THE APPEARANCE OF THE CONSTELLATIONS
Despite the fact that the zodiac is not a material object, it is stiff related to a band around the sky. And it is always interesting to discover among the stars one’s own particular sign. The four diagrams included in this article depict the actual constellation of the zoaiac, ana the celestial equator.
The zodiac is an idea in the mind of the human race, and not a material object; yet it is related to a band around the sky. And since it is always interesting to discover among the stars one’s own particular sign, four diagrams are included here showing the actual constellations of the zodiac, with a few neighbouring stars to help identification, and the celestial equator. The central line of the zodiac is called the Ecliptic, and is the line along which the Sun passes, taking just under 3651/4 days to complete the circle. This line is exactly the same every year, and perfectly straight. Its most northerly point is the summer solstice, where the Stm is on the longest day, and this falls at present in the constellations of the twins, Cancer (diagraml), but in AD. 0, it fell in Gemini, as the picture shows, and when the earliest pyramid was built (King Zoser’s step pyramid at Saqqarah, in the twenty- eighth centtlry B.C.) it was in Leo, at the spot marked on (Diagram 2).
The most convenient marker for following the course of the zodiac is the Moon, and when full, she is right opposite the Sun, so the full Moon at the summer solstice marks the place where the Sun will be at the winter solstice, and vice versa. The Moon, however, does not always follow exactly the same path; she can be over 5 degrees north or south of the central line, and this means that she passes sometimes below and sometimes above the brightstars in the zodiac. And just occasionally she passes clean over one of them, as on the night of 16th November 1959, when she passed clean over and hid the star Aldebaran, which is the great red eye of Taurus, the Bull.
A sign of the zodiac looks quite different with a planet in it, for the planet is usually brighter than any of its stars. Planets, like the Moon, vary in brightness from time to time, according to the angle at which we see them. Mars in the south at midnight is very bright and red because he is opposite the Sun and therefore fully illuminated, just like the full Moon; but two months later he is much dimmer and not so obviously red. A brilliant planet in the west or south- west after sunset is usually Venus, and sometimes Jupiter. Venus can never be more than 48 degrees from the Sun, so she is always either the evening star or the morning star, or else, when very close to the Sun, invisible altogether. Mercury is almost always invisible, except in clear climates with no street lighting, because his maximum distance from the Sun is only 28 degrees; so he too can only be seen at dusk and dawn.
Saturn is white, but unlike Jupiter and Venus is not more bright than a first magnitudede star. Like Jupiter and Mars, Saturn first appears in the east one day before sunrise, and as the months go by, passes slowly across the sky from east to west, rising roughly four minutes earlier every day until, after over a year, it is seen for a week or two in the west at dusk and then is lost in -the sunset glow. Then it is in conjunction with the Stm and cannot be seen. (Just for grammatical convenience the planets are sometimes spoken of as ‘he’ and ‘she’; these pronouns are less ambiguous than ‘it’, in sentences where more than one planet is mentioned.)
The twelve constellations of the zodiac take their him to be visible after sunset in the east and at midnight in the south, but this happens at that time of year when the Sun is in the opposite sign. Aries for instance, holds this position in October, Taurus in November, Gemini in December and so on all the way round. But a constellation cannot be seen at all when it holds the Sun, so it is useless to look for Aries in April and May, or for Taurus in May and June. And just after the Sun has passed through it, your constellation is only visible in the early morning.
The constellations vary, off course, in brightness, and also appear to vary in size; indeed it is sometimes stated in books that some are bigger than others. But the zodiac originated in the first millennium B.C. as a calendar, and it was expressly devised to consist of twelve equal divisions, each 30 degrees long. So if astrologers say that the constellations are unequal, they are mistaken. In the original form, which is what counts for purposes of being born under them, they were of equal length. But because the stars are not distributed evenly in the sky some groups do look bigger than others; for instance, the noticeable part of Aries consists of only three stars, while Pisces, with no bright stars at all, stretches quite a long way; and hence unequal divisions between the constellations grew up later.
