Delta of Cassiopeia

Delta of Cassiopeia

In Brief

In several chapters of Ulysses, Stephen thinks of a star, "delta in Cassiopeia," near which an intensely bright new star appeared in 1572, soon becoming visible even in daytime. In Proteus this spectacular astronomical development, known today to have been a supernova, sparks his interest in extraterrestrial life. In Scylla and Charybdis he presents it as an occult announcement of the birth of William Shakespeare. In Ithaca, his mention of the nova prompts the more astronomically informed Bloom to recall several other, less bright ones that were spotted in the second half of the 19th century. All three passages play with the idea that the celestial heavens are intimately connected with life on earth.

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The delta star in the familiar W-shaped constellation of Cassiopeia is actually a binary system (two orbitally locked stars, a phenomenon which Ithaca calls "the interdependent gyrations of double suns") that lies about 100 light years from Earth in the Milky Way galaxy. In the first few days of November 1572, various observers noticed a new star near this old one. The nova grew steadily brighter until, on November 16, it exceeded the brightness of the planet Venus and could be seen by the naked eye in daytime. About a year and a half later, it faded from view. In 1573 the Danish astronomer Tycho Brahe published a book titled De nova et nullius aevi memoria prius visa stella ("On the new, and never before seen in anyone's life or memory, star"). His small tome gave rise to the term "nova," and today the exploded star seen near delta Cassiopeia is often called Tycho's Supernova. Its remnants, less than 10,000 light years away (also in the Milky Way), were discovered by radio telescope in the 1950s.

The nova seized people's imaginations in the 16th century not only because of its brightness but because such things were not supposed to happen. In the regular, clocklike movements of the heavens, novel and unexplained dynamic phenomena like meteors and comets often caused alarm and were interpreted as baleful omens. But such relatively nearby occurrences were encountered relatively often. Farther out from earth, such changes were seldom seen and Scholastic philosophers even asserted that they were impossible. Aristotle had written that beyond the sphere of the moon the heavens appeared to be changeless, and his speculation had hardened into an inflexible doctrine that planets and stars are made of different stuff than our perishable phenomena. Stars simply could not come into or pass out of being. Now one had done so, and Tycho, observing that its position did not change parallactically, argued that it must lie far beyond the orbit of our moon.

In Proteus Stephen seems to associate this evidence that the heavens are as mutable as the earth with a comparable idea advanced in the late 16th century: Giordano Bruno's argument that the universe is full of worlds like our own. Bruno (1548-1600), who was almost exactly contemporary with Tycho (1546-1601), was more a cosmographer than an astronomer. As far as I am aware the 1572 nova did not directly influence his thinking, but it might certainly have encouraged it. In a 1584 work titled De L'Infinito Universo e Mondi ("On the Infinite Universe and Worlds"), Bruno argued that Copernicus' heliocentric theory was correct, that the sun was just one of an infinite number of similar heavenly bodies, that planets like ours revolved around many of those stars, and that inhabited "worlds" might exist throughout the universe. For his troubles the church had him stripped naked in the streets, fitted with a muzzle, and burned alive. (In his diary at the end of A Portrait, Stephen records a conversation with one of his Jesuit instructors, Father Ghezzi, about "Bruno the Nolan": "He said Bruno was a terrible heretic. I said he was terribly burned. He agreed to this with some sorrow.")

Sitting on the seawall rocks, Stephen thinks of the "roar of cataractic planets, globed, blazing, roaring wayawayawayawayawayaway," and then wonders whether planets like our own may exist throughout the universe: "Why not endless till the farthest star? Darkly they are there behind this light, darkness shining in the brightness, delta of Cassiopeia, worlds." On one of these Brunonian "worlds," he supposes, another Stephen may sit looking up at stars never seen from Earth: "Me sits there with his augur's rod of ash, in borrowed sandals, by day beside a livid sea, unbeheld, in violet night walking beneath a reign of uncouth stars." The fanciful conceit reflects Bruno's belief in the transmigration of souls.

