Chapter 15

Astrology vs. Astronomy

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Astrology and Astronomy

Astronomy is based on science.  Astrology is based on past ignorance.

Astrology and World War II

During World War II the Allies found out that Hitler was using astrology to plan his battles, and so the Allies know when attacks were to occur.  Using astrology the Allies gained an advantage and this help them win the war.

Constellations and Astrology

Constellations are groups of stars, that have become associated with a figure, and myth. The Big Dipper, the Little Dipper, and Orion are probably the best known and easily recognized constellations in the night sky. There are literally hundreds of constellations. Among these are the constellations of Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius,, Capricorn, Aquarius and Pisces.

Using the sky charts used by most astrologers, the sun is not where it is supposed to be.  For example, according to astrology on August 27th, the sun is supposed to be in Virgo.  It is actually in Leo.

How do I know?  I used the program Stellarium and it shows actually where the sun and planets are really located.  Strellarium is a free download and works on PCs, Macs, and Ubuntu.

Another good program is SkyGlobe.  It will run on XP but not on new operating system.  Using SkyGlobe, I found that the sun was middle of Virgo on September 7th.  I had to travel back to about the year 1000 BC to place the sun in the middle of Virgo.  This was 3000 years ago.

The Planets

Back when astrology was invented, there were only five planets known, namely, Mercury, Venus, Mars, Jupiter and Saturn.  These planets were identified as gods. Their movement against the background patter of starts were regarded as significant and played a key role in many Greek stories.  The planets Uranus, Neptune and Pluto were not known.  Pluto is now demoted as a planet as there are thousands of Pluto like objects just beyond pluto.

Motions of the Earth

The earth has several motions.  It rotates around its axis producing day and night.  It rotates around the sun once every year.  We all know this.  But the earth also precesses.  Precession is the change seen when a top starts to slow down.  The axis of rotation moves slowly in a circle.

The North Pole Star Changes

Polaris is the current north pole star.  About 12,000 years ago it was Vega and about 3000 years ago it was Thuban.  This is due to precession.  

Bad Sky Charts

Astrology is about 3,000 to 5,000 year old and it continues to use astrology charts that are thousands of years old.  As the earth rotates on its axis, the stars move from the East to the West around the point in the sky above the north and south poles.  If the north and south poles are moved, then the motion of the stars change.  

The path of the sun against the stars can be traced by looking at the sun at the same time each day.  Of course the sun makes the stars invisible, so you have to look just before dawn or just after sunset to see which stars are near the sun.

As the earth moves around the sun, the sun traces out a path across the background of the stars.  Each day it moves about one degree.  This amounts to only about four minutes a day.  But this adds up.  Over a year, the sun moves full circle or 360 degrees.

The path the sun makes in the sky is called the ecliptic.  The ecliptic passes through the constellations of Virgo, Libra, Scorpius, Sagittarius, Capricornus, Aquarius, Pisces, Aries, Taurus, Gemini, and Cancer.

The celestial sphere is an imaginary ball that surrounds the earth.  It has a north and south pole.  It also has an equator called the celestial equator.  This celestial sphere also contains all the stars we see.  Think of this ball turning around as we watch the stars rise in the East and set in the West.

Imagine if we moved this celestial sphere in a different way.  This movement moves the north pole in a circle like a toy top slowing down.  This is precession.  The rotation is very slow, and it takes 26,000 years.  Over 3,000 years, there is enough rotation to be really noticeable.  Astrology is older than this.

Most astrology sky charts did not take precession into consideration.  As a consequence, the path of the sun is not correct on their charts.  Their ecliptic is in the wrong place.  The houses are not correct.  For example, on August 27th, the sun is in Virgo, but on a updated skychart the sun is actually in Leo.

Astrology Fails as a Predictor of the Future

If astrology worked even just a little, you could use it to make money in the stock market or futures.  But astrologers do not take advantage of this and instead stay in the business of doing people's charts.  Many scientific studies have been made, and they all show that it is no more accurate than chance would have it in making predictions.

Free Will

If astrology was true, our free will would be secondary to the motion of the planets.


Astrology is very old indeed and began in Mesopotamia (now Iran and Iraq) about 6000 years ago. Some historians think it even older as some astrological artifacts have been dated as old as 12,000 years ago.  

