Discover how geoneutrinos are reshaping our understanding of Earth’s heat sources and the dynamic nature of its interior.
J.Konstapel,Leiden,4-10-2026.
Based on an article in Wired today named “‘Geoneutrinos’ Are Building a New Map of Earth’s Volatile Interior
Introduction
The Earth is warm, and it should not be. A planet of this age, left alone, would have cooled long ago. It has not. Part of the answer lies in the rock itself. Uranium, thorium, and potassium decay in the mantle and the crust. That decay releases heat. It is one of the two engines of the planet’s interior. The other is the residual heat of its formation.
For a long time, this interior heat was a matter of models and estimates. That changed in 2005. A detector in Japan caught the first geoneutrinos. These are particles born in the radioactive decay inside the Earth. They pass through the planet almost undisturbed. A tiny fraction reaches the surface. Detectors built for other purposes can count them.
In August 2026, Quanta Magazine published a report on this field. Wired reprinted it in October. The report describes three detectors on three continents. It records a puzzling result: the three sites measure three different values. A fourth detector, in southern China, is expected to publish its first result later this year.
This essay does four things. First, it summarises the report and its facts. Second, it introduces the ladder of three: a scale model in which every size and duration occupies a numbered layer. Third, it places the Earth’s heat sources on that ladder and reads what the ladder says about the Chinese measurement, in advance of that measurement. Fourth, it draws out what this means for the people who live on top of that heat.
1. The report: what the detectors saw
Geoneutrinos are produced when uranium, thorium, and potassium decay. They are a direct signal from the planet’s interior. They carry information that no drill can reach. The deepest borehole penetrates about twelve kilometres. The detectors, in effect, look through almost three thousand kilometres of rock.
The report assembles the following facts.
- Japan, 2005. The KamLAND detector caught the first geoneutrinos. Detection has always been slow work.
- Italy, 2009–2010. The Borexino detector followed. It reports the highest signal of the three sites.
- Canada, November 2025. The SNO+ detector, two kilometres underground near Sudbury, reported its first catch. It added roughly fifty geoneutrinos. It is the first site in the western hemisphere.
- In total, only a few hundred geoneutrinos have ever been detected.
- The three sites disagree. The mantle signal is high in Italy, low in Japan, and in between in Canada.
- The strongest sources appear to lie above two continent-sized blocks of hot, dense rock at the bottom of the mantle. One block lies under Africa. The other lies under the Pacific.
- The uncertainty is large. Radioactive decay may supply a few percent of the mantle’s heat, or half of it.
- A fourth detector, in southern China, has been running since August 2025. It holds more than 20,000 tons of liquid. It is expected to catch more geoneutrinos in one year than the three existing sites caught in decades.
The disagreement matters. Geochemists have long assumed that the mantle is well mixed. Three different values from three detectors hint that it is not. The interior of the planet may be as varied as its surface.
2. The ladder of three
To read these facts in context, this essay uses the ladder of three from the Vacuum.Net. The image behind it is a fishnet in water. Every strand stands under tension. Where strands wind around each other, knots appear. A winding persists only when it returns in phase.
The net describes every place as a depth plus a number. That number uses three signs: +1, 0, and −1. One sign is called a trit. Each step on the ladder is a factor of three in scale. One trit more means one layer deeper.
The measuring rod of the net is a natural unit:
- Length: $S_0 = 45.6$ nm.
- Time: $T_0 = 1.521 \times 10^{-16}$ s.
Layer n has the length $3^n \cdot S_0$ and the time $3^n \cdot T_0$. To find the layer of any size, ask how many factors of three separate it from the measuring rod. That number is its position. The nearest whole number is its layer.
Two examples make the method clear. A human body of 1.8 metres lies at position 15.9, so on layer 16. The year lies at position 48.9, so on layer 49.
The advantage of the ladder is compactness. From the proton to the observable universe, the ladder runs from layer −16 to layer 71. Eighty-eight layers cover everything physical.
3. Layers below zero
The geoneutrino is far smaller than the measuring rod, so its layer number is negative. This raises a fair question. Many readers know a scale with an absolute floor: zero kelvin. Is a negative layer a smaller-than-nothing quantity?
