Sun Stand Thou Still upon Gibeon

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Galileo had imagined a productive existence in his home city - with no teaching, and circumstances easy enough to preclude the need to manufacture instruments or rent out rooms to make ends meet. He had plans for several books, and of course he would continue his observations with the telescope.

He also continued to work on his Copernican ideas. Prince Cesi proved himself a perceptive correspondent, well versed in Kepler's new ideas. In a letter from the summer of 1612 he discusses if any of the heavenly bodies might move round the Earth or the Sun without these necessarily being the exact centre of the orbits. He adds: "... and perhaps everything moves in this way, if the planets' orbits are elliptical, as Kepler has it."

But Galileo did not manage to accomplish everything he wanted. He was often ill, with severe bouts of fever every year or second year. His symptoms sound rather like an hereditary, periodic fever ("Mediterranean fever"), which also causes joint pains resembling rheumatism, something Galileo was very plagued by. The type of rheumatism he suffered from aside, it was not helped by his fondness for wine, which raises the uric acid levels in the blood.

He was also responsible for two young daughters. They were quite unalike. Virginia, the elder, was extrovert and lively, intelligent and - to judge from her later letters - "daddy's girl". Her sister Livia on the other hand, displayed a tendency to melancholy - it was likely she had closer ties to her mother and missed her more.

Galileo had planned similar futures for both of them - he wished to put them into a convent as soon as possible. Respectable marriages were out of the question, as they had been born "out of wedlock". He attempted to mobilise his old benefactor, Cardinal del Monte in Rome, to try to get a dispensation from the rule that nuns must be at least sixteen before taking their conventual vows, but it was no good. In the meantime, in 1613, he boarded them at the convent of San Matteo at Arcetri just outside Florence when they were thirteen and twelve years old respectively. They would live there until they could become nuns.

But also the controversies surrounding his person and his ideas began to take up a lot of his time and energy. In December 1611, Cigoli wrote from Rome:

"I have heard (...) that a gathering of ill-disposed men who are jealous of your talents and your fame, met at the house of the Archbishop [of Florence] and put their heads together..."

He also hints that there are supposed to be plans to ask a priest to declare from the pulpit that Galileo "says extravagant things"29.

Philosophers who whittled ivory splinters to defend their Aristotelian positions were one thing. Priests and archbishops, quite another.

But he did manage to do a little astronomical observation during this period. A small, almost forgotten sighting shows how Galileo with his practical sense had developed into a phenomenally skilful practitioner with the telescope in the space of a couple of years. He could genuinely, and quite literally, congratulate himself on the "lynx-like vision" Prince Cesi believed all the members of his academy ought to possess.

Around New Year 1613, he glimpsed with his still primitive telescope an unknown, dimly glowing body in the vicinity of Jupiter. He noted the find, but the object vanished after a few days, and he did not follow it up. Everything points to the fact that Galileo had caught a glimpse of the as yet unknown planet Neptune, which was not discovered and described until 1846, more than two hundred years later.

Of more immediate importance was another heavenly body. Pointing a telescope directly at the Sun was not particularly wise. But Galileo learnt to project the light from the Sun, through the telescope and on to a sheet of paper. There he could study the Sun's disc minutely. The most striking things were the dark, mobile areas that appeared on it. He called them macchie solari - "sunspots".

Pretty quickly Galileo discovered that these sunspots gave two further arguments against traditional cosmology. In the first place it was clear that the Sun was no more perfect or immutable than the Moon. Secondly, the movement of the sunspots strongly suggested that the Sun rotated on its own axis - in just the same way as Copernicus' opponents said it was impossible for the Earth to do.

So, still no proof, but more and more circumstantial evidence.

Germany possessed an able Jesuit astronomer by the name of Father Christopher Scheiner, who was also interested in sunspots. With their well developed international web of contacts, the Jesuits had got hold of good telescopes, and Scheiner was a fine observer. He now wrote a short account in which he began a discussion with Galileo about sunspots. One of his assertions was that he had seen the phenomenon before the Italian.

But Galileo regarded telescopic observations as his own private domain. His reply to Scheiner - or Apelles, as Scheiner had called himself - was published by the Accademia dei Lincei under the title Letters on Sunspots with a preface that could be read as patronising.