It began as a calendar designed to help the farmers way back then. Farmers have always recognized that there is a difference between the quality of morning and afternoon light. They found that there are certain times when it is best to plant, grow and harvest their crops for maximum growth and quality.

On the whole, it must have been man's reverence for the magical, strange moving lights in the sky. These lights were regarded as gods and the star gods led to the development of astrology. Out of the thick mists that conceal earliest history have come down to us a number of cuneiform tablets--brick and stone slabs inscribed with triangular or wedge-shaped characters--recording the very simplest astronomical phenomena: eclipses of the Moon, certain planetary movements, interpreted as predicting famine, war, peace or plenty.

Babylonia during the 17th and 18th centuries BC was riddled with superstition, and many omens were used and recorded--the bites of certain animals, dreams, patters of bird flight, the appearance of newborn babies. ("When a woman bears a child with small ears, the house will fall into ruin."). Superstitions included such eccentricities as the appearance in one's house of a pig with palm fibers in its mouth.

More About Precession

As we have said, precession occurs when a spinning toy top when it starts to slow down and starts to wobble. The axis of the spinning object wobbles (traces a circle) when a torque is applied to it. The axis of a wobbling top will start to trace a circle in the opposite direction of the spinning object.

Technically, precession is due to a combination of the Earth's nonspherical shape (it is an oblate spheroid, bulging outward at the equator) and the gravitational tidal forces of the Moon and Sun applying force (torque) as they attempt to pull the equatorial bulge into the plane of the ecliptic.

The north pole of the Earth goes around in a circle, making one complete precession cycle in a period of approximately 25,800 years. Over this cycle the Earth's north pole moves from where it is now (within 1 of Polaris) in a circle around the ecliptic pole. Back when Western astrology charts where created, the north pole was pointing close to the star Thuban.


In the centuries centering on the year 2800 BC, the start Thuban was north pole star. About this time, maybe a 1000 years later the Astrology Charts were drawn. For many years there was no north pole star. About the year 1500 AD the star Polaris moved into position (closer than other stars) and could be said to be the north pole star. Polaris will continue to get closer to the North Pole, and will be the closest around the year 2100. Precession is slow and it takes 71.5 years for the earth to tilt one degree.

Precession is caused by the fact that the earth is not a perfect sphere.  Instead the earth is oblate, that its it bulges in the middle along the equator.  This bulge is due to the earth's rotation.  The equatorial diameter of the earth is 43 km or 29 miles larger than the polar diameter.  This amounts to 0.34%.

The force of gravity weakens with the square of the distance.   Both the sun and the moon pull on the earth. Since the earth is tilted in its spin axis in relationship to its orbital plane around the sun, the pull on the earth varies a little. During the summer in the north hemisphere, the pull on the bulge tents to pull up the equator. During the winter the opposite is true.  Both the sun and moon try to straighten the rotation axis to bring it in line with the orbital axis.  The same forces cause the ocean's tides.

Instead of straightening, the Earth rotation axis precesses, and the north pole sweeping  the sky in a slow conical motion that takes 25,800 years to complete a revolution.  The north star Polaris will slowly move closer to the north pole until it reaches its closest point in the year 2100.

Calendar Correction

Not only the Astrology Charts were out of date, precession also messed up the calendars making the holidays shift away from their seasons. Easter was being effected. The pope did something about it. On October 4, 1582 the next day became October 15, 1582. Ten days were skipped. The calendar was switched from the Julian calendar to the Gregorian calendar. Only the Catholic countries followed the order. England did not switch calendars until 1752. All this was due to precession.

More About the Ecliptic and the Zodiac

The word zodiac comes from the Greek word "zoion" meaning animal.

There are two basic types of zodiacs. One is the zodiac defined by astronomy and the other is defined by astrology. Astrology assumes and attempts to interpret the influence of the heavenly bodies on human affairs. Astronomy is the science that deals with the material universe beyond the earth.

Zodiac in Scientific Astronomy

In astronomy, the zodiac is a 8-wide belt in the of the sky that is centered on the ecliptic. As seen from the earth, the sun, the moon, and the major planets all stay in this belt. In modern astronomy, the zodiacal constellations, like all constellations, are recognized as chance visual groupings of stars, with no natural significance.