Stephen's fantastical star-fictions continue in Scylla and Charybdis, now drawing on popular reactions to the nova. As Gifford observes, "The supernova caused considerable imaginative excitement in Elizabethan England as a sort of Star of Bethlehem, heralding a new birth, the second coming of Christ." In Stephen's telling it heralded the coming of Shakespeare: "What's in a name? That is what we ask ourselves in childhood when we write the name that we are told is ours. A star, a daystar, a firedrake, rose at his birth. It shone by day in the heavens alone, brighter than Venus in the night, and by night it shone over delta in Cassiopeia, the recumbent constellation which is the signature of his initial among the stars." Cassiopeia is said to be a seated queen combing her hair, though the five stars do not really suggest any such shape. Seen as a W, Shakespeare's "initial," the woman is "recumbent"—lying prone. Stephen no doubt imagines Shakespeare thinking of some similar position recently adopted by Anne Hathaway in her bed. 

The connection between terrestrial and celestial affairs intimated in Proteus persists in this and other details. "Firedrake" was one name for meteors in Shakespeare's time, and Stephen implies that like meteors the nova held portentous significance for earth-dwellers. In particular, its appearance near a gigantic W inscribed in the heavens gave young William an occult hint of his greatness. Puzzled by the reference, Thomas Lyster asks, "Was it a celestial phenomenon?," and Stephen suggests that the nova was a cosmically ordained sign: "— A star by night, Stephen said. A pillar of the cloud by day." He is recalling God's leading of his people through the desert in Exodus 13:21: "And the Lord went before them by day in a pillar of a cloud, to lead them the way; and by night in a pillar of fire, to give the light; to go by day and night." 

Stephen's claim is not only outlandish; it is self-consciously sophistic. Shakespeare was born in 1564, so it can hardly be said with accuracy that the new star "rose at his birth." (Given Cassiopeia's perpetual presence in the northern sky, it would not even have risen!) Nor can it be said with accuracy that Shakespeare might have watched the nova during the period of his infatuation with Anne Hathaway: "His eyes watched it, lowlying on the horizon, eastward of the bear, as he walked by the slumberous summer fields at midnight returning from Shottery and from her arms." There is no need for Stephen to make this claim, and his interior monologue shows that he knows it to be false: "Don't tell them he was nine years old when it was quenched." He might well add, "or that he was eight years old when it first appeared." His knowledge of the relevant dates is good, but his biography is a cynical fraud.

In Ithaca, standing outside 7 Eccles Street gazing at constellations with Bloom, Stephen's astronomical conversation piece becomes amplified with some scientific details that one imagines must come either from Bloom or the narrator. The two men are said to have discussed "the appearance of a star (1st magnitude) of exceeding brilliancy dominating by night and day (a new luminous sun generated by the collision and amalgamation in incandescence of two nonluminous exsuns) about the period of the birth of William Shakespeare over delta in the recumbent neversetting constellation of Cassiopeia." Perhaps Stephen does know (despite his earlier statement that the star "rose") that Cassiopeia is "neversetting." From northern latitudes like Dublin's, the constellation's orbit around Polaris is circumpolar, never dipping below the horizon. The information in parentheses, however, seems beyond his ken.

Star "magnitude" has been mentioned earlier in the same paragraph. In the reverse-order scale devised in antiquity, magnitude 1 stars were the brightest in the sky, and magnitudes "up to and including the 7th" were visible to the naked eye. (Authorities would disagree with "and including." Perhaps Bloom is bragging about the power of his night vision.) After the scale was regularized and made logarithmic in 1856, negative numbers were introduced to account for brighter objects, so that Sirius now has a magnitude of -1.46, and the sun -27. By this way of measuring, the planet Venus is brighter than -4, so the 1572 nova might have ranked almost -5.

