Cosmic Cycles
Schumann Resonance (3rd harmonic)
20.80 Hz
Cosmic Octave Color
Derived visible color (410 nm)
Display swatch #8a4deb
EstablishedAstronomical Mapping
Evidence Level
Established
Source Count
1
Last Reviewed
March 23, 2026
Directly measured, standardized, or well-supported in mainstream scientific or technical literature.
The underlying cycle is measurable, but the audible tone is an octave-transposed mapping used for comparison, listening, and practice rather than a naturally audible emission.
Review the evidence modelThird mode of Schumann resonance.
Wavelength
16.49 m
Nearest Note
E0 (+17¢)
Claim Type
Astronomical Mapping
Cosmic Octave Color
Derived visible color (410 nm) · #8a4deb
Source
Geophysics
Sources
Geophysics and Schumann Resonance Literature
4 atlas references
Used for atmospheric resonances, Earth-ionosphere cavity behavior, and related geophysical frequencies.
W.O. Schumann (1952) and later geophysical literature.
Octave Ladder
Every audible octave of this frequency — the same tone, higher and lower.
Nearby in the Atlas
Entries within ±35 cents of this tone when reduced to the same octave — candidates for pairing or comparison.
E2Musical Frequencies
82.41 Hz-16.5¢
E3Musical Frequencies
164.81 Hz-16.6¢
E4Musical Frequencies
329.63 Hz-16.6¢
E5Musical Frequencies
659.26 Hz-16.6¢
E6Musical Frequencies
1.3 kHz-16.6¢
E7Musical Frequencies
2.6 kHz-16.6¢
schumannharmonic