It is not. A layer number is not an amount. It is a count of steps. Layer 0 is a measuring rod, not a floor. It is chosen the way the metre is chosen.
| Measure | Power of ten | What it is |
|---|---|---|
| Kilometre | 3 | a thousand metres |
| Metre | 0 | the measuring rod |
| Millimetre | −3 | a thousandth of a metre |
| Nanometre | −9 | a billionth of a metre |
A millimetre is not a negative length. The ladder works the same way, with steps of three instead of ten.
The absolute floor still exists. It is size zero. On a ladder of steps it is never reached, because every step down leaves one third. The floor lies at layer minus infinity.
The following table fixes the scale.
| Layer | Size | What lies there | Position |
|---|---|---|---|
| 16 | 1.96 m | The human body | 15.9 |
| 0 | 45.6 nm | The measuring rod; a small virus | 0 |
| −2 | 5.07 nm | Cell membrane (5 nm) | −2.01 |
| −3 | 1.69 nm | Strand of DNA (2 nm) | −2.85 |
| −6 | 62.6 pm | Hydrogen atom (radius 52.9 pm) | −6.15 |
| −9 | 2.32 pm | Wavelength of the electron (2.43 pm) | −8.96 |
| −10 | 0.77 pm | Geoneutrino of 2 MeV (0.62 pm) | −10.20 |
| −14 | 9.5 fm | Nucleus of uranium (7.4 fm) | −14.23 |
| −16 | 1.06 fm | Proton (radius 0.84 fm) | −16.21 |
4. The three families
The ladder has one rule for neighbours. Three neighbouring trits form a window. The window is closed when the three signs add to zero, counted modulo 3.
Applied across three neighbouring layers, the rule has a strong consequence. If window n closes and window n+1 closes:
- $T(n-1) + T(n) + T(n+1) = 0$
- $T(n) + T(n+1) + T(n+2) = 0$
- Subtracting gives $T(n+2) = T(n-1)$.
In a closed chain, every third layer carries the same state. The layers fall into three families:
- Family A: layer numbers 1, 4, 7, … and −2, −5, …
- Family B: layer numbers 2, 5, 8, … and −1, −4, …
- Family C: layer numbers 0, 3, 6, … and −3, −6, …
Two families are free. The third follows from them: $C = -(A + B)$. This closure rule is the working tool of the rest of this essay.
5. The heat sources on the ladder
Each heat source keeps its own clock: the half-life. This is the time in which half of the source has decayed.
| Source | Half-life | Position | Layer | Family |
|---|---|---|---|---|
| Potassium-40 | 1.248 billion years | 67.93 | 68 | B |
| Uranium-238 | 4.468 billion years | 69.10 | 69 | C |
| Thorium-232 | 14.05 billion years | 70.14 | 70 | A |
The calculation for uranium shows the method. Its half-life of 4.468 billion years is $1.410 \times 10^{17}$ seconds. Divided by $T_0$, that is $9.27 \times 10^{32}$. The logarithm to base three of that number is 69.10.
Three results follow.
First, the three sources lie on three neighbouring layers. Each lies within 0.14 of a layer of its whole number. Together they form exactly one window, with one member from each family. This is a striking regularity. The three clocks of the planet’s heat are not scattered across the ladder. They sit side by side.
Second, two of them share their layer with an age. The Earth is 4.54 billion years old, position 69.11 — beside uranium at 69.10. The universe is 13.8 billion years old, position 70.12 — beside thorium at 70.14. The clock of uranium is, in effect, the clock of the planet. The clock of thorium is the clock of the universe.
Third, it is the last window before the edge. Layer 71 is the radius of the observable universe. The heat of the Earth runs on the three slowest clocks the ladder has.
6. What is measured and what is not
The detectors catch a geoneutrino through one reaction. That reaction requires 1.8 MeV of energy. The geoneutrinos of uranium and thorium reach that threshold. Those of potassium stop at 1.3 MeV. Potassium is therefore invisible to every detector now in use.
In ladder terms: layers 69 and 70 are measured. Layer 68 is not. The unmeasured layer is the one in family B.
The closure rule fills that gap. With two neighbours known, the third is fixed:
$$T(68) = -(T(69) + T(70))$$
The state of the potassium layer follows from the two measured layers. This is the practical value of the family structure. A missing measurement does not leave a hole. It leaves a dependent quantity, waiting for its two neighbours to be measured well.
