Starwatch for September 2026

Hello! I’m Karl Hricko of United Astronomy Clubs of NJ and the National Space Society, bringing you the September Starwatch for WNTI –the sound of Centenary.

Who was the astronomer who compared the motion of the planets to the sound of music? It was Johannes Kepler, who is known for his three Laws of Planetary Motion. His idea of connecting the frequency of planet orbits to the frequency of musical pitch was presented in his book called “The Harmony of the World”, which was written in 1619. It was the idea of Converting planet speeds into musical tones. Tone is the color or timbre of a pitch, and pitch is the quality of a sound governed by the frequency of vibration producing it. It was an outgrowth of Kepler’s Third Law of Planetary Motion. In it he stated that a planet’s orbital period (its year) is proportional to its distance from the Sun,

Kepler believed that each planet emits atone that varies in pitch as its distance from the Sun varies from its near point to its far point in orbit. Together, the planets produce the Music of the Spheres. Mercury is the soprano, Venus and Earth are altos, Mars is the tenor, and Jupiter and Saturn are Basses.

This idea never gained widespread support. Yet, harmonic relations are known today to be crucial, through the mechanism of dynamic resonance – the vibration of one object causing a vibration in a second object,, at the same frequency. This is of central importance in our current understanding of the motions of planets and moons in our solar system.

In their harmonious frequencies, after sunset you can see Venus above Mercury

In the west – both in Virgo. If you look to the east, Saturn appears in Pisces. Before sunrise, Mars can be seen to the east in Gemini, while below it we can spot Jupiter in Cancer. The Autumnal Equinox begins on Tuesday the 22^nd at 8:04 P.M. EDT.

s you look up at the heavens, this month, you may not hear the music of the spheres, but you will see the rhythm of the planets.

Until our next Starwatch –     Don’t forget To check out     What’s up in the Night sky!