Star Lore Of All Ages/Cetus
Cetus
The Whale
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The Whale
spouts aquatic columns to the gale;
Sports on the shining wave at noontide hours,
And shifting rainbows crest the rising showers.
Darwin.
Though Aratos and others connect the Whale with the story of Perseus and Andromeda, there is little doubt that the constellation antedates the time of Perseus.
In earlier times it seems to have been regarded as some kind of leviathan, without connection with the story of the sacrifice of Andromeda. Allen suggests that it may have represented the ferocious Tiamat of the Chaldean myths. In all delineations it has been a strange and fierce marine creature, unlike any known to man, and totally unlike the figure of a whale.
According to Pliny and Solinus, after the monster's encounter with Perseus, in which it suffered from the petrifying gaze of the Medusa, its bones were brought to Rome by Scaurus. Saint Jerome corroborated this story, claiming to have seen the bones of the monster at Tyre.
Brown tells us that Cetus signified "the chaos of the deep" to the Babylonians. It represented primarily the state of chaos "when the earth was waste and wild and darkness was upon the face of the deep." Aratos called it "the dusky monster."
Cetus is sometimes represented as swimming in the river Eridanus, or river Po, the celestial stream into which the venturesome Phaëton was hurled by the bolts of Jove. Burritt depicts the creature with the two front paws immersed in the River, and the constellation lies between this great stream and the flood which pours forth from the jar of the Water Bearer into the gaping mouth of the Southern Fish. Cetus is thus situated appropriately in that region of the sky known to the ancients as "the Sea," alluded to in a previous chapter, a part of the sky where marine symbols abound.
It has been suggested that these constellations, which might well be designated "the marine group," arranged here together, might have reference to the rainy season, or a period of flood when the sun was in this region of the heavens.
Brown points out the interesting fact that the southern heavens are generally given over to creatures of ill significance. Here we find Hydra, Scorpius, Lupus, Corvus, Canis Major, and Cetus. Design rather than chance seems evident in this arrangement.
In the 17th century Cetus was considered to be a symbol of Jonah's whale, and also of Job's leviathan. Dr. Seiss regards it as the old Serpent, which is the Devil and Satan.
A popular name for this constellation is "the Easy Chair," as the arrangement of its stars suggests to the imaginative a reclining chair. A mutilated hand is also seen by some in the star group forming the head of the creature. The five stars in the head of the whale, α, γ, ξ, μ, and λ, form a fairly regular pentagon, which serves as a ready means of identifying the constellation.
The arrangement of the stars in Cetus permits of many geometrical figures being formed. The stars ζ, θ, τ, η, and ι Ceti form an inverted dipper, a little larger but otherwise not unlike the so-called "Milk Dipper" in the contstellation Sagittarius.
The body of the creature is kite-shaped, and the entire constellation somewhat resembles the figure of the prehistoric ichthyosaurus.
Although Cetus is the largest constellation, it contains few telescopic objects of interest. The south pole of the Milky Way is located within its borders, and the constellation "is a condensation point of nebulæ, directly across the sphere from Virgo, also noted in this respect."
Alpha Ceti is no longer the lucida of the constellation, as its Greek-letter name would indicate, for it is inferior in brightness to Beta. One or both of these stars have therefore changed in the course of time. Alpha is well worth observing as a fine combination of a beautiful 2.5 magnitude orange-coloured star with a 5.5 magnitude star of a decided bluish tint. The Arab name for Alpha is "Menkar," meaning "the nose." λ Ceti also bears this name, and as it is situated exactly in the nose of the creature it seems more appropriately named than Alpha. Astrologically Menkar denoted sickness, disgrace, and ill fortune, with danger from great beasts.
β Ceti was known to the Arabs as "Diphda" or "Deneb Kaitos." Diphda signifies "the Frog," and this star was called "the Second Frog," the first one being represented by the star Fomalhaut situated in the mouth of the Southern Fish. The name "Deneb Kaitos" means "the Tail of the Whale toward the South." In China this star bore the strange title of "Superintendent of Earthworks."
No account of the constellation Cetus would be complete without a reference to the wonderful variable star Mira, or Omicron Ceti as it is generally called by astronomers. Historically it is the most interesting of all the variable stars of long period, and it bears the distinction of being the first star whose variability was discovered.
D. Fabricius observed it early on the morning of the I2th of August, 1596, as somewhat brighter than α Arietis. In October it had disappeared. He observed it again in February and March, 1609. Holwarda observed it in 1638, and recognised its periodical variability.
According to Argelander's calculations its period is 331½ days, but it is very irregular, and the difference of period is sometimes as much as twenty-five days. Its magnitude at maximum also varies greatly. At times it vies with stars of the second magnitude, and often it only attains a brilliance of the fifth magnitude. At minimum it is generally of the ninth magnitude, only a thousandth part of its greatest brilliance, and one twentieth as bright as the faintest stars visible to the naked eye.
Mira is of a deep red colour and gives an interesting spectrum. Espin points out a similarity between the spectrum of Mira and the celebrated Nova Aurigæ. Herschel notes an observation of Omicron Ceti on the 6th of November, 1779, when this wonderful star equalled Aldebaran in brightness.
The amateur astronomer with a telescope of 3″ aperture or better can observe very well all the changes in light that take place in this remarkable star. Change seems to bespeak life, and hence the observance of variable stars must ever prove a source of fascination and wonder to those who make a study of them, for they, of all the seeming lifeless orbs that gaze so steadfastly on the centuries, exhibit inherent qualities that distinguish them in the firmament as man is distinguished on earth.
For three centuries this star has been under observation and as yet shows no sign of relaxation. No satisfactory theory has yet been found to account for all the variations in the light of these long-period variables. It has been suggested that the irregularities are caused by the phases of some general law, like the law of the maxima and minima of sun spot activity.
τ Ceti is one of our nearest neighbours in space, its distance being estimated as nine light years.