Frequency Atlas

Moon Node Circulation (Cosmic Octave)

234.16 Hz

Nearest note: A♯3, 8 cents above standard tuning

A tone calculated from a measured cycle, by doubling its frequency 37 times. It is calculated, not recorded.

How well is this supported?

DerivedOctave of an astronomical cycle

Calculated from a measured value by a stated method. You can check the arithmetic. What the result means is a matter of interpretation.

The cycle is measured. The tone is calculated from it by doubling, so that it can be heard. Nothing in space makes this sound.

What the four labels meanChecked against sources September 27, 2026

The button plays a plain tone. Start with the volume low. Phone and laptop speakers play low notes quietly; headphones or a speaker help.

Where this number comes from

The orbit of the Moon is tilted against the orbit of the Earth. The two points where they cross drift around the sky once in about 18.6 years. 1 ÷ 586,949,340 seconds, doubled 37 times, is 234.16 Hz. That is a B♭, about 8 cents above standard tuning.

  1. Step 1. Start with the length of the cycle

    Lunar nodes moving through the ecliptic: 6,793 days, 9 hours, 29 minutes.

  2. Step 2. Turn it into a frequency

    One divided by that many seconds is 1.70 × 10⁻⁹ Hz. That is far too slow to hear.

  3. Step 3. Double it 37 times

    Doubling a frequency raises it by one octave: the same note, higher. After 37 doublings it is 234.16 Hz.

  4. Step 4. Name the note

    234.16 Hz is a B♭, 8 cents above standard tuning. A cent is one hundredth of the step between two neighboring piano keys. To play in tune with this tone, an instrument sets its A to 442.03 Hz instead of 440.

  5. Step 5. Keep doubling and the number lands in the range of light

    41 more doublings give the frequency of light with a wavelength of 582 nm, which is yellow. This is arithmetic. It pairs a tone with a color; it does not show that the two are connected.

The method is Hans Cousto’s. Planet gongs explained walks through it and says what it does and does not show.

Facts

Frequency
234.16 Hz
One cycle takes
18.6 years
Wavelength in air (20 °C)
1.46 m
Nearest note
A♯3, 8 cents above standard tuning
Kind of statement
Octave of an astronomical cycle
Filed under
Earth, Moon & Sun

Tuning Data

The row for this tone in Hans Cousto’s tables, with the tempo and pendulum length that follow from it.

Cycle
Lunar nodes moving through the ecliptic
Length of the cycle
6,793 days, 9 hours, 29 minutes
Octaves up
37
Concert pitch (A)
442.03 Hz
Difference from A = 440 Hz
+7.98 cents
Tempo
109.76 beats per minute
Pendulum length
7.4 cm / 2.92 in
Color by octave
Yellow (582 nm)
Tempo and pendulum length, octave by octave
OctaveFrequencyOne cycleTempoPendulum
30tempo1.83 Hz546.63 ms109.76 BPM7.4 cm
313.66 Hz273.32 ms219.53 BPM1.9 cm
327.32 Hz136.66 msToo fast to countToo short to build
3314.64 Hz68.33 msToo fast to countToo short to build
3429.27 Hz34.16 msToo fast to countToo short to build
3558.54 Hz17.08 msToo fast to countToo short to build
36117.08 Hz8.54 msToo fast to countToo short to build
37tone234.16 Hz4.27 msToo fast to countToo short to build
Intervals built on this tone
RatioIntervalFrequencyNoteConcert ACents from 440
1/1Perfect unison234.16 HzA#3442.04 Hz+7.99
81/80Syntonic comma237.09 HzA#3447.56 Hz+29.50
531441/524288Pythagorean comma237.35 HzA#3448.07 Hz+31.45
128/125Diesis239.78 HzA#3452.64 Hz+49.05
648/625Greater diesis242.78 HzB3432.58 Hz-29.45
25/24Chroma243.92 HzB3434.61 Hz-21.34
16/15Diatonic semitone249.77 HzB3445.04 Hz+19.72
10/9Minor whole tone260.18 HzC4437.57 Hz-9.61
9/8Major whole tone263.43 HzC4443.03 Hz+11.90
8/7Septimal whole tone267.61 HzC4450.07 Hz+39.16
6/5Minor third280.99 HzC#4446.05 Hz+23.63
5/4Major third292.70 HzD4438.55 Hz-5.70
4/3Perfect fourth312.21 HzD#4441.54 Hz+6.03
3/2Perfect fifth351.24 HzF4442.53 Hz+9.94
8/5Minor sixth374.66 HzF#4445.54 Hz+21.68
5/3Major sixth390.27 HzG4438.06 Hz-7.65
7/4Natural seventh409.78 HzG#4434.15 Hz-23.18
16/9Pythagorean minor seventh416.28 HzG#4441.04 Hz+4.08
9/5Just minor seventh421.49 HzG#4446.55 Hz+25.59
15/8Major seventh439.05 HzA4439.05 Hz-3.74
2/1Octave468.32 HzA#4442.04 Hz+7.99

Source notes

The lunar nodes are the intersections between the Moon’s orbit and the ecliptic.

Source: Hans Cousto — Tuning Data / Sun Earth Moon Planets. View the source PDF.

License: CC BY-NC-ND 4.0, as stated in Stimmdaten.pdf (German edition), page 2.

Values are reproduced from Cousto’s tables. Tempo, pendulum length and interval tables are calculated by this site from those values.

See every tone in the tables: Open the tuning data reference.

Sources

More about the pitch

The same note in every octave

Each step doubles or halves the frequency. Tap one to hear it.

Entries close in pitch

Within 35 cents of this tone, in any octave. A cent is one hundredth of the step between two neighboring piano keys. Being close in pitch does not mean two things are connected.

Related entries