Precession (continued)

Nice Try!

You may want to skip over the following to the next section if you don't enjoy tedious arguments.

I heard a new variation on absolute motion from a siderealist friend of mine recently. His argument seems very convincing on the surface, except for some subtle gaps in logic. I knew he was mistaken, because he was talking about absolute motion, but I must admit it sure stumped me for a few hours until I thought it through again.

Essentially he said: All this "relative motion" and "frames of reference" stuff is interesting in the abstract, but it's obvious that it's really the earth that precesses, not the stars. All you have to do is stand away from the earth out in space and you can see it's the earth that is really moving and the stars are standing still.

I see two main holes in this argument, as is. The first one is the unstated assumption that the person looking at the earth (there always has to be an "observer", since facts don't materialize by themselves) must be at rest. Is the jerk in your rearview mirror that's been riding your bumper for the last 50 miles "really moving" or not? After all, you've been watching him in the mirror for nearly an hour and he hasn't gone anywhere. You may even say, "This jerk just isn't moving!" But when you get down to it, the only observer who can tell if an object is really moving just by eyeballing it, without making any corrections for his own motion, is an observer that is at rest, that has no motion of his own. So my friend's argument has to be paraphrased: When I am at rest, I can see that the earth is moving.

"At rest" is a Newtonian phrase that is totally meaningless in an Einstein world like the one we live in. It's synonymous with standing still, motionless, having an absolute velocity of zero. How can an observer tell if he's really at rest? Maybe, a second observer can back away from the first and see if he's moving or standing still. But here we've reached an infinite regress, since the motionlessness of the first guy is dependent on the second one being at rest also. You simply can't define absolute motion without knowing in some magical way that some object, somewhere, is indeed standing still. Really.

The inability to measure your absolute velocity is not a theory, it's an experimental fact. The 1887 experiement of Michelson and Morley was an attempt to measure the Earth's motion through space. Since everyone "knows" the Earth orbits around the Sun, everyone expected to measure a velocity that changes (if only in direction) with the Earth's annual orbit. Nobody expected a result of "no motion detected, regardless of time of year" -- the Earth appeared to be standing still! In our universe, you can't measure your absolute velocity and you can never know if you are at rest or moving. I didn't say it, Einstein didn't say it, the universe itself said it.

When scientists need to talk about something "at rest", they often resort to the myth of the "fixed stars". Since the sky looks the same night after night, people unconsciously assume the stars don't move. The framework of the stars has become our common sense idea of what a stationary frame of reference is "supposed" to be like. When we say an object is motionless, we're probably thinking "not moving relative to the stars." So our observer "at rest", as described by the myth of the fixed stars, is simply not moving in a frame of reference defined by the stars. Since my friend assumes that the stars don't move when he stands still, this myth of the fixed stars is his second unstated assumption.

Here's the second hole. By using a definition like this for "at rest", you totally bias your observations of who is moving and who is standing still. You are at rest relative to the frame of the fixed stars, so obviously the stars won't appear to move (much). And you do observe the earth to precess, but this is simply a rotation of the earth's poles relative to the stars, not a rotation in some absolute sense. So we can agree that precession is happening, but this doesn't prove the earth is doing the precessing really. It's easy to imagine an observer at rest in a tropical frame of reference tied to the earth's poles and the equinoxes (I'll spare you the details). For him, the stars precess and the earth stands still. It's tough to give up the prejudice that this second tropical observer is "false" somehow, because he isn't "at rest" relative to the stars. But all this is just a circular argument. The only thing my friend has said was: If I can see the stars don't move, then I can see that the stars don't move and the earth does.

The trouble with Occam's razor is that sometimes it gives you some nasty nicks if you don't use it carefully. When all the dust finally settles, absolute motion disappears on the winds and only relative motion remains. All Newtonian arguments have subtle flaws like this, because our universe is not Newtonian. Einstein is maddening, but that's just the way it is.

(Besides, the fixed stars don't "really" stand still -- they orbit around the center of the galaxy!)


Weaving a Zodiac

Let's change gears here for a bit...

It seems everyone who dabbles with astrology at all has their own intuitive notion of what the zodiac is. We tend to think of it as a real and tangible thing that actually exists in the sky. However, as you're probably guessing by now, the underlying story is much more complicated than it may seem to common sense, so let's proceed slowly.

