- “There is geometry in the humming of the strings, there is music in the spacing of the spheres.” – Pythagoras
Pythagoras believed that the universe was governed by mathematical laws and that the planets and stars emitted a musical tone as they moved through space. He believed that the distance between the planets and stars corresponded to the length of musical strings, and that the frequencies of their vibrations created a celestial harmony.
We are not capable of hearing this eternal music, created by the movement of the heavenly bodies, but it still affects us. This is the main underliing idea of astrology.
Seven planets are enough
The ancients knew only seven planets because they were the only ones visible to the naked eye from Earth. The seven classical planets known to the ancients were the Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn.
It wasn’t until the invention of the telescope in the 17th century that astronomers discovered new planets beyond the seven classical planets. The first new planet discovered was Uranus in 1781, followed by Neptune in 1846, and Pluto in 1930. Contemporary astrologers rushed to add these new planets to the zodiac, butchering the original order and harmony created by the ancients. In more recent times, astronomers have discovered thousands of other planets beyond our solar system, known as exoplanets. Too many for the twelve signs of the zodiac. It became evident that this effort was futile.
However, there are also those who continued practising the traditional astrology. They don’t deny that there are many other planets in the universe. They simply believe that the “music” of these planets does not affect us any more than loud music in some club on the other side of the city would. In other words, it doesn’t mean that it is not there – it is just too far to be relevant.
Celestial spheres
In ancient astronomy, the celestial spheres were hypothetical, concentric, transparent spheres that carried the celestial bodies, including the sun, moon, planets, and stars. In this model, each planet was associated with a particular sphere that carried it around the Earth. The seven classical planets known to the ancients were associated with the following spheres:
- Moon: The Moon was believed to be carried by the first sphere, which was the closest to Earth and was also associated with the element of Earth.
- Mercury: Mercury was associated with the second sphere, which was associated with the element of Water.
- Venus: Venus was associated with the third sphere, which was associated with the element of Air.
- Sun: The Sun was associated with the fourth sphere, which was associated with the element of Fire.
- Mars: Mars was associated with the fifth sphere, which was associated with the element of Aether or Quintessence.
- Jupiter: Jupiter was associated with the sixth sphere, which was also associated with Aether.
- Saturn: Saturn was associated with the seventh and outermost sphere, which was associated with the fixed stars and the Prime Mover, the ultimate source of all motion in the universe.

The original zodiac
The seven classical planets are assigned to the following zodiac signs:
Sun: The Sun is associated with the zodiac sign of Leo, which is a fire sign known for its warmth, creativity, and leadership qualities.
Moon: The Moon is associated with the zodiac sign of Cancer, which is a water sign known for its emotional sensitivity, intuition, and nurturing qualities.
Mercury: Mercury is associated with the zodiac signs of Gemini and Virgo. In Gemini, Mercury is expressed as communication, intellectual curiosity, and adaptability, while in Virgo, Mercury is expressed as practicality, attention to detail, and analytical thinking.
Venus: Venus is associated with the zodiac signs of Taurus and Libra. In Taurus, Venus is expressed as sensuality, beauty, and material abundance, while in Libra, Venus is expressed as harmony, balance, and social grace.
Mars: Mars is associated with the zodiac signs of Aries and Scorpio. In Aries, Mars is expressed as action, courage, and individuality, while in Scorpio, Mars is expressed as intensity, passion, and transformation.
Jupiter: Jupiter is associated with the zodiac signs of Sagittarius and Pisces. In Sagittarius, Jupiter is expressed as expansion, growth, and optimism, while in Pisces, Jupiter is expressed as spirituality, compassion, and imagination.
Saturn: Saturn is associated with the zodiac signs of Capricorn and Aquarius. In Capricorn, Saturn is expressed as discipline, responsibility, and ambition, while in Aquarius, Saturn is expressed as innovation, reform, and intellectual detachment.
Here is an image I made for another article:

At the bottom of this picture we see that the Sun and The Moon rule only one constellation. The rest of the planets rule two constellation each, and they are facing each other on the wheel of the zodiac.
The music of the Spheres
It is not a secret that the twelve constellation and twelve musical notes are connected. It is just not very often that we see how.
The first step is to understand how the planets relate to the musical notes. And here the ancients simply followed the order of the spheres we described above. It starts with the Moon, being the closest to Earth, and it ends with Saturn, who lies in the last, seventh sphere.
- Moon – C
- Mercury – D
- Venus – E
- Sun – F
- Mars – G
- Jupiter – A
- Saturn – B
Now, the easiest way to relate this to the constellations of the Zodiac is to show it on a piano.

