Starship Asterisk*

http://www.archive.org/stream/throughspaceandt031585mbp/throughspaceandt031585mbp_djvu.txt wrote:

THROUGH SPACE & TIME (1934)
BY SIR JAMES JEANS

Aratus and star-signs

<<The Greeks and Egyptians had very similar names for many of the constellations of the Zodiac, but the Chinese Zodiac is named after twelve quite different animals. In place of our Ram, Bull, Twins and Crab, they have Dog, Cock, Ape, Ram, and so on. The remainder of the sky has also been divided into constellations, some of which are mentioned by very ancient writers. Orion and the Great Bear are mentioned both in Homer and in the Book of Job, while the Little Bear was described by Thales in the seventh century before Christ. Many of the constellations also are common to many languages and peoples. The Orion constellation, for instance, is often associated with a hunter or hero, and the Taurus constellation with a fierce animal.

All the constellations which could be seen from ancient Greece were drawn on a globe by the astronomer Eudoxus, a pupil of Plato, in the fourth century before Christ, and subsequently described in verse by Aratus. Most of them are associated in some way or other with the legends or fairy tales of long ago either of ancient Greece or of some still earlier civilisation. Thus we read of Helice and Cynosura, the Great Bear and the Little Bear, the latter being a hunter who was changed into a bear so that he should not kill his mother, whom Juno had already changed into a bear out of jealousy; or again of Hercules (whom Aratus describes merely as "The kneeling man") and the dragon; or best story of all, a real thriller of Perseus arriving in the nick of time to rescue Andromeda who was chained to a rock in the sea while Cetus, the sea-monster, was coming to devour her. He made Cetus look at the Medusa's head, which turned everyone to stone who saw it, but escaped this fate himself by looking at it in a mirror. I have heard it suggested that our more modern nursery rhyme, which describes the cow jumping over the moon, was inspired by the sight of the moon moving through, or perhaps under, the constellation Taurus. The little dog who laughed to see such fun would no doubt be Canis Minor, the next constellation. There is also a dish (Crater) in the sky to run away with the spoon.

The Greeks were not great travellers, so that there were parts of the sky south of the equator which they did not see at all, and so could not divide into constellations. It was a pity, for the moderns who named the constellations in this part of the sky did not always maintain the dignity and simplicity of the older names. We find such constellations appearing as the Printer's Workshop, the Painter's Easel, the Engraver's Pen, the Chemical Furnace, and, even more ridiculous, the Honours of Frederick, the Harp of the Georges, the Oak-tree of Charles I. Even more recently a French astronomer, Lalande, tried to insert a cat into heaven. He wrote : * * I love cats ; I adore cats ; I may be pardoned for placing one in the sky after sixty years of arduous labours". But it has since disappeared, perhaps because it did not enjoy the society of its neighbours, Canis Major, Canis Minor, and Canes Venatici.

As Greece lies about 40 degrees north of the equator, the parts of the sky which the ancient Greeks could not see would be those which lay within 40 degrees of the South Pole. We might then reasonably expect that all the constellations with modern names would lie inside a circle 40 degrees in radius, having the South Pole as centre. Broadly speaking, we find that they all lie within a circle of 40 degrees radius, but its centre is not the South Pole. The reason for this is both interesting and informative.

The earth spins in space like a spinning top, but its axis does not always point in the same direction. The bulge round the earth's equator is continually being pulled by the sun's gravitational pull, and as this pull twists the earth's axis round in space, the earth top wobbles, rather as the ordinary schoolboy's top does when it is "dying".

It is found that the earth's axis wobbles round in a complete small circle once every 26,000 years. At the present moment the axis points to the tip of the tail of the Little Bear, but 4000 years ago it pointed to the Bear's left ear, and 5000 years ago to the tip of its nose. And 13,000 years ago the whole Little Bear was well down in the northern sky, while earth's axis pointed near Vega, which is now well down in the sky. Because the spinning top on which we live is rolling about in space, the inhabitants of Greece must have seen different parts of the sky at different epochs just as, when we live on a rolling ship, we see different sights through the porthole of our cabin. This goes some way to wards explaining why many southern constellations, such as the Centaur, have Greek names ; those parts of the sky are not visible from Greece now, but they were 4000 years ago, when people believed in Centaurs.

The constellations which Aratus mentioned in his poem are not even those which the Greeks were able to see at the time of Aratus; they are, broadly speaking, those which had been visible from the latitude of Greece about 2500 years earlier, or about 2800 years before Christ. Thus it seems likely that Aratus merely described constellations which had been named in the first instance by people who resided in the same latitude as Greece, at the period of about 2800 B.C. This points very strongly to the Babylonians, especially as there is other evidence that some at least of the principal constellations had been known to the Babylonians at an even earlier date.>>

http://en.wikipedia.org/wiki/Aratus wrote:

Lunar crater Aratus from Apollo 15.

<<Aratus (Greek: Ἄρατος ὁ Σολεύς; ca. 315 BC/310 BC – 240 BC) was a Greek didactic poet. His major extant work is his hexameter poem Phaenomena (Φαινόμενα "Appearances"), the first half of which is a verse setting of a lost work of the same name by Eudoxus of Cnidus. It describes the constellations and other celestial phenomena. The second half is called the Diosemeia (Διοσημεῖα "Forecasts"), and is chiefly about weather lore. Although Aratus was somewhat ignorant of Greek astronomy, his poem was very popular in the Greek and Roman world, as is proved by the large number of commentaries and Latin translations, some of which survive.

As a disciple of the Peripatetic philosopher Praxiphanes, in Athens, he met the Stoic philosopher Zeno, as well as Callimachus of Cyrene and Menedemus, the founder of the Eretrian School. About 276 he was invited to the court of the Macedonian king Antigonus II Gonatas, whose victory over the Gauls in 277 BC Aratus set to verse. Here he wrote his most famous poem, Phaenomena ("Appearances"). He then spent some time at the court of Antiochus I Soter of Syria, but subsequently returned to Pella in Macedon, where he died sometime before 239/240 BC. His chief pursuits were medicine, grammar, and philosophy.

The purpose of the Phaenomena is to give an introduction to the constellations, with the rules for their risings and settings; and of the circles of the sphere, amongst which the Milky Way is reckoned. The positions of the constellations, north of the ecliptic, are described by reference to the principal groups surrounding the north pole (Ursa Major, Ursa Minor, Draco, and Cepheus), whilst Orion serves as a point of departure for those to the south. The immobility of the earth, and the revolution of the sky about a fixed axis are maintained; the path of the sun in the zodiac is described; but the planets are introduced merely as bodies having a motion of their own, without any attempt to define their periods; nor is anything said about the moon's orbit. The opening of the poem asserts the dependence of all things upon Zeus. From the lack of precision in the descriptions, it would seem that Aratus was neither a mathematician nor observer or, at any rate, that in this work he did not aim at scientific accuracy. He not only represents the configurations of particular groups incorrectly, but describes some phenomena which are inconsistent with any one supposed latitude of the spectator, and others which could not coexist at any one epoch.

Aratus was cited by the author of Acts (believed to be Luke the Evangelist), in 17.28, where he relates Saint Paul's address on the Areopagus. Paul, speaking of God, quotes the fifth line of Aratus's Phaenomena:

• 
  Let us begin with Zeus, whom we mortals never leave unspoken.
  For every street, every market-place is full of Zeus.
  Even the sea and the harbour are full of this deity.
  Everywhere everyone is indebted to Zeus.
  For we are indeed his offspring... (Phaenomena 1-5).>>