The Relationship Between Astronomy and Astrology

Peoples of the ancient world had a strong tendency to see the gods in nature — in the patterns of weather, natural disasters, eclipses of the sun and moon, illness, disease, events of history, and in comets, wandering planets, and the stars.

To them, the study of the heavens was a way to understand — and predict — the will of the gods. A method of diving their intentions and desires, so that humans (and entire civilizations as a collective) could live, act, and plan accordingly.

Many ancient cultures saw their gods in the heavens — naming the wandering stars (planets) after the greatest gods in their pantheon. This practice began with the Sumerians, who named the planets after their gods. To a significant degree, we use those same names today. The deepest traditions and central theology of Greek and Roman religion is intrinsically related to Sumerian tradition. So while we use the Roman names to this day, this began in Sumer more than 5000 years ago.

The movement of the seven stars that wandered through the night sky — Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn — were distinct from all other celestial bodies. This is probably why they were named after their highest gods, and maybe even were believed to be the literal gods soaring around the heavens high above. The exact relationship between the naming convention and their religious counterparts in ancient mythology is unknown.

Most ancient cultures associated the wanderers with supernatural rules of the pantheon, and kept a religiously close eye on them. As I stated before, the Ancient Greeks maintained the naming convention laid down by the Sumerians, Akkadians, Egyptians, and Babylonians. They also attributed to the planets influence the same powers held by the god they were named after. [1]

The are the religious roots out of which the ancient divinatory system of astrology was born. In essence, astrology holds that each planet and important celestial object in our solar system has an energy which influence each person on Earth as an individual, entire civilizations, and humanity as a whole. The specifics of this influence at a given time, is dictated by the relative geometry of the planets with respect to one another around Earth, and with respect to the energy of the zodiacal constellations that they are in.

The Ancient Roots of Astrology

Astrology began more than 3000 years ago in Mesopotamia, the foundations laid in Sumerian times before 2000 BCE, and developed further by their ancestors, the Babylonians, in later years.

(Source [1] says c.500 BCE, however, the authors clearly haven’t studied their history of Mesopotamia.)

The Babylonians believed that the motions and positions of the planets influenced the fortunes of nations and kings. It was used to inform the king on decisions that would effect the nation.

Later on, when the sciences of the Babylonians and Egyptians had been learned by the Greeks, astrology came to influence the entire Western World, and spread to Asia as well. [1] Initially, astrology was a system for understanding how the heavens influenced nations (and those in charge of their governance) but under the Greeks and Romans towards (and after) 0 CE, personal astrology — the heavens influencing the fortunes of the individual — began to emerge.

“By the 2nd century BCE the Greeks democratized astrology by developing the idea that the planets influence every individual.” [1] One of their most important theories, judged by its influence and persistence to this day, is the doctrine of natal astrology — that the configuration of the Sun, Moon, and planets at the moment of birth influence the personality and destiny of a person.

Natal astrology reached its peak with Ptolemy c.150 BCE. He compiled a treatise on astrology called Tetrabiblos, the “bible” of astrology that remains in use to this day. [1]

The Horoscope

The horoscope is the foundation of modern astrology, and the key to natal astrology. A horoscope is a chart of the positions of the Sun, Moon, and planets at the time of a person’s birth, which is believed to be the key to which astrological principles to determine the personality and life of a person.

The word “horoscope” comes from the Greek words hora (“time”) and skopos (“watcher”, “marker”). So the word horoscope means “marker of the time (of birth)” or “marker of the hour”. [1]

A horoscope (natal chart) is created by determining the positions of Sun, Moon, and Planets (ideally) at the moment of birth, rather than just the day of birth, in order to mark the constellation of the zodiac that they are in. (Since the Moon or Sun in particular can actually change “houses” (constellation of the zodiac) over the course of a day.)

When astrology was developed into the form that it still takes today, the zodiac was divided into twelve sectors called signs, each consisting of a 30° region along the equator of the celestial sphere. Each sign was named after a constellation after the constellation of the zodiac that the Sun, Moon, and Planets travel through in their motion across the fixed stars. The signs — Aquarius, Pisces, Ares, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn — are named after the constellation of each region of space.

