Transit of Venus (Matins, Pentecost)
30 May 2004 at :00 am
Sermon for Matins, Pentecost, 30 May 2004, St Margarets
by the Reverend Nicholas Sagovsky, Canon Theologian
Is 40:12-23; I Cor 2:6-16
Who has measured the waters in the hollow of his hand
And marked off the heavens with a span
Who has directed the Spirit of the Lord,
Or as his counselor has instructed him?
On Tuesday 8 June, for the first time since 1882, we shall be able to see the transit of Venus. From early morning until approximately midday, a small black dot, clearly visible throughout Europe, will pass across the face of the sun. The transit of Venus will happen once more in 2012 and then not be seen again for over a hundred years.
The first person to observe the transit of Venus was Jeremiah Horrocks, a young man, who had studied at Emmanuel College, Cambridge and was then living, perhaps as curate, in the Lancashire village of Hoole, near Preston. The famous astronomer Kepler had before his death predicted the transit of 1631, but the young Horrocks was the only person to realise that a second transit would follow eight years later, in 1639. He worked this out just weeks before it was due, telling friends to observe on 24 November. His friend and scientific correspondent William Crabtree spent the day poised in Manchester, only to find that (as is still often the case) the cloud barely lifted! When it finally cleared, and he saw the small black sphere on the surface of the sun, he failed to take any measurements. Horrocks, thirty miles to the north, did rather better:
I watched carefully on the 24th from sunrise to nine oclock, and from a little before ten until noon, and at one in the afternoon, being called away in intervals by business of the highest importance ... . But during all this time I saw nothing in the sun except a small and common spot . This evidently had nothing to do with Venus. About fifteen minutes past three in the afternoon, when I was again at liberty to continue my labours, the clouds, as if by divine interposition, were entirely dispersed and I was once more invited to the grateful task of repeating my observations. I then beheld a most agreeable spectacle, the object of my sanguine wishes, a spot of unusual magnitude and of a perfectly circular shape, which had already fully centred upon the suns disc on the left . Not doubting that this was really the shadow of the planet, I applied myself sedulously to observe it.
The observations Horrocks made on that and the following days represented a major step forward in understanding the motion of the planets. His correct prediction of the transit of Venus resoundingly confirmed Keplers general theory of planetary motion (though not Keplers estimate of Venus size) and laid some of the mathematical groundwork for Newtons theory of gravity. It also laid the groundwork for ever more accurate measurements of the distance of the earth from the sun. That moment, half an hour from sundown, when the clouds cleared and the sun demonstrated the black disc that only Horrocks in all the world had predicted, was one of the great moments of the early scientific revolution.
Whether he was a clergyman or not, it is clear that Horrocks, like many of the gifted scientists of the seventeenth century scientific revolution, including Sir Isaac Newton, was a convinced Christian believer. His work was done in part to answer the Psalmists question: When I look at thy heavens, the work of thy fingers, the moon and the stars which thou has established; what is man that thou art mindful of him? (Ps 8:3). The most important contemporary authority on Horrocks, Allan Chapman, writes, What shines through Jeremiahs writings is a sense of awe and praise for the Deity who could make a universe that was so intricate and so beautiful. One also perceives his sense of privilege at being the first human creature to learn of certain things such as the shape of the moons orbit or to see the transit of Venus. ( Jeremiah Horrocks and Much Hoole, 1994, p. 10). As a mathematical astronomer, Horrocks believed himself merely to be tracing the handiwork of the one who had marked off the heavens with a span. In the text we read earlier, Isaiah asked rhetorically whether anyone could compare to God as a cosmic craftsman. Horrocks would have seen his own work as providing further evidence in support of Isaiahs remarkably probing questions.
