Schumann resonance: what 7.83 Hz really is

What is the Schumann resonance?

Lightning flashes somewhere on Earth about 44 to 50 times a second, by NASA's satellite count and a review by Colin Price. Every flash sends out radio waves, some of them at extremely low frequencies: a few cycles a second up to a few dozen. The ground conducts electricity and so does the ionosphere, the charged layer of the upper atmosphere, so these slow waves are trapped in the gap between the two and travel right round the planet.

A radio wave at 7.8 Hz is about 38,400 kilometres long, close to the Earth's circumference of about 40,000 kilometres. When a whole number of wavelengths fits the trip round the globe, waves arriving from both directions meet in step and build up, the way a note builds in an organ pipe. NASA describes the condition in those terms, and those reinforced frequencies are the Schumann resonances. Its scientists give the average measured values of the five lowest as about 7.8, 14.3, 20.8, 27.3 and 33.8 Hz.

The signal is faint. Its magnetic part is a few picotesla, roughly a million times weaker than the Earth's own magnetic field at the surface. Recording it takes sensitive induction coils in an electrically quiet place, like the pair the British Geological Survey runs at Eskdalemuir in southern Scotland. Here is one day of their data.

Strength at each frequency, in pT per √Hz10203040Frequency in Hz, 3 to 45. The dashed lines mark NASA’s five average values.

Eskdalemuir's peaks that day, in hertz, beside NASA's averages and the ideal cavity

Mode	That day	NASA	Ideal
1	7.77	7.8	10.6
2	13.87	14.3	18.3
3	19.76	20.8	25.9
4	26.67	27.3	33.5
5	31.65	33.8	41.0

Download the day's spectrum (CSV)

Why is it lower than the theory predicts?

Because the real cavity leaks. The formula for an ideal shell with perfectly conducting walls puts the five lowest resonances at about 10.6, 18.3, 25.9, 33.5 and 41.0 Hz, and a 1965 survey of the field set the first four beside measured values of 8, 14.1, 20.3 and 26.4 Hz. The ionosphere conducts imperfectly, so the waves lose energy as they go and the peaks settle lower and broader than in the ideal case, at about three quarters to four fifths of the ideal values.

The cavity is also thin. Its roof is the lower edge of the ionosphere, which NASA puts at about 60 miles up, roughly 97 kilometres. By day the Sun charges a lower layer, the D region at 50 to 90 kilometres, so the roof drops; NASA's paper notes that it is lower during the day.

The Earth's radius6,371 km Height of the cavity's roofabout 97 km

The cavity to scale

Distance	Kilometres
The Earth's radius	6,371 km
Height of the cavity's roof	about 97 km

Who discovered the Schumann resonance?

The idea is older than the name. Price traces it to the Irish physicist George FitzGerald in 1893 and to Nikola Tesla in 1905. Tesla's patent of that year pictured the Earth itself thrown into resonance "just like a wire", and guessed that "the lowest frequency would appear to be six per second", though his waves ran through the ground rather than between the ground and the sky.

The name belongs to Winfried Otto Schumann, a German physicist. In 1952 he worked out that the shell of air between the ground and the ionosphere must have natural frequencies, that a sudden jolt such as a lightning flash would set them off, and that the lowest would sit near 11 cycles a second. His first attempt to measure them, with Herbert König, failed. König found the first experimental signs in the late 1950s, and Balser and Wagner published the first detailed spectra in Nature in 1960, as the 1965 survey records.

It has been watched from the ground ever since, and even from orbit: a NASA instrument on the C/NOFS satellite picked it up from space for the first time, a sign that some of its energy leaks beyond the atmosphere. It has also become a working tool. Lightning grows much more frequent as the tropics warm, so the strength of the resonance tracks their temperature; a 1992 study in Science proposed it as a tropical thermometer.

Is 7.83 Hz the Earth's frequency?