One of the most primitive observations about the sky that is possible for human beings is that things in the sky appear to move (relative to our Earthly point of view). At first, our kind would have first become aware of how objects rise and set each day. After that was mastered, it would become obvious that the Sun and Moon have their own unique motions in the sky independent of the stars. Various bodies were observed to wander around the sky as well. These became known as "planets", from the Greek word for "wanderer". Eventually, with the rise of sciences in the great civilizations around the globe, these observations were put on a firmer, more mathematical basis.

The path of the Sun each year became known as the ecliptic. Because the solar system is rather flat, that is, most of the planetary orbits are in roughly the same plane, it appears to us on Earth that all the planets stay close to the Sun. When you include a small portion of the sky on either side of the ecliptic ("widening the highway", so to speak), it draws out a circular band that was given the name zodiac, from the Greek word for "circle of life" (most of the subdivisions of the zodiac are people or animals). In other words, the zodiac is the celestial stage on which all the wanderers perform their play.

However, like all circles, the ecliptic suffers from two problems when it comes to using it for making measurements. First of all, circles have no beginning or end. All points on a circle look the same. Unlike a finite line, there are no endpoints from which to start measuring distances. You need a starting point of some kind. We'll discuss this problem in the next section on the vernal equinox. Second, you have to know how to divide up the circle into recognizable subdivisions so we can say where a planet is located (i.e., which subdivision is it in). It was only quite recently historically that all these problems were settled, roughly 500 to 300 BCE. And then precession upset these answers.

There's abundant historical evidence that the idea of the zodiac went through considerable evolution over the centuries before settling into its present form. For starters, the concept of the ecliptic had to be understood. When it came to dividing up the zodiac, it was necessary to create "star images" or constellations in the sky, based on mythic images that humans projected onto groups of stars. There weren't always 12 zodiac constellations; older cultures often had more or fewer of these images than we do. In fact, many of the oldest zodiacs appear to be based on lunar motions. These zodiacs typically have 27 or 28 "lunar mansions" (called "Nakshatras" in Sanskrit) along the ecliptic (or equator), based on the daily motion of the Moon (it takes 27.32 days for the Moon to travel around the sky). After settling on 12 constellations, these irregularly sized star patterns needed to be abstracted into 12 equal sized 30 degree divisions of the zodiac known as zodiac signs. It's not until the astrologers of Sumeria and Persia that we get our "modern" zodiac.

So, depending upon the answers to our two questions (Where do you start? How do you divide up the zodiac?), you will get different zodiacs. Each has their own uses and points of view. Each is a perfectly valid way for measuring the positions of the planets. Each affects the way we look at the universe through their geometry and symbolism. Different zodiacs give different answers, but none is inherently "more correct" than another. Maybe...


Tracking the Elusive Equinox

Each year around March 21st, as the northern hemisphere heads into spring, the Sun is at a point on the ecliptic plane where it appears directly overhead at the equator. If you travel to the Tropic of Cancer, at a north latitude of 23 degrees and 26 minutes (the obliquity of the ecliptic, if you remember), the Sun will appear to be overhead at that latitude about June 21, the first day of summer. After travelling from the equator to this tropic, the Sun stands still and heads south again. Around September 23rd, the Sun is over the equator once more as autumn begins. Finally, winter starts near December 21st, as the Sun stands overhead at the tropic of Capricorn, 23 degrees and 26 minutes south latitude. Actual dates may vary a few days, depending upon your calendar (another topic we won't go into here).

The positions of the Sun in the spring and the fall are called the vernal and autumnal equinoxes. The name equinox means roughly "equal nights", because day and night are the same length at these times. The solar positions in the summer and winter are the summer and winter solstices, where solstice means "Sun stands still". The equinoxes, solstices and ecliptic poles, plus the various circles that connect them (one of them is the ecliptic itself), form a huge, elaborate framework for orienting ourselves to the universe.

Since these points are so important to our story, let me directly quote the official definition of the vernal equinox. This comes from a standard reference used by astronomers everywhere, a book called "The Explanatory Supplement to the Astronomical Ephemeris and the American Ephemeris and Nautical Almanac" (hereafter, just "Explanatory Supplement"), the 1974 edition. This book defines all the gory details for performing astronomical measurements and calculations. I quote:

The fundamental astronomical reference systems are based on the celestial equator, coplanar with the Earth's equator, and the ecliptic, the plane of the Earth's orbit round the Sun. The angular coordinates in these planes are measured from the ascending node of the ecliptic on the equator, or the point at which the Sun in its annual apparent path round the Earth crosses the equator from south to north; and they are measured positively to the east, that is in the direction of the Sun's motion with respect to the stars. The ascending node of the ecliptic on the equator is referred to as "the vernal equinox", "the first point of Aries", or simply as "the equinox".

