Disharmony of the Spheres 

Nooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo…

This scream of pain delivered with the intensity of a banshee wail came from the poor, suffering HISTSCI_HULK upon reading an essay on The Conversation (Europe), A hymn to the stars: what happens when science puts the universe into music by the astronomer, Yaël Nazé.  

The Conversations banner states, Academic rigour, journalistic flair. Apparently, that bit about academic rigour doesn’t apply when an astronomer tries her hand at the history of science. 

The article is actually about sonification, which Ms Nazé turns her attention to rather briefly at the end of her essay. Sonification is a new technique in astronomy of turning satellite astronomical data into sound making the data available to blind people (as this article explains) but possibly revealing other aspects of the data not revealed by visualisation of the data.

There are other explanatory articles, both better than Nazé’s effort, here, and here

However, Ms Nazé thought she could give her essay on the topic a different spin by prefacing her comments on sonification with a look at the historical harmony of the spheres, a topic that should be well known to regular readers of this blog, and it is here that she caused old HULKY such anguish and drove him to distraction. Let us examine her excursion into the chilly waters of the history of science:

Music and astronomy: an ancient love story

Music and space might not seem like natural partners – after all, no air means no sound. But to our forebears, the links were obvious. In Ancient Greece, thinkers such as Aristotle believed the Earth lay at the centre of the universe. This didn’t make it an unchanging ideal, however: to the ancients, terrestrial phenomena were ever-changing, a reflection of our planet’s imperfection. The sky, by contrast, was seen as immutable and eternal, and so worthy of emulation.

Well, it might be true that “no air means no sound”, but our forebears had no idea that there was no air in the heavens. Not just Aristotle, but it was obvious to almost anybody with half a brain that the Earth lies immobile at the centre of the visible heavens. It’s actually very, very difficult to prove otherwise, without a couple of thousand years of evolution of astronomy.  

There is more:

A few of the stars moved with respect to others – so-called “planets” in the etymological sense (for planet means “wandering star”). The ancients knew of seven of them: Mercury, Venus, Mars, Jupiter and Saturn, plus the Sun and the Moon. That number would go on to inform the composition of the days of the week as well as of the music scale.

Planet does not mean “wandering star”, it simply means wanderer. The Greek expression for wandering stars is asteres planetai,” from planasthai “to wander, asteres is of course stars. If you are trying to prove your linguistic sophistication, it pays to get things right. 

The next sentence is simply bullshit. There was an intense discussion on HASTRO_L recently as to where the seven-day week comes from. The answer is we don’t actually know but it certainly predates the astrological week, which gave the weekdays their names based on the planetary hour that begins each day, which seems to be what Ms Nazé is referencing. Ms Nazé obviously doesn’t know very much about music as the seven-tone scale, most commonly used in western music, is only one of numerous music scales with varying numbers of tones. The Pythagorean scale, which is actually from ancient Mesopotamia and falsely attributed to Pythagoras is a twelve-tone scale. Very widespread throughout the world are pentatonic scales with five-tones. The oldest form of Greek music was based on the tetrachord, a scale of just four-tones. I could go one…

On a sidenote although Ms Nazé links to a rather bizarre website about Pythagorean music theory, as error strewn as her own efforts, nowhere in her excurse on harmony of the spheres does she mention the Pythagoreans, who actually invented the concept

Ms Nazé can be very inventive:

Indeed, to the Ancient Greeks, each planet hung on a sphere, which, in turn, revolved around the Earth. Given that movement emitted sound here – such as when two objects rubbed against one another or when feet hit the ground – it made sense that the moving spheres in the cosmos should also produce sounds. 

I have no idea where she got this idea, and although I’ve read quite a lot about the harmony of the spheres, I’ve never come across an explanation remotely like this, so I must assume she simply made it up. Especially, as according to most accounts the music of the spheres could not be heard by normal mortals.