Not in the sense of the planet vibrating. The Schumann resonance belongs to the gap between the ground and the ionosphere, not to the rock, and its number is not fixed: 7.83 Hz is one rounded value for a peak that moves by tenths of a hertz with the hour, the season and the Sun. The name "the heartbeat of the planet" comes, as a Hungarian geophysics institute puts it, from esoteric circles; the institute calls it, more accurately, a natural, low-frequency electromagnetic hum.

Other numbers get called the Earth's frequency too. Hans Cousto's cosmic octave takes the length of the Earth's day and of its year and raises them, octave by octave, into hearing range, giving 194.18 Hz for the day and 136.10 Hz for the year. Those are tones made by arithmetic from the Earth's motion; the Schumann resonance is a measured electromagnetic signal. The guide to planetary frequencies explains Cousto's method.

What is the Schumann frequency doing right now?

Drifting a little, as it always does. The first peak moves with the time of day, the season and the Sun's eleven-year cycle, by tenths of a hertz rather than whole hertz.

• Through the day. At the University of Granada's station in the Sierra Nevada, the first peak in the north-south sensor tops out around 08:00 and 20:00 UTC and dips in the early hours and again around 15:00, in the station's four-year study.
• Through the year. At Eskdalemuir it runs above 8 Hz in winter and below 7.9 Hz in summer.
• Over the solar cycle. At Modra Observatory in Slovakia the yearly mean was 7.85 Hz near a solar maximum and 7.55 Hz in a deep minimum.
• In a solar storm. A strong solar flare raised it by about 0.3 Hz at a station in Rhode Island, and the stream of protons that followed lowered one component there by about 0.8 Hz.

First peak, hourly mean: 7.61 to 7.98 Hz00:0006:0012:0018:0024:00Time of day, UTC. The plot runs from 7.3 Hz at its foot to 8.3 Hz at its top; the dashed line marks 7.83 Hz.

The first peak through an average day, Sierra Nevada, one spring month

Hour (UTC)	Mean first peak
01:00	7.62 Hz
08:00	7.98 Hz
15:00	7.61 Hz
19:00	7.86 Hz

Download all 24 hours (CSV)

Its strength follows the world's thunderstorms. The British Geological Survey notes that the resonance is weaker through the UK night, while the Sun is over the Pacific and few storms are firing, and grows stronger later in the day once the heat over equatorial land such as Africa sets storms off. It posts spectrograms of the previous day from its two Eskdalemuir coils on its induction coil page, open to anyone.

What causes Schumann resonance spikes?

Usually something nearby, not the planet. A spectrogram shows strength at each frequency over time. On one, the Schumann resonances are soft bands that are always there, while the sudden bright stripes across every frequency are, in the British Geological Survey's words, "due to local lightning activity or short system errors". Thin, steady lines are usually man-made: the survey's example chart carries one at 25 Hz, which it traces to the UK's electrical power system, and the day of data drawn above carried narrow lines at 25, 30, 35, 40 and 45 Hz.

So a spike on one of these charts usually records something local, a nearby storm or a glitch, not the Earth's frequency jumping. The peaks themselves move by tenths of a hertz, and even the solar storm above shifted the first one by less than one.

What does the Schumann resonance do to humans?

No effect on people has been established. The studies are few and small, most are correlations, and none of the peer-reviewed ones played a sound. Here is what they actually looked at.