Of course, then it gets messy.

While it's easy to say the equinox is where the equator and ecliptic cross, remember that we're talking about precession here. Both of the equator and ecliptic planes are constantly changing due to precession, so the equinox is constantly changing as well. To be precise, you must refer to the equinox at a given time. Further, precession without nutation gives the mean equator and ecliptic; with nutation, you get the true equator and ecliptic. Therefore, there must be mean equinoxes and true equinoxes as well. Astronomers publish thick books for making all these calculations.

Actually, it's confusing to say the equinox moves. In the official definition, all our fundamental reference systems use the equinox as the zero starting point, so the equinox is always at zero at any given time. However, the equinox at one time period is not in the same position as the equinox of another date. You can only define the motion of the equinox relative to a "fixed" standard, typically the mean equator/ecliptic/equinox of the year 1950 or 2000. Alternatively, you could measure the position of the equinox relative to the fixed stars, but that technique has its own host of problems. It's easier to measure the changing positions of the stars relative to the equinox, not vice versa. Astronomers talk, in practice, of how the stars precess.

The vernal equinox is currently in the constellation (star pattern) of Pisces (moving into Aquarius in a few centuries), but the astronomers still call it the first point of Aries. It used to be in the constellation of Aries about 2000 years ago before moving next door and 4000 years ago it was in Taurus. Back in the Age of Aries, the zodiac signs and constellations of the same names were actually in the same parts of the sky approximately. In our own times, everything is one sign off and it will soon get even worse.

One of the biggest disagreements between astrologers concerns which vernal equinox to use when constructing a zodiac. One school, the tropicalists, uses the current equinox. The siderealists, on the other hand, have chosen a fixed equinox in the past and stuck with it over the centuries. Due to precession, the angular distance between the current equinox and the old fixed equinox is not only non-zero, but is increasing with time. This distance is commonly given the name ayanamsa, a Sanskrit word meaning roughly "degree of the solstice". One of the critical decisions when designing a sidereal zodiac is the proper choice of an ayanamsa formula. There are at present a large number of ayanamsas, each with its own band of proponents, and hence many different sidereal zodiacs.


For background information on astrological symbolism relevant to this section, please see the Help Pages, especially the pages on Zodiac Signs and Planets.

The Symbolism of the Zodiac

Of course, if the only thing astrology did with the zodiac was measure the positions of planets in the sky, this entire argument would be rather silly. The disputes between competing zodiacs would have little more substance than whether it's "more correct" to measure the distance between two cities in miles or kilometers. We'd all just invoke the spirit of relativity and move on to the next topic.

However, astrology didn't evolve that direction. It never was a modern physical science and it never will be. It started out in the mists of history as a study of omens in the environment in order to understand and predict how nature affects people. Over the centuries, it has evolved into a means to understand the psychology of people and the events in their lives (at least in the West), among other things. The way astrology looks at the universe is expressed qualitatively in terms of a very complicated symbolism that borrows from many different areas of experience. We need to take a detour through this symbolism.

The Language of Subtle Energy

Let me outline briefly my working paradigm concerning astrology, if only to help you grasp my model more coherently. At the ground level of my model is something I call subtle energy. In my astrology pages, I'm always talking about "the energies" at a given time. It doesn't matter to me if you think of energies as gods in the sky sitting on majestic thrones, a more diffuse "universal spirit", or even some kind of quantum field effect -- that's why I use such a neutral phrase. These energies operate at different "frequencies" and have different qualities for us. The lowest or densest frequencies are what make up the physical universe, the level that makes an impression on us via our bodies and our sense organs, and the level scientists study via measuring instruments that enhance our senses. At a higher frequency, you experience the energies as emotional ebbs and flows. Still higher are experiences that create the mental realm of thoughts and awareness. Even higher frequencies can exist, even if most people can't tune into these stations, representing various "spiritual" levels. People operate on all these frequencies at once, whether we're aware of these processes or not. In fact, you could quite easily make the assertion that we are these energies.