7. Where it lies inside the Earth
The ladder also orders the interior of the planet itself.
| What | Size | Position | Layer | Family |
|---|---|---|---|---|
| Detector underground | 2 km | 22.30 | 22 | A |
| Continental crust | 35 km | 24.91 | 25 | A |
| Nearby crust that disturbs the signal | 300 km | 26.87 | 27 | C |
| Height of the two blocks | about 1,000 km | 27.96 | 28 | A |
| Inner core | radius 1,220 km | 28.14 | 28 | A |
| Mantle | 2,890 km thick | 28.93 | 29 | B |
| Outer core | radius 3,480 km | 29.10 | 29 | B |
The two blocks under Africa and the Pacific have the size of layer 28. That is the layer — and the family — of the inner core. The mantle and the outer core lie together on layer 29, in family B.
The central question of the report is whether the mantle is uniform. On the ladder, that question reads: does layer 29 carry one state, or does something of layer 28 lie inside it? The seismologists have already given their answer. Something of layer 28 lies inside layer 29, on two sides of the core. The geoneutrino data point at the same structures.
There is a further symmetry worth noting. The geoneutrino itself lies on layer −10, in family B. That is the family of the mantle it comes from — and of the potassium layer it cannot show.
8. Three sites, three states
The three sites report high, low, and in between. Those are precisely the three states of a trit.
| Site | Mantle signal | State |
|---|---|---|
| Italy | high | +1 |
| Canada | in between | 0 |
| Japan | low | −1 |
The sum is zero. The three sites form a closed window of the kind that holds all three values.
On this reading, the difference between the sites is not an error to be removed. It is the form in which a closed window shows itself. This is a matter of interpretation, and it should be stated plainly: the researchers say the uncertainty is still too large to tell the sites apart with confidence. The reading above takes their best estimates as they stand.
9. The measurement from China
The fourth detector reports later this year. What the ladder says is recorded here, on 4 October 2026, before the result is known. This is a prediction, made in advance.
- A trit has three states. A fourth site adds no fourth value. It repeats one of the three.
- The detector stands in Asia, on the same side of the Earth as Japan. On this reading it repeats the state of Japan: low.
- With enough counts, the detector can separate uranium from thorium. Those are layers 69 and 70. Their two states fix the state of layer 68 — potassium — which no detector sees.
The first two lines will be settled by the first report of the collaboration. The third will be settled only when a detector for potassium exists. The report mentions one more plan: a detector on the ocean floor, far from the continental crust. It would read the mantle alone — layer 29 without the crustal layers 25 and 27.
10. What it means for people
People live on layers 16 to 22. That is the body, the house, the village, and the first kilometre of air. Under them, the planet is kept warm by three clocks that tick on the scale of the Earth and the universe.
That heat is not a detail. It moves the mantle. The moving mantle shifts the continents and renews the ground. The moving outer core generates the magnetic field. The field keeps the atmosphere from being stripped away by the solar wind. Without that heat, the Earth would have cooled long ago into a dead planet. Everything that lives, lives on top of it.
Four observations follow.
The ground is not still. It is the surface of a heat engine that has run for 4.5 billion years. Of its uranium, almost exactly half is left: 49 percent. The engine is at mid-life — and so, in that sense, is the planet.
This is the given side. No one sets the state of layers 68 to 70, or of the core. In the family structure, these belong with orbit, axis, and Sun. What people can set lies elsewhere: the water on their own land, the surface, the thin layer of choice. Knowing which side is given is the beginning of acting on the other.
It is a shared reading. Four detectors on three continents, built by people from many countries, count a few hundred particles to learn what lies under everyone’s feet. No country owns the mantle. The map that results belongs to all.
The same clocks serve as fuel. Uranium and thorium are the elements people mine for nuclear power. A reactor draws on the same decay that warms the planet from within. The detectors must subtract the reactor signal to see the Earth. Human use and planetary source are one process at two depths.
Conclusion
The report from Quanta and Wired describes a field in transition. After decades of single-digit annual counts, a detector arrives that changes the rate of data collection by an order of magnitude. The question is no longer whether geoneutrinos can be counted, but what the counts mean.
The ladder of three offers one way to organise the answer. It places the three heat sources on three neighbouring layers, 68, 69, and 70 — the last window before the edge of the observable universe. It binds them into one structure through the closure rule, so that the unmeasured source, potassium, becomes a dependent quantity rather than a blank. It reads the three disagreeing sites as a closed window: three states, summing to zero. And it commits, in advance, to a prediction for the Chinese detector: a low value, repeating Japan.