Contrary to those heard on Earth, these were thought to be perfect, prompting the Ancients to use the stars as a template for terrestrial music. [my emphasis]

They didn’t! What the Pythagoreans did was to apply the concept of terrestrial music to the planets.

This is why in the Middle Ages astronomy and music were grouped together in the quadrivium, which also included arithmetic and geometry, and lay the foundations of the liberal arts education.

Astronomy and music, the theory of proportions, were both part of the quadrivium–arithmetic, geometry, music, astronomy­–but arithmetic and music were paired, and geometry and astronomy were paired. Music was arithmetic in motion, and astronomy was geometry in motion. 

But how to weave together notes and planets? This is admittedly the trickiest part. Some scientists have linked a sound’s pitch to a planet’s distance, others with its speed. To add more intricacy to the compositions, at the time perceptions differed in the relative positions of the planets in the solar system.

Of course, the use of the term scientist is totally anachronistic, the people in question are astronomers or philosophers. Once again, I fear that Ms Nazé is simply making things up. I know of no great technical discussion, as to just how the music of the spheres was created. 

The German astronomer Johannes Kepler (1571-1630) was one of the scientists to most notably draw on this Ancient Greek concept of “music of the spheres” (also known as musica universalis) to map out the planetary system. 

She got something right! But it doesn’t last

Kepler’s findings would catapult us into the modern cosmos: he determined that not only was the Sun not at the centre of the solar system – as Nicolaus Copernicus had proposed in the previous century – but also that the planets revolved around it in an elliptical rather than circular motion. 

[“…he determined that not only was the Sun not at the centre of the solar system…” Wow! Some really bad copy editing here. That should, of course, read the Earth. Even corrected it’s not true. Kepler, like everybody else, couldn’t actually deliver proof of the cosmos was heliocentric.]

Addendum 5 February: As can be seen in the comments a debate has developed in the comments about Ms Nazé’s  statement and my interpretation of it, which I now believe to be wrong and have placed in square brackets. I think she is correctly saying that Kepler removed the Sun from the centre of a circle, where Copernicus had placed it and positioned at at one focus of an ellipse. It is actually correct to point out that in Copernicus’ system the Sun is not actually at the centre of the circle but, for mathematical reasons, slightly offset and in reality his system is strictly taken not heliocentric but heliostatic. However, as most people are not actually aware of this, I’m going to be generous and not criticise her for saying that Copernicus had placed the Sun at the centre of the solar system.

As a result, distance and speed changed in the course of the orbit. It became impossible to associate a single note with a single planet, driving him to the conclusion that planets sung melodies.

Here we have something that gets repeated ad nauseum on the Internet. By showing that the planetary orbits were ellipses, Kepler did not show that “distance and speed changed in the course of the orbit.” This had been known for centuries, as could be demonstrated by any good set of ephemerides. What he did, with his elliptical orbits, was to show why this was the case.

The bit about single notes and melodies is once again made up. In his Harmonice Mundi, Kepler investigated every possible arithmetical ratio of all aspects of a planets orbit, looking for harmonic ratios–octave, thirds, fifths etc. Out of these he then constructed melodies for each planet.

Of course, all this had to remain harmonious: for a planet to produce a melody, the highest sound had to chime well with the lowest. Eventually, Kepler abandoned his tunes to concentrate on spelling out his third law on planetary motion in 1619. [my emphasis]

It was at this point, that the HISTSCI_HULK, who had become increasingly agitated as he perused Ms Nazé’s essay. Let out the scream of anguish with which I opened this post.

Let us repeat her sentence:

Eventually, Kepler abandoned his tunes to concentrate on spelling out his third law on planetary motion in 1619.

It would appear that Ms Nazé is not aware of the name of Kepler’s third law or where it originated. The third law is the Harmony Law and is the high point of the Harmonice Mundi! Far from abandoning his tunes, Kepler saw the discovery of his Harmony Law, as validation of his investigations of the harmony of the spheres.