Up to this point, I have a pretty high confidence in the utility of this paradigm. It's the same working model that I use in my healing work. Energies are a very tangible sensation for me in this work. This model is good at helping me understand odd sensations that I experience, what I'm doing with these energies and how it affects the people I'm working with. It "works", as they say. Whether I "believe" this model is another complicated story.

These same energies make up not only people, but every object we can sense in the world around us. That includes planets in the sky. In my experience, planets affect us via the energy fields that connect us on these subtle levels, just like two people can affect each other. I've also noticed over the years (just like the books tell you) that the quality and intensity of these energies seems to vary depending on the precise kind of geometrical relations between the planets. These influences are described by mythic symbolism appropriate to experiences within the psyche, a kind of code or language for discussing the inner world. It's really a language of energy.

I encapsulate this entire model in the phrase: Astrology is the relationship between the geometry of the heavens and life.

So why is this symbolism important? Because these mythic, imaginative symbols describe "real energies" that have real effects and make significant differences. They give us a predictive ability for understanding qualitative changes that are coming up. It's these symbolic stories that astrologers weave that give us a handle on how to "test" astrology.

Symbolism Related to the Earth's Motions

There are 4 main groups of symbols in astrology: planets, signs, houses and aspects. Of these, two are related to some of the Earth's movements that we've discussed.

The daily rotation of the Earth is represented by the houses of an astrology chart. The 12 houses are sections of the sky related to various mundane "areas of life". There are 4 important points on the zodiac, known as angles, related to the houses. These 4 angles, the Ascendent, Midheaven, Descendent and I.C., are considered critical in describing a person and the circumstances of his or her life.

The Earth's orbital motion around the Sun each year corresponds to the zodiac itself. Again, there are 4 "angular" points in the zodiac to consider, the equinoxes and the solstices. On a very physical level, these points define the 4 seasons of the year (spring, summer, autumn, winter). In addition, the zodiac can be divided up into 12 signs, equally spaced 30 degree segments of the ecliptic circle. Each of these 12 is symbolized by a mythic image in the sky which is interpreted as an archetypal personality pattern or stage of life. Please note that these signs are not the same as the constellations (star patterns) of the same name, except maybe in a sidereal zodiac.

When you look at precession, however, there is no obvious astrological symbol system that is uniquely identified with this motion. The concept of "Ages" is perhaps the closest fit here, but it only seems to repeat the zodiac sign symbolism. The more I think about this state of affairs, the more it seems to me evidence that astrology has yet to fully integrate precession into its system. We'll come back to this later.

Symbolism Connected with the Zodiac Signs

Everybody who has been exposed to sun-sign astrology is familiar with the stereotypes of the signs: Aries is pushy, Taurus is stubborn, etc. In fact, most people don't realize that there's much more to astology than sun-signs.

A sun sign is nothing more than that: the zodiac sign that the Sun was in at birth. As such, it is only one small detail in the full mosaic that is a person's birth chart. It's not even the most important detail. I've been known on occasion to give an entire two hour chart reading and not even mention the sun sign.

More generally, the signs are a backdrop within the zodiac for placing planets. Every planet (and other chart points like house cusps) are going to be in a certain sign. Each planet has an energy of its own, often described in terms of a personality type or in lists of key words and phrases. The role of the sign containing that planet is to modify or color the planetary energies slightly, to put some "spin" on it. No sign is strong enough to completely change the way a planet expresses itself; the planetary energy always comes through. Some astrologers describe the effect of the sign as the costume an actor/planet wears in a play. The costume establishes the role, but the essence of the actor still shines through.

With precession in the picture, there's a possibility of different zodiacs. A planet might be in Leo in one zodiac and in Cancer in another. This is very confusing to people who want to know which sign it is "really" in. It's also a problem for astrologers, because Leo and Cancer are very different energies or symbols. How can you reconcile having two different symbols describing the same person?

Planetary Rulers of the Signs

Another ancient doctrine in astrology is the idea of planetary rulerships, the pairing up of signs and planets that have similar meanings. This actually started out several millennia ago as a very simple and straightforward pairing. It starts with the Moon ruling Cancer and the Sun ruling Leo. The next two signs out (Gemini and Virgo) went to Mercury, the next two (Taurus and Libra) to Venus and so on out to Capricorn and Aquarius under Saturn. It was a bit of a gimmick in my mind, but it seems to line up planets and signs in a fairly reasonable fashion.

