ASTROLOGY

An approach to the analogy between astrological aspects and acoustic physics

by Sergio Blostein 2025

The purpose of this paper is to attempt to align the existing criteria between astrology and acoustic physics and to guide us toward observing the phenomenological affinity that exists, specifically, between sound, in terms of harmonic complexity, and astrological aspects.

We say that sound is a vibration that propagates in the form of waves and is perceived by the human ear. This is one of the most widely used definitions.

Sound waves, as a physical phenomenon described from the perspective of acoustics, have characteristics such as periodicity or frequency, amplitude or intensity, and timbre or harmonic complexity.

We define the concept of timbre as a natural phenomenon related to the unfolding of the so-called harmonic series, which is a succession of frequencies whose vibrations, measured in Hz (cycles per second), are exact multiples of the series of natural numbers (1, 2, 3, 4, 5, etc.), with the principal frequency or first harmonic being the original sound.

For example, if the original sound has a frequency of 100 Hz (100 cycles per second), the higher harmonics will unfold and be heard along with this basic frequency, decreasing in intensity as the series increases in the number of harmonics:

It’s a unique quality, inherent to what happens as an acoustic phenomenon existing in every sound, which makes the same frequency, pitch, or musical note have different and distinctive characteristics whether they come from a flute, a clarinet, a guitar, or a violin, for example.

What happens and differentiates each of these notes, depending on the source, is the configuration with which the harmonic sounds are superimposed.

With what intensity, with respect to the original sound, and at what moments these harmonics appear and also fade away. Even if there were a particular exacerbation or omission of some of the frequencies in the harmonic series.

This is closely linked to the way the sound is emitted, the constructive characteristics of the instrument, the material it is made from, etc.

All are sound, and this is so because the laws that define it are followed.

Furthermore, this phenomenon is intertwined with the perceptual ability that links us to that information, which is the ability for hearing.

Although the variables are subjective and specific, we can affirm that sounds are perceptible as such within a range between 20 and 20,000 Hz (cycles per second).

Are there frequencies above and below this range?

The answer is: Yes, although we cannot hear them. Our physiology doesn’t allow it.

Above audible frequencies are ultrasounds, and below them are all oscillatory phenomena, regardless of their periodicity or taking into account any limits.

Let's analyze the acoustic behavior of an inaudible sound, one that is not within that frequency range, whose periodicity for each wave is, in this case, one oscillation every 12 years.

We’d be investigating, in this hypothetical case, "the sound" of Jupiter.

Something we’re unable to perceive through our hearing, but which undoubtedly obeys identical physical laws and which, perhaps, we perceive through some other sensibility.

This frequency does not escape the characteristics inherent to all oscillatory phenomena. It therefore has periodicity, amplitude, and timbre complexity.

Its harmonics are also expressed through an arithmetic relationship, according to the series of natural numbers.

Every unit functions and unfolds in the same way, regardless of its periodicity or frequency. As above, so below, once again.

Any circular field also possesses this quality, simply by virtue of being able of recording periodicity and frequency.

For Astrology, the Zodiac is an organic unity, as is the completeness of the circle, as are the circles of the horizon and the equatorial.

All of them behave according to the laws of acoustic physics and therefore have "timbral complexity," that is, the presence of sensitive points able of materializing enough energy for a harmonic to manifest.

Thinking of the cycle in this way, the original sound would be the first harmonic, equivalent to a complete cycle.

The second harmonic, of lower intensity, would be the one that occurs halfway through the cycle, the third in the third part of the cycle, and so on, dividing the unit or cycle by the entire series of whole numbers.

And each of these harmonics is, in turn, able of generating the same series, taking each of these obtained units as the beginning of a new series.

Let's remember at this point that there’ll be a superposition of systems that will weaken in intensity as we move away from 1 and progress through the series of natural numbers.

And for this reason, some of the points into which we divide the unit will be strengthened when a superposition of harmonics occurs.

We’ll always keep in mind that, as we move away from 1, the intensity will decrease, and whenever there’s overlapping of coinciding harmonics, the intensity will be reinforced and therefore expressed more strongly.

Just as we graphed what happens with audible frequencies in a table, we’ll now do so with divisions of the circle/cycle/unit:

Perhaps with this criterion, Hindu astrology considers that certain planets are susceptible to certain aspects and not others, and that in this characteristic they differ from other planets.

But leaving these complexities aside and assuming, for the purpose of this essay, that all planets and points possess the same ability to generate aspects both in the cycles they form and in the circular field in which they’re inscribed, we could hypothesize a certain order of intensity in astrological aspects.