There was a further step Horrocks took, in which he differentiated himself from his Lutheran intellectual master, Kepler. Keplers astronomy differs from mine as [does] his religion, he wrote. For Horrocks, each planet was naturally averse from the Sun and desirous to rest in his own place because it had a material dulness naturally averse to the Sun without either power or the will to move to the Sun of itself. We would speak of the planets inertia. But then, he goes on, the Sun by its own ray attracts and carries about the unwilling planet, conquering that self-rest that is in it; yet not so far that the planet doth [not] much abate and weaken this force of the Sun . He then moralises, I will confess myself wholly desirous to rest in myself, and wholly averse from God, and therefore justly deserve (as the fixed stars from the Sun) to be blown away from God in infinitum; but that God, by his Sons taking on Him mans nature and [by] the undeserved inspiration of his Spirit, doth quicken this dullness, nay deadness of my nature, yet still, ah me! how doth [my dullness] choke and weaken their operation. ( Philosophicall Exercises, Part 1, para 26)
This passage beautifully illustrates how Horrocks saw behind the laws of planetary motion and the divine plan of salvation the one Spirit of God. He saw the same pattern of divine working in the salvation of recalcitrant human souls through the attractive power of the incarnation of Jesus Christ and the motion of recalcitrant planets drawn on by the attractive power of the sun. In the language of Isaiah, it was the one Spirit of the Lord that inspired both.
Horrocks intuition is still of profound spiritual value today. First, there is his astonishingly vindicated belief in the absolute predictability of planetary motion. He believed that we live in a universe which is predictable because God has built into it such consistency of working that we can model planetary motion mathematically; we can accurately predict cosmic events and accurately measure cosmic distances. The fact that we can do so was not for him a means of showing that we do not need to think in terms of a God (as the later mathematical astronomer Laplace said to Napoleon, I have no need of that hypothesis), still less that human beings are themselves little gods, but that God has done his work with the perfect skill of a unique master craftsman. More than that, for Horrocks, when we reason correctly we are able to enter into the mind of God, not to direct the Spirit of the Lord, nor to instruct him how to do things better, but scientifically to trace the workings of the Spirit of the Lord.
Horrocks was at Cambridge at the same time as the Cambridge Platonists, who spoke of reason as the candle of the Lord. To support this understanding of reason, they frequently quoted the psalm, For with thee is the fountain of life; and in they light shall we see light (Ps 36:9). Our problem with so understanding reason is that the notion of reason has itself radically changed. Like Laplace, we no longer see reason as needing to be inspired in the way that Horrocks did, when he spoke of the undeserved inspiration of [Gods] Spirit which overcame his own moral inertia. It takes a bold theological thinker to advance in the contemporary world the thesis that the pattern of Gods reason, working in all the universe, is to be seen both in the motion of the planets and in the unique, historical events of the cross and resurrection of Jesus Christ, but this is exactly what Horrocks believed, when for half an hour on the 24 November, 1639, he alone in all the world measured the transit of Venus.
Only in the nineteenth century did Horrocks receive some of the recognition he deserved. Just inside the West Door of Westminster Abbey, opposite the imposing monument to Isaac Newton, is a monument to this extraordinary young man of whom Newton himself spoke with admiration. It was erected in 1874, more than two hundred years after his tragically early death in his twenty-second year. When you look at it, you will see quoted, along with the list of his extraordinary astronomical achievements, his own words: Ad majora avocatus, quae ob haec parerga negligi non decuit, which might be translated, To the greater advocate [that is the Holy Spirit] who, in the consideration of these lesser works, should not be overlooked. For Horrocks, the Holy Spirit was given as much to bear witness about the truth of Jesus Christ as to illuminate the workings of the Creator in the heavens. For him, these two dimensions of truth went hand in hand, because it was the one God, Father, Son and Holy Spirit, who was to be recognised in both. As, on Tuesday, we consider only, of course, indirectly, like Horrocks, or through darkened lenses - the transit of Venus across the face of the sun, may the presence and power of the Holy Spirit, who has brought us to predict, see, and reflect on the remarkable works of God, indeed not be overlooked.