In astrology, your sign is your sun sign — the constellation of the zodiac that the Sun was in when you were born.

A complete horoscope shows the location of the Sun, Moon, and each Planet in their respective sign of the zodiac. Furthermore, each day the celestial sphere turns making one complete rotation (due to the Earth’s rotation on its axis) causing the entire zodiac to move across the sky from east-west. So the position in the sky, or house, must also be calculated.

Generally speaking, there are standardized rules for the interpretation of a horoscope. It was, after all, originally developed by scientists of the ancient world. Most of these rules used in schools of Western Astrology are found in Ptolemy’s Tetrabiblos.

Each sign, house, and planet — the last acting as a “center of force” — are supposed to be associated with particular matters in a person’s life. [1]

A truly detailed interpretation of a horoscope is very complex — say what you want about astrology, but there is a great number of variables and information that must be factored in to a true “reading” of one’s horoscope. With that being said, there are many schools of astrological thought. While thee are rules to be followed, in the end it is an art — much personal judgement, interpretation, and creativity involved. In essence, every astrologer can have their own opinions and predictions on the same horoscope.

Problems With Modern Astrology

One of the great problems of astrology is that the modern signs no longer correlate with the zodiacal constellation they used to represent in the sky. More than 2000 years have passed since astrology was codified, and due to precessions, the signs and constellations are no longer in sync. Because of precession, we have precession of the equinoxes. As the Earth wobbles on its axis, tracing a great circle in the circumpolar skies once every 26,000 years, we also see a slipping of the zodiacal constellations. If you were to observe the Sun rise in the east every June Solstice for 26,000 years, and take note of the constellation the Sun rises in, the constellation would shift by about 1° every 72 years or so. Consequently, over 26,000 years the Sun rises in every constellation of the zodiac on the June Solstice in a great cycle.

2000 years ago when Western Astrology was codified, the Sun rose in Capricorn in January, Aquarius In February, Pisces in March, and so on. Over the intervening time until today, these constellations have precessed by almost exactly one sign — 1/12th of the zodiac.

Today, the sun sign and zodiac are 1/12th of a phase out of step. If you are born in January, you are generally a Capricorn, except the Sun today rises in Sagittarius in January. If you are an Ares, the Sun is actually in Pisces. If you are a Scorpio, the Sun is actually in the constellation of Libra at the time of your birth, and so on.

This, in my opinion, severely undermines the theoretical framework of modern Western Astrology. (Ironically, it also invalidates the scientific results denouncing astrology too, as you will see.)

Astrology Today

Astrologers today employ the same principles laid down by Ptolemy in Tetrabiblos. However, modern technology has made the process significantly more simple. In the past an astrologer essentially had to be an astronomer: they had to know the stars, keep track of the positions of the wanderers from night to night, and be able to measure their position or compute them mathematically, in addition to cultivating the knowledge of astrology. Today, you can use a computer program that does this for you without requiring the astrology to have any direct experience with the night sky. (I bet there are many who cannot tell Venus from Sirius or Mars by looking.)

Furthermore, Sun sign astrology (as seen in newspapers) is a recent, simplified version of natal astrology. It fits everyone into 12 groups — an attempt that professional astrologers themselves recognize as an untrustworthy attempt due to the vast over-simplification and reduction of what astrology is, historically, all about. Yet this is taken seriously by many people.

Today we have astronomy, astrophysics, cosmology, heliophysics, genetics, psychology, psychiatry, and neuroscience that offers a far more sophisticated — and scientifically validated — body of knowledge for understanding these phenomenon. Although we have yet to understand the physics of consciousness or the relativistic physics of gravitation or quantum mechanics — or the unity between these areas — given what we do know, it is hard to imagine a mechanism by which the celestial bodies can impact the personality or future of an individual. Interestingly, simple gravitational force calculations show that the gravitational pull of the obstetrician delivering a baby is greater than that of Mars acting on that same baby.