In astronomy, the zodiacal constellations are aligned to their correct astronomical location. The constellations all take up varying amounts of space along the ecliptic. The zodiac serves as a convenient means of indicating the positions of the heavenly bodies.

Two Schools of Astrology

There are two basic schools of astrology—Western astrology and Vedic astrology and these use different zodiacs. Western astrology uses the tropical zodiac and Vedic (Indian) astrology uses the sidereal zodiac. The differences between the tropical zodiac and the sidereal zodiac are due to precession. The source data used by the two schools is not the same and makes their results vastly different.

Vedic (Hindu) astrology is more scientific and uses the sidereal zodiac that loosely matches modern real world sky charts. This astrology at least knows where the stars and planets are located and places some value on modern astronomy charts.

Western astrology uses the tropical zodiac charts that are somewhere between 2000 and 5000 years old.  It is not based on planets passing through actual celestial constellations, but passing through imaginary houses named for constellations. Western astrology charts are wrong and do not match the real sky.  The positions of the sun, moon and planets have moved during the past 2300 years.

The "ayanamsa" is the distance or the difference between the imaginary Zodiac of the Western astrologers and the true Zodiac of the updated Vedic astrology. The ayanamsa continues to grow at a rate of 50.26 seconds per year. After thousands of years this amounts to about 23 degrees!

This is no trivial matter.  A Virgo in western astrology is a Leo in Vedic astrology.

In western tropical astrology, the zodiacal year begins at the point where the plane of the ecliptic intersects with the earth's equatorial plane at the vernal equinox. This is when the Sun moves into the northern hemisphere of the earth's equatorial plane. Thus the Sun always enters the astrological zodiacal sign of Aries at the vernal equinox about March 20, but it will not cross into the astronomical constellation of the same name until nearly a month later. So in western tropical astrology, although the signs derive their names from the constellations, they are not the same thing.

Both astrology systems are otherwise the same. They divided the belt into 12 equal parts called houses of 30. Each house is named for constellation. These are the Signs of the Zodiac.

The out of date tropical zodiac will coincide with the correct sidereal zodiac in about 25,800 years.

The 13th Sign --Ophiuchus

The astrological zodiacs do not count Ophiuchus as a constellation and thus we have 12 constellations in the astrological zodiac. The astronomers added Ophiuchus as one of the constellations, making 13 constellations around the zodiac. Some astrologers say that Ophiuchus was invented by the Royal Astronomical Society in 1930 to bedevil the astrologers. It is not that simple.

The problem of Ophiuchus is at least nineteen hundred years old, if not more. It dates back to at least the time of Claudius Ptolemy, the Classical father of astrology [c 130 - 170 AD]. Thus, Ophiuchus as a recognized zodiacal constellation predates the 1930 decision by the International Astronomical Union to adopt constellation boundaries by at least 1,700 years.

Ptolemy produced two great works, Al Magest, which charted the heavens, and Tetrabiblos, the seminal work of astrology - a compendium of essentially all the astrological knowledge of the Ancient Greeks. Al Magest contains the earliest Star Catalogue that we still possess.

In Tetrabiblos, Ptolemy treats Ophiuchus as a non-zodiac constellation; he follows the simple, inherited tradition of the twelve part, equal-sign zodiac. However, in Al Magest, Ptolemy actually charts Ophiuchus in the heavens. He looks at the reality of the stars above. He catalogues 29 stars in the constellation. 24 of these he measures to have a latitude above the Ecliptic. But 5 of these he observes have a latitude below the Ecliptic. In other words the figure of Ophiuchus crosses the Ecliptic [the path of the Sun] making it by definition a Sun Sign

Astrology Experiments

When the same astrology chart was handed out to people answering an advertisement for their free astrology chart, 94% said it was accurate. Trouble was all the charts were based on Dr. Petriot who was a mass murder.

In 1971 the Survey Research Center of University of California sampled 1000 adults in the bay area, getting their birthdates and their claimed attributes. The astrology did not correlate any better than chance.

The Australian Skeptics in 1982 collected newspaper horoscopes and found they even disagreed with each other and did not have much consistency.

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Copyright (c) 2013 by George Norwood