On Diagrams 1-4, the 30 degree divisions are marked by the signs 00 I, 00 8 and so on. But these are not the same divisions as astronomers use, so it is not surprising that two stars which are now classified in Leo (Epsilon and Mu) fell originally in Cancer, and that two or three which are now put in Pisces (especially Alpha and Eta) overlap into Aries. There is, however, no disadvantage in being born under a constellation which, compared to some of the others, looks small and dim.
To find a particular constellation, one must of course start from some bright and obvious group, and this may mean waiting until a suitable time of year. The best known of all constellations is the Wain, Plough or Big Dipper, but it stands a good way north of the zodiac and the only sign of the twelve which can be found from it is Leo, or by passing through Arcturus, Virgo. This can best be done at midnight in March, or two hours earlier in the night for each month later in the year.
The next most famous constellation is Orion. It lies across the equator and a little way south of the zodiac, under the feet of Taurus and Gemini, so it makes a useful reference point. This is one of the brightest areas of the sky, for of the twenty brightest stars no less than seven are here Betelgeuse and Rigel in Orion, Sirius and Procyon to the left of him, Aldebaran in Taurus, Pollux in Gemini, and Canella overhanging the others from the north.
The brightest stars in the zodiac are those from which it was originally measured, namely Aldebaran (the Bull’s Eye) in 150 of Taurus, Regulus (the Lion’s Heart or the Little King) in 50 of Loe, Antares (the Scorpion’s Heart) in 150 Scorpio, and Spica (the Ear of Corn in the Virgin’s hand) in 290 Virgo. These are respectively the fourteenth, twentieth, seventeenth and sixteenth in brightness, of all the stars in the sky. Pollux, which comes fifteenth in order, was not originally used, nor was Castor, which was brighter then. And Sirius, the brightest of all, was not used either, because like the other brightest stars it lies outside the zodiac. The ancient Egyptians used Sirius, indeed it was the fixed point of their whole calendar, but then they did not at that date use the zodiac; and Sirius rose just in time to announce the annual inundation of the Nile.
Aries, the Ram, is not a conspicuous constellation (Diagram 4). It is most easily found either from Taurus to the left of it or, if Taurus has not yet risen, from the great square of Pegasus on its other side. The only noticeable part of it is the three stars of the head, which mark respectively its eye, nostril and mouth. Their names are Hamal (an Arabic word for sheep), Sharatain (‘the two marks’), and Mesartim, and their shape is better seen from the diagram than described. Aries rises at sunset at the end of October and reaches the south at midnight in the same period.
Taurus (Diagram 1) does not much resemble a bull, nor indeed anything else, but it has two obvious features, the Pleiades and Hyades. The Pleiades is a large but tight cluster of little stars of which only six are clearly distinguishable to most people, though there are dozens of others, so the effect is slightly foggy. The Hyades follow, 8 degrees to the left. They form a V of five stars, some of which are double, and the upper one on the left is a large red one called Aldebaran, also called the Forecaster, of great importance in Babylon because it represented the Tablet on which the gods inscribed the fates of men. There are two other fairly bright stars (though not of the first magnitude) on the tips of the horns, E1 Nath and Al Hecka; they extend quite a long way to the north- east, and lie between Capella (the fifth brightest star, in Auriga) and Orion’s head.
Only the forepart of the Bull is shown on star atlases; the hind part is omitted to leave room for Aries, and has been ever since Greek times. Doubtless this is because the triangle of the Hyades could be compared to the Bull’s face with the horns rising up as far as E1 nath and Al hecka. Yet the name is plainly not derived from the shape; for the ploughing season in Babylon was marked by the Moon being full in this constellation; and the Babylonian Plough, drawn by an ox, was not the Wain, but our small constellation Triangulum, over the head of Aries. The pleiades represented a tuft of hair on the shoulder which most bulls do not have. And in any case the Babylonian bull was smaller than ours, otherwise the earliest babylonian zodiac could not have contained eighteen signs instead of twelve.
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