We could assume, "Newtonianly," that each harmonic level that expresses itself will do so in inverse proportion to the square of the distance of the harmonic examined from the first or fundamental harmonic (conjunction).

For this evaluation, we used six series with their respective intensities as the most representative of what actually happens in an infinite array. We consider this decision completely arbitrary, but quite interesting when examining the results and conclusions thus obtained:

Let us observe, then, how the table is rearranged, if we take as the ordering criterion the sum of intensities of concurrent harmonics, in decreasing order:

The reordering is suggestively consistent with the criteria generally accepted for evaluating the relative intensity of astrological aspects, and the distinction between major aspects and other aspects is also very clear.

This places the square with greater intensity relative to the trine, which is earlier in the series, since the square is a harmonic, both in the series originating from the conjunction and in the series arising from the opposition or second harmonic, when we consider it as the first harmonic of a new series.

Of course, there are issues pertaining to the specific quality of each aspect that I consider irrelevant for this quantitative assessment, but which are valuable from an interpretive perspective.

This reordering also reveals the importance of the 30° aspects (semi-sextile and quincunx), which ascend several rows in this chart, due to the large number of overlapping harmonic series.

Incidentally, the 12th harmonic, or the division of unity into 12 parts, synthetically demonstrates the importance of this number, which is the basic seed of the division of all unity into zodiacal fields.

12 is a number that, in the series of natural numbers, notably contains the largest number of submultiples, and if we continue progressing in this series, there’s no milestone that surpasses it.

The orb is also a technical question in Astrology to determine what tolerance is considered effective for an aspect ratio.

We can conduct an experiment to see what acoustics tells us about this.

If we place a finger on a string of an instrument right in the middle of its length without applying pressure, only with minimal contact, a node or standing wave is generated. And if we pluck the string, it’ll be inhibited from vibrating entirely and will only vibrate in its halves. This is because by inhibiting the first harmonic or fundamental, the sound corresponding to the entire length of the string will not be able to vibrate, but both halves will, adding the frequencies produced by the series of harmonics generated by these halves.

Absolute precision is not necessary for this effect to occur, and there’s a certain tolerance on both sides of the exact point of the node, which is perfectly comparable to the orb criterion used in Astrology to evaluate the effectiveness or ineffectiveness of an aspect.

In acoustics, this depends on variables to be considered, such as the proximity of the harmonic produced to the first harmonic (the further away from the 1, the lower the tolerance or orb). And again, these are very difficult issues to evaluate and apply to Astrology, such as, for example, what material the vibrating object is made of (an oscillating element, for acoustics; a celestial body or point, for Astrology).

Here we no longer have any possibility of theorizing about orbs with precision, but we can also observe something very interesting. In both acoustics and Astrology, this tolerance or orb gradually decreases with distance from unity, and this is literally applied according to the location of the harmonic being evaluated, relative to the series.

This means that an opposition is evaluated with a larger orb than a sextile, for example.

Also, beyond the symbolic, a celestial body or point can have a larger or smaller orb than another.

Applying this criterion in acoustics, it can be experimentally observed that for the third harmonic, the orb is larger than for the fourth harmonic.

We could infer, then, that the orb of a trine is larger than that of a square, and there’s no argument to suggest otherwise.

It’s also the case that, for each division, by generating its own system of harmonics, the previously described concurrences occur, which makes the square, as an aspect, of greater intensity, regardless of its quality. It must be said that we’re leaving out of this analysis the systemic correlation between aspects and the division of the circle, whether zodiacal or domal.

Nor are we making any reference to the evolutionary appreciation of every aspect that, originating in the conjunction (0°), dynamically traverses the entire circle, passing through all the aspectual nodes in an order that corresponds to the angles they make with the point of origin until completing the cycle, reaching a new conjunction.

Let's locate the sequence of harmonic nodes on points of the circle, in order, with their corresponding intensity values for each. It's not necessary to exceed 180°, since from 180° to 360° the nodes follow one another in a mirror image, relative to the first half of the circle.

If we establish an orb criterion on both sides of each node, and if, in addition, this orb were proportional to the intensity of each node, we find something very coherent:

None of the nodes (orbs included) listed here overlap or superimpose any of the adjacent nodes, including their orbs.

This generates a system of successive energies throughout the entire circumference, whose coherence allows for the expression of each node individually, according to its own intensity.

The following is a graph that gives us some idea of what happens to the intensities of the aspects (nodes) along the semicircle. The graphed proportions of the intensities are speculative:

Which would be equal to:

Original article here (Spanish language). To contact the author, please write to sergio.blostein@gmail.com.