Neutrinos From Deep Inside Earth Provide a New Picture of the Mantle

Recommendable! Geoneutrinos versus Helioneutrinos!

"... This is the SNO+ neutrino experiment, buried deep within the Creighton mine at Snolab, an underground physics laboratory in Sudbury, Canada. SNO+ consists of an acrylic sphere lined with nearly 10,000 sensitive light detectors and filled with 780 tons of oily liquid scintillator, which flashes when lit up by energetic particles. The water around the device and the rock above it shield the detector from the glare of cosmic radiation, allowing the flickers of less common particle interactions to shine through. ...

Even more elusive — so much so that after decades of searching, scientists have detected only a few hundred of them — are geoneutrinos. ...

Geoneutrinos are produced in processes that heat the interior of the planet. This heat plays a major role in powering the flow of rocks in the mantle, which shapes everything from plate tectonics to Earth’s magnetic field.

It comes from two main sources:

heat left over from the planet’s formation, and

heat produced by the decay of uranium, thorium, and potassium in the rocks of the mantle and crust. ...

In counting geoneutrinos, physicists can get a direct measure of Earth’s vital heat-producing elements. ...

The first detection of geoneutrinos, by an instrument in Japan called Kamland, was reported in 2005.

In 2009, the Borexino detector in Italy reported catching several dozen more.

In November 2025, SNO+ reported(opens a new tab) its first detection, bumping up the number of observed geoneutrinos by about 50.

What makes the detections at SNO+ special is the experiment’s location: These are the first geoneutrinos measured in the western hemisphere, offering a new perspective on Earth’s radioactive interior.

Major uncertainties remain in interpreting the results from these experiments, but researchers’ best estimates suggest that each site is measuring a different flux. “It could be that that’s the first hint that the mantle is not uniform,” ..."

Neutrinos From Deep Inside Earth Provide a New Picture of the Mantle | Quanta Magazine "A global constellation of neutrino detectors is creating a never-before-seen view of the radioactive elements that power Earth’s tectonic heat engine"

The JUNO experiment, located outside the city of Guangzhou in China, is expected to report its first geoneutrino detections this year.

The SNO+ experiment sits deep underground, shielded from cosmic rays beneath 2 kilometers of rock.