The Science of Shakespeare (10 page)

“A NEW AND UNUSUAL STAR”

But the most stunning celestial event—the one that cemented Tycho's passion for astronomy and would end up changing the course of Western thought—came in the autumn of 1572, when the new star exploded into view in the northern sky. His travels behind him, Tycho was living in Scania, where he had built a small observatory on grounds owned by a relative. Tycho first spotted the star on November 11. (A handful of other European observers, it turns out, had seen it a few days earlier.) His excited tone was still in evidence months later, when he set his thoughts to paper:

Amazed, and as if astonished and stupefied, I stood with my eyes fixed intently upon it. When I satisfied myself that no star of that kind had ever shone forth before, I was led to such perplexity by the unbelievability of the thing that I began to doubt my own eyes.

Tycho studied the star's appearance over several weeks; he also compared notes with other observers across Europe. He hurriedly wrote and published a short book describing his account of the event, called
De Nova Stella
(
On the New Star
). (The full title was actually
De nova et nullius aevi memoria prius visa stella
[
Concerning the Star, New and Never Before Seen in the Life or Memory of Anyone
].) His tone was not exactly modest:

I noticed that a new and unusual star, surpassing all the other stars in brilliancy, was shining almost directly above my head. And since I had almost from boyhood known all the stars of the heavens perfectly … it was quite evident to me that there had never before been any star at that place in the sky, even the smallest, to say nothing of a star so conspicuously bright as this.

The new star, appearing out of nowhere, was “the greatest wonder that has ever shown itself in the whole of nature since the beginning of the world.”

Unfortunately, new stars
weren't supposed to happen
. It was an affront to Aristotelian and Ptolemaic cosmology, in which the heavens, by their very nature, were believed to be perfect and unchanging. How could one make sense of the appearance of a new star? One possible resolution was to imagine that it was actually a terrestrial phenomenon; perhaps it was located high in the Earth's atmosphere. (Think of the momentary difficulty one has today in distinguishing a star from an airplane.) If it were shown to be “sublunar,” all would be well in Aristotle's world. Yet if the new star were a “local” phenomenon, it would display parallax—in this case, meaning that it would be seen at slightly different locations (relative to the background stars) by observers at different locations on the Earth—or, indeed, by a single observer watching over an interval of several hours, because the Earth, as it rotates, would carry the observer over a distance of several thousand miles.
*
The moon, which traditionally denoted the boundary between the corruptible terrestrial region and the perfect realm of the stars, was known to display a parallax of roughly one degree. But Tycho's new star showed no discernible parallax. In addition, it seemed to stay in the same location in the sky, relative to the other stars (displaying no “proper motion,” as an astronomer would put it). “I conclude,” Tycho wrote, “that this star is not some kind of comet or fiery meteor … but that it is a star shining in the firmament itself—one that has never previously been seen before our time, in any age since the beginning of the world.”

Fig. 3.1
Danish astronomer Tycho Brahe was among the first to see the “new star” of 1572 (depicted here above the “W” of Cassiopeia, and identified in Latin as “Nova Stella”). The star's appearance challenged the Aristotelian picture of the universe, in which the heavens were imagined to be perfect and unchanging.
The Bridgeman Art Library, London

Tycho was anxious to know what observers elsewhere in Europe thought about this strange and wonderful object. Thousands of people must have seen the new star, including dozens of professional astronomers, astrologers, and mathematicians. Many of them, like Tycho, rushed to get their observations into print. Among them was an English astronomer named Thomas Digges, one of the most important English thinkers of his day.

LEONARD AND THOMAS DIGGES

History has a funny way of allotting celebrity. Only the smallest handful of physicists and astronomers have come down to us as household names: Copernicus, Galileo, Newton, Einstein. From the next tier we have names like Tycho Brahe and Johannes Kepler—well known to those who have studied astronomy or taken a history of science course, but largely unknown to the general public. And then we have those who ought to be as well known, but, due to the vagaries of history, haven't received their due. It is from this group that we find Thomas Digges (ca. 1546–1595). Digges was a military engineer and a member of Parliament—but that is not why he is remembered. Instead, we know him as one of the first English Copernicans, a man who gave us a new vision of the cosmos.

Science seems to have run in the Digges family. Thomas's father, Leonard, was a distinguished mathematician who had studied at Oxford, where he developed an interest in problems of surveying—he invented the theodolite, for measuring angles—and in matters of defense. In 1555 he published an almanac,
A Prognostication of Right Good Effect
, which contained weather predictions as well as instructions for using various mathematical instruments for astronomy and navigation. It also included an outline of Ptolemy's description of the cosmos. Another of his books, on surveying, remained in use for the next 150 years, going through at least twenty editions. Striving to speak plainly on all manner of practical problems in surveying, he complained of the many books on geometry “locked up in strange tongues.” He instructed his readers to go through the text once, and then a second time “with more judgement, and at the third reading wittily to practise” the various methods described, all in the aim of “profitable labour.” Incidentally, all of these accomplishments might never have come to pass had history taken a slightly different turn: In 1553, Leonard got caught up in what would become known as Wyatt's Rebellion, a plot to overthrow Queen Mary. He was one of some five hundred alleged conspirators to be captured, tried, and convicted. But while the ringleaders were hanged—many were also drawn and quartered, for good measure—Leonard was among seventy-five men given a reprieve.