First, we assign the planets to the musical notes, according to the list provided by the ancient authors (here shown in red). After that, the zodiac signs are easy to determine. As we saw, except for the Sun and the Moon, each of the planets rules two constellations – one for the light part of the year, and the other for the dark one.
This is how the zodiac signs and planets relate to the musical scale. But there is more.
Days of the week and the Circle of fifths
In astrology, each planet is associated with a particular day of the week. However, if we follow the same order of the accending spheres that we just described, we get something like this:
- Monday – Moon – C
- Wednesday – Mercury – D
- Friday – Venus – E
- Sunday – Sun – F
- Tuesday – Mars – G
- Thursday – Jupiter – A
- Saturday – Saturn – B
On the other hand, if we rearange the days, so that they follow their usual order, we get a random set of notes.
- Monday – Moon – C
- Tuesday – Mars – G
- Wednesday – Mercury – D
- Thursday – Jupiter – A
- Friday – Venus – E
- Saturday – Saturn – B
- Sunday – Sun – F
However, this order is only random at the the first glance. What it actually represents is the Circle of Fifths.
The Circle of Fifths is a diagram that represents the relationships among the twelve tones of the chromatic scale, their corresponding key signatures, and their associated major and minor keys. The circle is arranged clockwise and contains all of the notes in the chromatic scale, with each note separated from its neighbors by an interval of a fifth (or a fourth, depending on the direction you travel around the circle).
Starting from any note on the circle, you can move clockwise to the next note by going up a fifth (or down a fourth), and you can move counterclockwise to the next note by going up a fourth (or down a fifth). This pattern repeats until you have returned to your starting note.
The circle of fifths is a useful tool for musicians, composers, and music theorists to understand the relationships between different keys, and to create chord progressions and modulations in their music.
And indeed, if we start from the note C, and and then move clockwise, the first seven notes match those depicted by the order of the days of the week: C, G, D, A, E, B, F.

Music of the Decans
Decans are a system of dividing each of the 12 zodiac signs into three equal parts of 10 degrees each. As each zodiac sign spans over 30 degrees, this means that there are 12 x3, or 36 decans in total. Each decan is ruled by a different planet and has its own set of characteristics and meanings. This means that besides the ruling planet of each sign, there are also two other planets of minor importance for each of the constellation of the zodiac.
Ancient Egyptians used decans. One of the earliest known depiction of decans is from the tomb of Pharaoh Seti I (c. 1279–1213 BCE) in the Valley of the Kings, where a depiction of the decans can be seen on the ceiling of the burial chamber. In art, decans were usually depicted as boats carrying three deties, with the dominant one in the middle. Ancient Egyptians believed that just as the Sun travells through decans over the course of a year, human soul travels too, in the afterlife. The Book of Nut explains decans in great detail.
Decans were also practical for daily observations of the stars. As every astronomer knows, the width of one finger of a streched arm equals two degrees on the night sky. Therefore a palm of the hand would determine a decan (5 fingers x 2 degrees), and three palms is the width of one constellation of the zodiac.
Starting with Aries, the list of decans and the corresponding planets goes as follows:
- Aries: Mars, Sun, Jupiter
- Taurus: Venus, Mercury, Saturn
- Gemini: Mercury, Venus, Saturn
- Cancer: Moon, Mars, Jupiter
- Leo: Sun, Jupiter, Mars
- Virgo: Mercury, Saturn, Venus
- Libra: Venus, Saturn, Jupiter
- Scorpio: Mars, Sun, Venus
- Sagittarius: Jupiter, Mars, Sun
- Capricorn: Saturn, Venus, Mercury
- Aquarius: Saturn, Jupiter, Mars
- Pisces: Jupiter, Mars, Moon
Now, as you may guessed, we can turn these planets into notes and see what kind of music do the decans make.
- Aries: G, F, A
- Taurus: E, D, B
- Gemini: D, E, B
- Cancer: C, G, A
- Leo: F, A, G
- Virgo: D, B, E
- Libra: E, B, A
- Scorpio: G, F, E
- Sagittarius: A, G, F
- Capricorn: B, E, D
- Aquarius: B, A, G
- Pisces: A, G, C
One way to see this is as a melody of 12 bars, in a 3/4 rhytm, where each note is a quarter long. I tested it and it sounds really interesting.
In the previous chapter, we saw how the ancient tuning of the A note to 432 HZ matches the numbers obtained from the astronomical precession. We also saw how the numbers 36, 72, 108 and 144 related to the most common tempos in music. In this chapter we added the notes and the harmony. It is a window to the way the ancients saw the music and the universe, a reflection of the balance and the harmony we seem to have lost.