Old Father Clavius of the Collegio Romano died in 1612, and his successors in Rome were not, perhaps, on quite such good terms with Galileo. Although their discussions were couched in the politest terms and expressed mutual respect, a certain reserve began to insinuate itself between the influential Jesuits and Prince Cesi's Academy of the Lynxes. In reality Cesi did nothing to lessen the clash, on the contrary, he regarded his academy as an alternative to the religiously dominated scientific institutions. In fact he had expressly enacted that monks and priests were barred from membership.

This Father Christopher Scheiner would prove to be a man with a very long memory, and he was just as touchy as Galileo himself. But for the time beinghe was polite and reserved, as befitted a Jesuit and a scientist. He replied to Galileo from a more principled starting point. Scheiner wrote (using the name of a pupil) a short book with a long title, Mathematical Discourses on Astronomical Controversies and New Discoveries, in which he argued against Copernicus both from the mathematical and biblical standpoints. He sent the pamphlet to Galileo and evidently hoped for a cultivated discussion between scientists who disagreed purely on professional matters.

Discourse on floating bodies also caused controversy. No less than four books were published that set themselves against Galileo's ideas. One of them was written by the indefatigable Ludovico delle Colombe, who by then had begun to call himself an "anti-Galilean". These opponents were of such humble social status (and scientific status for that matter) that it would have been unseemly for the Grand Duke's mathematician to answer them. According to the custom of the times, Galileo let his best student from Padua, Father Benedetto Castelli, who hadbecome Professor of Mathematics at Pisa, do the answering. This humiliation did not make "the league of doves", as the group eventually became known, any the less intractable.

An odd episode occurred in November 1612, which at first made Galileo furious, but which he subsequently joked about. An elderly Dominican priest in Florence, named Lorini, said during a discussion that as far as he could make out, maintaining that the Earth moved was contrary to Holy Scripture. When Galileo wrote and demanded an explanation, the Dominican replied, apparently defensively, that his remark had been made off the cuff, that he did not have the slightest knowledge of astronomy, or at least not of that "Ipernicus or whatever his name is".

Galileo laughed at the naive priest - triumphantly and far, far too soon. For whether this was pure chance or planned - the next cut was aimed quite differently.

A year later Professor Castelli was lunching with the Grand Duke, who was then staying at his palace in Pisa. The talk centred around Galileo, the telescope and astronomy in general, and another professor who was present said that, for his own part, he was definitely of the opinion that the theory that the Earth moved, was contrary to the teaching of the Bible.

Also present at the lunch was a devout and earnest woman who held the Bible's word in deepest respect: Dowager Grand Duchess Christina, Cosimo's influential mother. Even though Castelli made light of the episode and believed that he had stopped his colleague's mouth, Galileo was worried.

Key to the discussion around the Grand Duke's lunch table was an Old Testament passage from the Book of Joshua, chapter 10, verses 12-13. It deals with a settling of scores between the Israelites and one of their warlike neighbouring tribes, in this instance the Amorites. The Lord waded in with a terrible hailstorm ("... they were more which died with hailstones than they whom the children of Israel slew with the sword"). But Israel's general, Joshua, was not content. He needed more time to complete the massacre of the enemy, and so he offered up this prayer: "Sun, stand thou still upon Gibeon; and thou, Moon, in the valley of Ajalon." God hears his prayer (v. 13): "And the sun stood still, and the moon stayed, until the people had avenged themselves upon their enemies. (...) So the sun stood still in the midst of heaven, and hasted not to go down about a whole day."

The next verse underlines the miraculous nature of the event: "And there was no day like that before it or after it (...)."

If the Lord could, by a miracle, make the Sun stand still, the implication had to be that it normally moved. Therefore there was an open conflict between Scripture's unambiguous words and the Copernican theory. To dismantle the entire ingenious Aristotelian-Ptolemaic philosophical edifice would have profound consequences. It would alter enlightened laymen's picture of the world and undermine the prestige of traditional academics. But Galileo knew only too well that those few words in the Book of Joshua had far more weight for many of his opponents. Scriptural interpretation was not an area for private discussion. In the spirit of the Counter-Reformation, everything of this sort was the absolute monopoly of the Church.

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