These readings may change. The uncertainty in the field remains large, and a new measurement may overturn any interpretation. That is precisely why the prediction is recorded before the fact. On this point the essay is explicit: this is the reading of 4 October 2026. The China result, when it arrives, will tell us whether the ladder saw correctly.
Status of the claims
- From the report. The three sites and their values; the two blocks; the fourth detector and its date.
- Derived. The three families from the closure rule; the positions of the half-lives, the ages, and the sizes.
- Read from the ladder. The three sites as one closed window; the two blocks as layer 28 inside layer 29; the potassium layer as the dependent one.
- Recorded in advance. The three lines on the measurement from China.
- Open. The states of layers 68 to 70; the families below layer 0; a detector for potassium.
Annotated references
Dinneen, J. (2026). “Neutrinos From Deep Inside Earth Provide a New Picture of the Mantle.” Quanta Magazine, 7 August 2026. Reprinted in Wired, October 2026, as “Elusive Geoneutrinos Are Building a New Map of Earth’s Volatile Interior.”
Why read? This is the occasion of the essay. It gives the three sites, their different values, the two blocks at the base of the mantle, and the fourth detector in China. It is the most accessible single account of the current state of the field. Reading advice: the map of the detectors and the passage on the uncertainty; together they show both the promise and the limits of the data.
Konstapel, J. (2026). The Climate on the Ladder of Three. Constable Research, Leiden, 3 October 2026.
Why read? The full derivation of the layers, the inventory of what lies on layers 0 to 71, and the three families applied to the climate. It is the technical foundation for the ladder used throughout this essay. Reading advice: Sections 3 and 6, and Appendix A; a reader who works through those can reproduce every number cited here.
Araki, T., and others (KamLAND Collaboration) (2005). “Experimental investigation of geologically produced antineutrinos with KamLAND.” Nature 436, 499–503.
Why read? The first detection, in Japan. It shows how few particles carry the whole argument, and how a detector built for reactor neutrinos was turned into a probe of the planet’s interior.
Bellini, G., and others (Borexino Collaboration) (2010). “Observation of geo-neutrinos.” Physics Letters B 687, 299–304.
Why read? The second site, in Italy, with the high value. Comparing it with KamLAND is the clearest way to see why the field began to suspect that the mantle is not uniform.
SNO+ Collaboration (2025). “First measurement of geoneutrinos at SNO+.” arXiv:2511.11856.
Why read? The third site, in Canada, and the first in the western hemisphere. It is the measurement that made three values out of two, and it is the immediate cause of the current debate.
An, F., and others (JUNO Collaboration) (2016). “Neutrino physics with JUNO.” Journal of Physics G 43, 030401.
Why read? The design of the detector in China and what it expects to see. Reading advice: the chapter on geoneutrinos; it explains why this detector can collect in one year what earlier detectors collected in decades.
Šrámek, O., and others (2016). “Revealing the Earth’s mantle from the tallest mountains using the Jinping Neutrino Experiment.” Scientific Reports 6, 33034.
Why read? The expected counts per site — about 400 a year in southern China — and how several sites together narrow the estimate of the mantle’s heat. Useful for judging the size of the step that JUNO represents.
Garnero, E. J., McNamara, A. K., and Shim, S.-H. (2016). “Continent-sized anomalous zones with low seismic velocity at the base of Earth’s mantle.” Nature Geoscience 9, 481–489.
Why read? The two blocks under Africa and the Pacific: their size, their location, and the open question of what they actually are. Essential background for the claim that the geoneutrino signal traces the same structures that seismology found.
Dye, S. T., and others (2006). “Earth radioactivity measurements with a deep ocean antineutrino observatory.” Earth, Moon, and Planets 99, 241–252.
Why read? The plan for a detector on the ocean floor, which would read the mantle without the continental crust in the way. This is the instrument that would settle the composition of the mantle most directly.
Knuth, D. E. (1997). The Art of Computer Programming, Vol. 2, §4.1. Reading: Addison-Wesley.
Why read? Balanced ternary: the three-sign notation behind the layers, including the digits behind the point. The mathematical machinery is older and more standard than it may first appear. Reading advice: a few pages; do the examples by hand.