Trouble started in 1781, when the planet Uranus was discovered. Since every sign had a planet and every planet had a sign or two, the entry of this newcomer was a bit of a blow to the old notion of rulership. The solution that most western astrologers agree with is to give Uranus rulership of Aquarius, demoting Saturn to a "co-ruler" of the sign (although not all astrologers are comfortable with this assignment). The next trouble maker was Neptune, discovered in 1846. Neptune was made the ruler of Pisces, demoting Jupiter. Then came Pluto in 1930, which took over Scorpio at Mars' expense. Starting in the 1970's, astrologers started using Chiron, tons of asteroids and lots of other cosmic debris. There are big arguments going on as to which signs these new bodies rule, if any. My particular bias is that rulership is an idea that doesn't make much sense anymore and needs a major overhaul, if not abandonment. I tend to take planetary rulers very lightly in my work.

Planets are also said to rule houses. If you look at the "cusp" of a house (the starting point or boundary line for the house), that cusp will have a measureable position on the zodiac and will be in a certain sign. The planet that rules that sign is also said to be the ruler of that house. There is also a "natural ruler" for each house. Matching up the first house with Aries, the second house with Taurus, etc., gives us Mars as the natural ruler of the first house, Venus with the second, and so on.

If that was all there was to rulers, it wouldn't be that important of an issue. However, rulers are used quite frequently in chart reading as a way to tie the planets, signs and houses in one part of the chart to the planets, signs and houses of another part in giant chains of cause and effect. For instance, assume the Sun is in Taurus, Venus in Gemini, and Mars in Leo. Because the Sun rules Leo, there is a link up in the chart between Mars/Leo and Sun/Taurus. Taurus is ruled by Venus, bringing Venus/Gemini in as the next link in this chain. Mars/Leo is viewed as the cause or background of the Sun/Taurus affairs and Venus/Gemini is the final outcome. The areas of life indicated by the houses containing these planets are also linked up. Of course, if you change the signs for these planets by using a different zodiac, all these causal chains morph into a totally different story.

Another usage of rulerships happens in certain calculations, such as the Arabian Points. The best known of the Arabian Points is the Part of Fortune. You calculate it by taking the zodiac positions of the Ascendent, Sun and Moon and running these numbers through the formula:

Part of Fortune = Ascendent + Moon - Sun
(At least during the day; at night, the roles of the Sun and Moon are reversed.) Some of the other Arabian Points have formulas that involve house rulerships. For instance, the point
Part of Substance = Ascendent + 2nd house cusp - ruler of 2nd house
depends on the 2nd house ruler. If you changed zodiacs, causing the Sun, Moon and other points to slide to "new positions" (actually, the same position, but named differently), the Part of Fortune would smoothly slide into its slot with all the other chart points. But a formula like the Part of Substance could jump to an entirely new spot, since the sign on the house cusp could change, causing the ruler to refer to an entirely different planet.

One last caveat. Vedic astrology developed along quite different lines than did western astology. In particular, Vedic astology doesn't use the 3 modern planets. Consequently, the older rulership relations (no Uranus, Neptune and Pluto) are always used. And when working with Arabian Points, which were created long before the modern planets were discovered, it is considered traditional to use the older rulerships.

Whole Sign House Systems

A house system is a set of mathematical rules or formulas for calculating the zodiac positions of the cusps of the 12 houses in a chart. Astrologers love to argue about the "correct" house system to use. There are dozens of distinct systems in use by various astrologers. However, it seems the oldest, most "original" system was a very simple minded technique called "whole sign houses". In a nutshell, look at the zodiac sign on the ascendent and make that entire sign the first house. It's quite likely that some of this "first house" will spill over above the horizon, into territory that most systems consider the twelfth house instead. The next sign after the rising sign becomes the second house, the sign after that is the third and so. It may sound too simple to be true, but some very reputable practitioners swear by its efficacy.

Not only were whole sign houses considered a viable option in the west, they are the most commonly used method in Vedic astrology as well. This may have been non-controversial in the Age of Aries 2000 years ago, but these days it leads to problems. Since the tropical and sidereal zodiacs are offset by an odd number of degrees, the cusps in a Vedic chart and a western chart will be vastly different, even though "whole sign houses" are used in either case.

This is one of the least problematic of the various zodiac issues, to my thinking. As I said, astrologers love to argue about houses.

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