A theological blog 28 -ii -19. Milankovich cycles
Milutin Milanovich was an engineer employed by the Austro-Hungarian Empire in the early twentieth century. A Serb, he was interned in Budapest during the First World War and spent much of his time in the library of the Hungarian Institute of Sciences, pondering on the puzzle of what caused the ice ages. His discovery that the earth travels round the sun in three elegantly precise interlocking cycles is hailed today as one of the greatest achievements of climate science. The longest of these cycles concerns the changing shapes of the ellipses the earth follows in its annual journeys round the sun and lasts for 100,000 years. When the orbits are strongly elliptical the earth is both nearer and farther away from the sun and there are heightened differences, and therefore seasonal temperatures, in the amount of radiation falling on the earth. At the moment, we are not in a strongly elliptical part of the cycle and the differences between January and July are relatively small. The second cycle concerns the earth’s changing tilt on its axis and lasts for 42,000 years. The third cycle dictates the wobble of the axis of the earth. When the axis is pointing towards the Pole Star the seasons are mild in their intensity. At other times, these alternating wobbles produce bitterly cold winters and scorching hot summers.
The extraordinary precisions and the interlocking accuracies and the exact repetitions, the unbroken integrity, of this vast cosmic architecture is intellectually truly mind-blowing. But I find the Milankovich cycles engage my emotions as well as my intellect, so awesome are they, and, indeed, I note with some amazement that I am taking the same pleasure in contemplating them that I feel when ravished by music. The harmony of it all, the interweaving polyphonic conceptions, the repetitions, almost as if the current movements of these cycles were a gathered enrichment of all that has gone before in sonata form, the pulsing rhythms, each day a different note, each season a new passage in a different key, each year a new movement, all gathered into an over-arching integrated structure. But perhaps the analogy with music is not surprising, for the melodies we hear in music are only the outer expressions of profounder inner conceptions of harmonies and rhythms, the more exquisitely heard by an inner ear. Beethoven, after all, wrote his greatest music when he could not hear a single note. Rhythms and chords and concordances are found in other arenas than those that can be expressed in sound, hence the music of the spheres. And music is always more than a registering of arpeggios and keys, more even than hearing the songs of angels and feeding on the food of love. It is always also a dialogue with the composer, an encounter of subjectivities, a personal meeting, the devotion of a disciple to a master, my educative enrichment by you. My brain is stunned but my heart laid open by the great wonder of Milankovich cycles. What intellect can have conceived so exquisitely a precise and harmonious a vast universal symphony? I find myself invited, almost driven, into prayer.