• Cardiovascular readings. One study followed 56 adults for a week and found lower average arterial pressure on days the authors classed as enhanced Schumann days. Nothing was given to anyone; it is a correlation.
• Brain recordings. Saroka and colleagues looked back over the EEG records of 184 people and saw peaks near the first three Schumann frequencies in averaged brain activity "in some but not all participants", and they note that third factors may affect both.
• Body clocks in a bunker. In Wever's bunker studies, volunteers lived in a room shielded from natural fields, and a weak 10 Hz electric field shortened their free-running daily rhythm, as the natural fields did. That was 10 Hz, an electric field and a bunker, not a 7.83 Hz sound.
• Magnetic fields at the Schumann frequency. Two small studies exposed people to weak magnetic fields: six men at the wrist, with no sham comparison, and 20 teenage boys, to test their jumping. Neither involved sound.
• Hypotheses and reviews. Cherry proposed the resonance as the link between solar activity and health, through melatonin, and a 2025 narrative review states that human brainwave activity is "highly dependent" on it. Neither adds new measurements.
• Spaceflight. A white paper hosted on NASA's science site suggests the absence of the resonance beyond low Earth orbit "may pose a risk to astronauts" and proposes ground studies. It was written for an open call for community papers; it is not a NASA finding and reports no measurements of its own.

None of these exposed anyone to a sound. A PubMed search pairing Schumann with binaural beats returns nothing, and the only test of a 7.83 Hz sound in people that turned up is a 2017 doctoral thesis on isochronic tones, not a peer-reviewed paper.

Does the Schumann resonance affect sleep?

There is no good evidence that it does. The one placebo-controlled trial randomly gave 46 adults who slept poorly a bedside "Schumann resonance" device or an identical-looking placebo that gave out nothing, for four weeks, and 40 finished. On its main measure, overnight sleep recordings, the two groups did not differ significantly; the nearest result, the time it took to drop off, had p = 0.055.

The paper describes the device's output only as a "Schumann resonance frequency (7.83 Hz) wave, theta wave, and delta wave", without saying whether that means a field, a sound or something else. The device's patent licence belongs to one of the authors, and the trial was registered after it had started, with a different main measure from the one the paper reports. A second trial of the device, in 35 people who wake in the night needing the toilet, had no placebo and no objective sleep measure. Wever's bunker work concerns body clocks, not sleep quality.

Can you hear the Schumann resonance?

No. It is an electromagnetic wave, and ears respond to pressure waves in air. A sound at 7.83 Hz would be infrasound, below ordinary hearing. Hearing research puts the threshold down there near 100 decibels: a standard review's curve lies close to 97 decibels, G-weighted, and Bavaria's state environment agency gives 103 decibels at 8 Hz, which it compares to a jackhammer right next to you.

That is why our 7.83 Hz is a binaural beat, not a 7.83 Hz tone.

What is a 7.83 Hz binaural beat?

Two steady tones, one in each ear, 7.83 Hz apart. On Harmonance the left ear hears 108 Hz and the right ear 115.83 Hz. Neither ear receives anything at 7.83 Hz. The beat, a slow pulse 7.83 times a second, forms in the brainstem, where the signals from the two ears meet, which is why it needs headphones: through speakers both tones reach both ears and mix in the air. Gerald Oster described these "auditory beats in the brain" in 1973.

Left ear: 108 HzRight ear: 115.83 HzThe beat between them: 7.83 Hz

The two tones of the 7.83 Hz binaural beat

Ear	Tone
Left ear	108 Hz
Right ear	115.83 Hz

We measured it to be sure. One minute from the middle of the approved nine-hour master behind our 7.83 Hz video, rebuilt from the same recipe and code that wrote it, holds one tone in each ear and nothing at 7.83 Hz: the level there is more than 160 decibels below the tones, beneath the noise floor of 24-bit audio. The 7.83 Hz appears only in the loudness of the two tones mixed together, which rises and falls 7.83 times a second.

Left ear: one tone, 108.00 HzRight ear: one tone, 115.83 Hz7.8350100130Frequency in Hz, 0 to 130, drawn from 120 dB below full scale. The dashed line marks 7.83 Hz.