Countering this, astrologers often argue that there are unknown (supernatural) forces exerted by the planets on human consciousness. However, like qi and prana, all of our attempts to measure such an energy have been fruitless. (Especially where qi and prana are concerned, many hard scientists have made the attempt.)

Astrology puts a central emphasis on the configuration of the planets at the moment of birth. However, today we understand the significant role that genetics plays in our development as individuals. This in addition to the understanding of the influence of our parents (how they are as people, and the home environment they fashioned for us) as well as our greater school, natural, and cultural environments, all played on our psychological — and even genetic expression and — development.

Birth used to be a moment of magical significance 2000 years ago when astrology was codified in its modern form. Today, the significance of the time or date of birth has waned considerably.

Today, very few well-educated people believe in the predestination of personality or fortune by planetary, astrological influence. Nonetheless, many of the general populace find validity in assessing affinities or personality based on astrology — including making judgements about who to hire, associate with, date, or marry.

While modern astrology no longer lines up with the stars, it does remain an interesting, sophisticated system from our history — even if its basis in scientific fact is no longer there. Moreover, we do have to give credit to astrology, since the religious of astrology in ancient times had a significant impact on the development of astronomical sciences. If ancient peoples were not so concerned with the will of the gods in the heavens, the study of the stars would not have been as valuable, noble, and impactful as it was.

Testing Astrology

The results of hundreds of tests have given the same result: there is no statistical evidence that natal astrology has predictive power. [1]

Effective astrologers today use the language of the zodiac and horoscope, but mostly work as amateur therapists. [1] Interestingly, recent studies have shown that any form of short-term therapy makes people feel better — including astrology or psychics — because the act of talking about our problems (to an attentive listener) is in and of itself psychologically beneficial.

The significant modern interest in astrology has led scientists to perform a range of statistical test to determine its predictive power.

For example, examining sun sign astrology assertions — that one sun sign is more likely to produce leaders, while another, artists or high-calibre athletes, while people of another sun sign are destined for great wealth — we can verify the statistics for ourselves by looking up the birthdays of people in each category.

As you can imagine, the players from the NBA, or great musicians or painters or world leaders or scientists, have birthdays all over the proverbial map. From this perspective, the validity of sun sign predictions is, in essence, non-existent. (My argument here, just one of logic, is that personality is different from professions, first of all, but secondly, that sun-sign astrology is a vast oversimplification of astrology itself. Real astrologers know the great divergence in personality that can occur between individuals born on the same day, because of the number of other factors like the location of the planets in their respective houses and so on. My only point is that sun-sign astrology is not a good barometer. It is like judging physics based on 17th century notions, rather than Quantum Mechanics, QFT, Relativity, and Modern Astrophysics.)

Another example is statistical tests on the reenlistment records of Marines in the USMC, cross-referenced with their birthdays. According to simplified Sun Sign astrology, only a few signs are said to have the personality that would match a true Marine — one who enlisted, then reenlisted — but their birthdays were, again, random. This certainly invalidates sun sign astrology.

However, my argument here on why this is a bad test is that from one I know of military personalities (especially among the special forces) personalities across the board are represented. The more common trait is a sense of duty to their fellow man, the will to make a change in the world and confront evil (so others don’t have to), service to country, and, of curse, the pure love of combat. The people themselves are wildly different.

More sophisticated studies involving full horoscopes calculated for thousands of individuals are, in my opinion, far more damning for astrology. They all agree: not a single astrological system has been effective at correlating astrological aspects with personality (or any of the other life predictions common to astrology like success, fame, love, wealth, health, etc).

Other tests indicate a much more interesting psychological phenomena: that people have a tendency to see what they want to see. (Confirmation Bias in action.)

French statistician Michel Gauquelin sent the horoscope interpretation of one of the worst mass murderers ever to 150 people. He told each person that he sent it to that the horoscope reading was performed exclusively for them. 94% said they saw themselves in it. [1]

Australian researcher Geoffrey Dean reversed the astrological readings of 22 subjects, flipping phrases included in the original reading to their polar opposite. Yet 95% of them agreed that the readings applied to them. [1]

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