependent on local seasons. For instance, our longest day is today, but on the equator - although the time of sunrise and sunset alter - the length of daylight is always the same.

Now in fact the length of daylight has not always been the same because of the drag effect of the moon, and I remember doing calculations on this years ago in A-Level physics. This is the physics of daylight hours:

The fish of the Devonian Period experienced rather short days. We know that the Devonian year had 400 days, making each day only 22 hours long.(72 kb) This just goes to show that nothing is constant on Earth, not even the length of a day! Just as continents move and change direction, the speed at which our planet rotates also changes over time. How is this possible? It is really the fault of the Moon, our celestial companion. Since it formed 4.2 billion years ago (4.2 Ga), the Moon has driven the tides on our planet. The Moon's gravitational pull attracts great masses of water toward it while in orbit around us. As the Earth turns eastward, the tides move westward, and this phenomenon imperceptibly slows the rotation of our planet by 0.0016 seconds per century! (2)

What is extraordinary about this is that there is what we might term a "cross bearing", an independent means of verifying this, which shows that out physics tallies with the biological evidence:

One line of evidence comes from corals. Corals, both living and fossilized, are animals that live inside little cups of calcium carbonate (calcite; CaCo3) that they themselves secrete. The coral "skeleton" grows because the animals deposit calcite every day they are alive. The activity temporarily stops at night because the animals live symbiotically with single-celled algae that need light to function. The daily layers are visible under a microscope, making it possible to count days, somewhat like counting tree rings to determine the passage of years.  Species that live in temperate waters are subjected to seasonal variations in temperature, so winter growth is slower and the marks farther apart. Years are therefore easily distinguished among the series of growth lines. A modern coral would show us years consisting of 365 lines. Coral fossils living 400 million years ago (400 Ma) in the Early Devonian display years of 400 lines, and thus 400 days, proving that the Earth did indeed turn faster at that time.(3)

I wanted to write something for Midsummer that reflected this vast change in the day since ancient times, what the paleontologists term "deep time", and then, for completeness, I went back imaginatively to the start of the earth, close to its initial formation as a planet.

Sometimes, I think it is good to get a cosmic perspective, and I was listening to a poem only the other day which spoke of "a hundred thousand years" as if that was a vast period of time; in fact, it puts us back in the Paleolithic period, on the earth's history in time as one hour, barely the last minute. How provincial we are, and how localised in out perceptions.

I didn't look forward to the slowing down of the earth, because that has already been done, and far better than me, by H.G. Well's in his Time Machine. Wells was as aware of the slowing down of the earth by tidal drag, and the eventual extinction of all life, or certainly of human beings:

So I travelled, stopping ever and again, in great strides of a thousand years or more, drawn on by the mystery of the earth's fate, watching with a strange fascination the sun grow larger and duller in the westward sky, and the life of the old earth ebb away. At last, more than thirty million years hence, the huge red-hot dome of the sun had come to obscure nearly a tenth part of the darkling heavens. Then I stopped once more, for the crawling multitude of crabs had disappeared, and the red beach, save for its livid green liverworts and lichens, seemed lifeless. And now it was flecked with white. A bitter cold assailed me. Rare white flakes ever and again came eddying down. To the north-eastward, the glare of snow lay under the starlight of the sable sky and I could see an undulating crest of hillocks pinkish white. There were fringes of ice along the sea margin, with drifting masses further out; but the main expanse of that salt ocean, all bloody under the eternal sunset, was still unfrozen.

The darkness grew apace; a cold wind began to blow in freshening gusts from the east, and the showering white flakes in the air increased in number. From the edge of the sea came a ripple and whisper. Beyond these lifeless sounds the world was silent. Silent? It would be hard to convey the stillness of it. All the sounds of man, the bleating of sheep, the cries of birds, the hum of insects, the stir that makes the background of our lives--all that was over. As the darkness thickened, the eddying flakes grew more abundant, dancing before my eyes; and the cold of the air more intense. At last, one by one, swiftly, one after the other, the white peaks of the distant hills vanished into blackness. The breeze rose to a moaning wind. I saw the black central shadow of the eclipse sweeping towards me. In another moment the pale stars alone were visible. All else was rayless obscurity. The sky was absolutely black.(4)

(1) Cosmos, Who speaks for Earth, Carl Sagan

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