The "collision" of two stars was one theorized explanation, still current in 1904, of how novae happened. Today, different causes are proposed: gravitational collapse in the core of a massive star, or runaway nuclear fusion in a white dwarf. But stellar collisions can produce tremendous explosions, creating heavy elements from gold and platinum to uranium (supernovae normally produce no elements heavier than iron), and it is thought that they may sometimes trigger runaway fusion in white dwarfs.

The narrative in Ithaca reports that the two men spoke also "of a star (2nd magnitude) of similar origin but of lesser brilliancy which had appeared in and disappeared from the constellation of the Corona Septentrionalis about the period of the birth of Leopold Bloom and of other stars of (presumably) similar origin which had (effectively or presumably) appeared in and disappeared from the constellation of Andromeda about the period of the birth of Stephen Dedalus, and in and from the constellation of Auriga some years after the birth and death of Rudolph Bloom, junior, and in and from other constellations some years before or after the birth or death of other persons." These were actual sightings of novae. In May 1866 one appeared in Corona Borealis (the Northern Crown, also called Corona Septentrionalis) and grew to magnitude 2. Another was spotted in the constellation Andromeda on 17 August 1885 and reached magnitude 5.85 four days later, before rapidly fading. Still another appeared in the constellation Auriga in 1891 and was observed at peak brightness in January and February 1892, when it had an apparent magnitude of about 4.5.

The science is good, then, but the effort to link novae to people's birth dates displays the same tendentious inexactitude encountered in Scylla and Charybdis. The first seems close enough: Bloom was born in 1866, though the novel never specifies a month or day. Stephen, however, was presumably born, like Joyce, in early 1882, three and a half years before the sighting of the nova in Andromeda, and Rudy was born at the end of 1893, two years after the Auriga nova appeared.

What is going on with this proliferation of novae loosely connected to the births of characters in the book? Reading between the lines, as one must do constantly in Ithaca, it seems likely that Stephen has volunteered his heavily mythologized astronomical tidbit and Bloom, who possesses some actual knowledge of astronomy, has responded by naming several other novae. If Stephen, showing Bloom an honesty he did not display in the library, has said that Tycho's new star appeared "about the period of the birth of William Shakespeare" (emphasis added), then Bloom, gamely playing along, may have chosen to mention novae that appeared within a few years of the births of himself, Stephen, and Rudy, as well as others seen "after the birth or death of other persons" who are not specified.

Supernovae—the term was coined about a decade after the publication of Ulysses—were just beginning to be intensively studied in the second half of the 19th century. Although they are thought to occur only about twice a century in the Milky Way (and not all are observed, because of intervening objects), the development of better and better telescopes has allowed astronomers to observe them in many distant galaxies, exponentially increasing the rate at which they are discovered, as the GIF file here graphically illustrates. It is now known that supernova explosions often result in nebulae, themselves known to produce stars, planets, worlds. Joyce and his astronomical persona Bloom are onto something big.

JH 2021
2010 map by Torsten Bronger of the five stars that make up the constellation of Cassiopeia, with Delta (δ) at lower left. Source: Wikimedia Commons.
Page from Tycho's On the New Star (1573), showing the delta star of Cassiopeia (E) and the "nova stella" (I). Source: Wikimedia Commons.
Title page of Giordano Bruno's On the Infinite Universe and Worlds (Venice, 1584). Source: Wikimedia Commons.
Cassiopeia seen in her "recumbent" pose. Source:
Paul Hardy, The Pillar of Fire, illustration in The Art Bible (London, 1896). Source: Wikimedia Commons.
Spectrum chart of the magnitudes of several bright celestial bodies, showing the limit (~7) of what can be seen by unaided human eyes. Source:
Artist's conception of the explosion initiated by the collision of two neutron stars. Source:
2014 photograph of one of the brightest supernovae observed so far in the 21st century, seen at peak brightness of magnitude 10.6 in galaxy M82, about 12 million light years away from earth. Source:
Raviryan84's 2019 animation (click to run) of the exponentially increasing proliferation of supernova sightings between 1885 and June 2019 (the horseshoe arc without dots is the plane of the Milky Way). Source: Wikimedia Commons.