What each ear of the master holds, in decibels below full scale

Where	Strongest tone	Its level	At 7.83 Hz
Left ear	108.00 Hz	21.4 dB	224 dB
Right ear	115.83 Hz	21.5 dB	185 dB
Both ears mixed	108.00 Hz	27.4 dB	191 dB

Download both ears (CSV)

What a binaural beat does is a separate, open question. A meta-analysis of 22 studies found a medium overall effect on measures such as memory and attention. A systematic review of 14 EEG studies found that five supported the idea that the brain falls into step with the beat, eight contradicted it and one was mixed. No published study of a 7.83 Hz binaural beat in particular turned up in this research. The guides to theta waves, brainwave bands and isochronic tones against binaural beats go further.

How do you listen to the 7.83 Hz binaural beat?

Put on headphones, keep the volume low and press play at the top of this page, or open the 7.83 Hz Schumann resonance page to keep it going while you read, work or rest. 7.83 Hz sits at the top of the theta band, so the 6 Hz theta beat is a close neighbour, and the whole set is in the binaural beats collection. To start from how you feel instead, want to feel grounded? gathers tones traditionally tied to feeling steady.

Sources and limits

Every outside source below was opened and checked for this guide. Some things could not be checked: the full texts of Balser and Wagner's 1960 paper and of König's papers, which are not free to read, and the full text of the one doctoral thesis on a 7.83 Hz sound. The ideal-cavity values and the scale of the cavity are our own arithmetic from NASA's Earth radius. The station charts show one day and one month at two places, so read their exact values as snapshots of a signal that keeps moving.

1. Simões and colleagues, NASA Goddard: the measured modes, the ideal formula and the lower daytime roof.
2. NASA Technical Reports Server: the resonance condition and its detection from space.
3. NASA Scientific Visualization Studio: the cavity's roof and the energy that leaks out.
4. Christian and colleagues, NASA: 44 lightning flashes a second.
5. NASA Earth fact sheet: the Earth's mean radius.
6. Price, Atmosphere: the review of the Schumann resonance, its history and its uses.
7. Schumann, Zeitschrift für Naturforschung: the 1952 prediction.
8. Galejs, Journal of Research of the NBS: the early measurements against the ideal cavity.
9. Balser and Wagner, Nature: the first detailed spectra.
10. Tesla, US patent 787,412: six cycles a second through the ground.
11. Williams, Science: the resonance as a tropical thermometer.
12. NOAA Space Weather Prediction Center: the height of the D region.
13. British Geological Survey, induction coils: what spikes on a spectrogram are, and the daily cycle.
14. British Geological Survey, Eskdalemuir coil data: the data behind the first chart.
15. Salinas and colleagues, University of Granada: the Sierra Nevada station and the strength of the field.
16. University of Granada, Sierra Nevada station data: the data behind the second chart.
17. Rodríguez-Camacho and colleagues, JGR Atmospheres: the daily rhythm of the first peak.
18. Musur and Beggan, Sun and Geosphere: the seasons at Eskdalemuir.
19. Ondrášková and colleagues, Contributions to Geophysics and Geodesy: the solar cycle at Modra.
20. Sátori and colleagues, Surveys in Geophysics: the flare and the proton storm.
21. HUN-REN Institute of Earth Physics and Space Science: where "the heartbeat of the planet" comes from.
22. Mitsutake and colleagues: the week of cardiovascular readings.
23. Saroka and colleagues, PLOS ONE: the EEG records.
24. Wever: the bunker and the 10 Hz field.
25. Mayrovitz and Danho and colleagues: the magnetic-field studies.
26. Cherry, Natural Hazards and Nelson, Electromagnetic Biology and Medicine: the hypothesis and the review.
27. Stolc and colleagues, white paper and the National Academies' call: the spaceflight proposal.
28. Ray, doctoral thesis: isochronic tones at the Schumann frequency.
29. Huang and colleagues, Nature and Science of Sleep, its trial registration and Chen and colleagues, Medicine: the sleep device.
30. Møller and Pedersen, Noise and Health and the Bavarian State Office for the Environment: hearing below 20 Hz.
31. Oster, Scientific American, Ingendoh and colleagues, PLOS ONE and Garcia-Argibay and colleagues: binaural beats and what is known about them.