We know that Leonard Digges was intrigued by the night sky—but whether he gazed at it with the unaided eye, or had some kind of optical assistance, has been the subject of much debate. Did he invent a primitive telescope, and aim it at the heavens? If he did so, it would have been a full six decades before Galileo—but the evidence is scant. We have only Thomas Digges's account of his father's use of “perspective glasses” for long-distance viewing; supposedly he could read the lettering on coins that had been scattered in a field, and could see what people several miles away were up to. Digges goes on to discuss the “marvellous” things revealed by the use of “glasses concave and convex”; he describes aiming such a perspective glass at a village, from some distance away, and being able to discern “any particular house or room thereof … as plainly as if you were corporeally present.…”

The claims seem to ask to be taken seriously, but many historians are doubtful. Richard Panek, for example, assures us that such instruments did not yet exist. “Despite their seeming certitude, these writings (and many others) were speculations or embellishments.” Richard Dunn describes the evidence as “uncertain,” but concedes that by this time “many people were making investigations with lenses of sufficient quality for a working telescope to be a practical possibility.” Thomas Digges, incidentally, says that he wrote a book on perspective glasses—but if he did, it has not survived, nor have any telescope-like devices from that period. (We will take a closer look at the plausibility of a “Tudor telescope” in Chapter 5.) Leonard Digges died when Thomas was just thirteen, at which point the younger Digges became a pupil of John Dee, one of the most influential philosopher-mystics of the age (and a figure we will look at in more depth in the next chapter). The two men would remain in close contact.

Thomas Digges was twenty-six when the new star of 1572 lit up the skies over England (the same star observed in Denmark by Tycho Brahe). Digges first noticed the star on November 17—six days after Tycho—and began to study the object carefully. The following year he wrote a short treatise on it. His opinion was in great demand; even the queen sought out his views on the new star. Astrological prognostications aside, Digges believed his observations could be used to test the Copernican theory. His own book about the star,
Alae seu scalae mathematicae
(
Mathematical Wings or Ladders
), appeared in 1573, before the star had faded from view. Like Tycho, Digges had managed to measure the parallax of the new star, or, more precisely, to determine that it displayed so little parallax that it must lie much farther away than the moon.

For Digges, measurements of parallax were more than just a clever substitute for a celestial yardstick. The data could also reveal which view of the cosmos—the Ptolemaic or the Copernican—was correct. That's because the distance between the Earth and the other planets (especially Mars) varied by a much larger amount in the sun-centered scheme than in the geocentric picture. With precise enough observations, one ought to be able to settle the matter. Digges was lucky to have access to the best instruments in England, including a ten-foot cross-staff, for measuring celestial angles, devised by a man named Richard Chancellor; when Digges was a young man, he and Dee used the instrument together. We know that Digges was leaning toward the Copernican theory, and certainly admired Copernicus as the greatest observer of his age. Along with his own measurements of the new star, Digges included a data table with the positions of thirteen reference stars in the constellation Cassiopeia, “taken from Copernicus (with the printer's errors corrected).” He also confessed to working quickly in case “by order of the Most Powerful, it [the star] should recede again.” The star did indeed fade in intensity over the next few months. By February 1574 it had finally disappeared from view. Yet interest in the strange apparition continued. Like Tycho, Digges was keen to read everything that astronomers throughout Europe had written about the wondrous new star.

“A LETTER SENT BY A GENTLEMAN OF ENGLAND”

Given that this was nearly four and a half centuries ago, one might imagine that fresh evidence concerning Digges and the new star would be rather unlikely to turn up. A few years ago, however, a British historian named Stephen Pumfrey stumbled across a published letter, apparently written by Digges, on the subject of this very star. The document, which does not give the author's name, is titled “A letter sent by a gentleman of England, to his frende, containing a confutacion of a French mans errors, in the report of the miraculous starre now shyning.” Only one copy of the letter, published in 1573, seems to have survived. It had been dwelling, virtually forgotten, in the library in Lambeth Palace in London. In a journal article published in 2010, Pumfrey presents a compelling case for Digges being the author.

The letter was written in response to another letter, written by another anonymous individual—how much simpler life would be if people signed their names!—living in France.
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The Frenchman is identified only by his (presumably Latin) initials, I.G.D.V. Pumfrey suspects this was the work of an astronomer named Jean Gosselin, who worked in the library of the French king, Charles IX. (As Pumfrey admits, the whole business is a mystery “fit for an Umberto Eco novel.”) We know that the French publication dates from 1572. Obviously rushed into print, it has several pages of observations of the new star, as well as a diagram showing its location. But it is deeply flawed: The author identifies the object as a comet, and states that it displayed a significant parallax.

The Frenchman's letter also provides one of many indications of the profound astrological significance associated with the new star. Although some saw it as a good omen, many feared it was a sign that something ominous was on the horizon—perhaps war, an ever-present danger. That was certainly true in France, a nation already torn by religious strife. Gosselin saw the new star as a sign that God would soon seek out and punish the sinful. He prayed that it would lead people to “mend their bad ways, and in the times to come to live in accordance with the holy law, in the Catholic faith.” Both Tycho and Digges were similarly concerned with the star's astrological significance, which was widely debated in the royal courts of Europe. Were it truly a new star, it would (they believed) be the first since the birth of Christ, when a bright “star” was said to have led the Wise Men to Bethlehem; another such star, it was imagined, might be a sign of the coming Apocalypse. Such beliefs were widespread at the time, particularly by English Puritans, and were likely shared by Digges himself. As late as 1638—more than sixty-five years after the star had faded from view—an English poet named Francis Quarles was still describing the event from a biblical perspective. In one of his epigrams, he draws a parallel between Tycho's nova and the Star of Bethlehem: