Frequency Atlas

Mars Orbit (Cosmic Octave)

144.72 Hz

Nearest note: D3, 25 cents below standard tuning

A tone calculated from a measured cycle, by doubling its frequency 33 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

Mars goes around the Sun in 686.98 days, about 1.88 Earth years. 1 ÷ 59,355,072 seconds, doubled 33 times, is 144.72 Hz. That is a D, about 25 cents below standard tuning.

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

    Mars orbit around the Sun: 686.98 days.

  2. Step 2. Turn it into a frequency

    One divided by that many seconds is 1.68 × 10⁻⁸ Hz. That is far too slow to hear.

  3. Step 3. Double it 33 times

    Doubling a frequency raises it by one octave: the same note, higher. After 33 doublings it is 144.72 Hz.

  4. Step 4. Name the note

    144.72 Hz is a D, 25 cents below 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 433.67 Hz instead of 440.

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

    42 more doublings give the frequency of light with a wavelength of 471 nm, which is blue. 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
144.72 Hz
One cycle takes
686.98 days
Wavelength in air (20 °C)
2.37 m
Nearest note
D3, 25 cents below standard tuning
Kind of statement
Octave of an astronomical cycle
Filed under
Planets

Tuning Data

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

Cycle
Mars orbit around the Sun
Length of the cycle
686.98 days
Octaves up
33
Concert pitch (A)
433.67 Hz
Difference from A = 440 Hz
-25.07 cents
Tempo
67.84 beats per minute
Pendulum length
19.4 cm / 7.65 in
Color by octave
Blue (471 nm)
Tempo and pendulum length, octave by octave
OctaveFrequencyOne cycleTempoPendulum
26tempo1.13 Hz884.47 ms67.84 BPM19.4 cm
272.26 Hz442.23 ms135.68 BPM4.9 cm
284.52 Hz221.12 ms271.35 BPM1.2 cm
299.05 Hz110.56 msToo fast to countToo short to build
3018.09 Hz55.28 msToo fast to countToo short to build
3136.18 Hz27.64 msToo fast to countToo short to build
3272.36 Hz13.82 msToo fast to countToo short to build
33tone144.72 Hz6.91 msToo fast to countToo short to build
Intervals built on this tone
RatioIntervalFrequencyNoteConcert ACents from 440
1/1Perfect unison144.72 HzD3433.67 Hz-25.09
81/80Syntonic comma146.53 HzD3439.09 Hz-3.58
531441/524288Pythagorean comma146.69 HzD3439.59 Hz-1.63
128/125Diesis148.19 HzD3444.08 Hz+15.97
648/625Greater diesis150.05 HzD3449.63 Hz+37.48
25/24Chroma150.75 HzD3451.74 Hz+45.59
16/15Diatonic semitone154.37 HzD#3436.62 Hz-13.36
10/9Minor whole tone160.80 HzE3429.28 Hz-42.68
9/8Major whole tone162.81 HzE3434.65 Hz-21.18
8/7Septimal whole tone165.39 HzE3441.55 Hz+6.09
6/5Minor third173.66 HzF3437.61 Hz-9.45
5/4Major third180.90 HzF#3430.26 Hz-38.77
4/3Perfect fourth192.96 HzG3433.18 Hz-27.04
3/2Perfect fifth217.08 HzA3434.16 Hz-23.13
8/5Minor sixth231.55 HzA#3437.11 Hz-11.40
5/3Major sixth241.20 HzB3429.77 Hz-40.73
7/4Natural seventh253.26 HzB3451.26 Hz+43.74
16/9Pythagorean minor seventh257.28 HzC4432.69 Hz-29
9/5Just minor seventh260.50 HzC4438.10 Hz-7.49
15/8Major seventh271.35 HzC#4430.74 Hz-36.82
2/1Octave289.44 HzD4433.67 Hz-25.09

Source notes

The Mars tone is based on the planet’s sidereal year rather than a synodic Earth-relative cycle.

Source: Hans Cousto — Tuning Data / Sun Earth Moon Planets. View the source PDF, page 29.

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.

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