The Pyramid That Wouldn’t Give Up Its Secrets

How ScanPyramids’ cosmic-ray breakthrough set the stage for Filippo Biondi’s radar-tomography quest—and the strange new maps it produced.

At Giza, the Great Pyramid looks like pure certainty: a mountain made by humans, four crisp edges pinned to the horizon. But in the modern era, certainty is exactly what the pyramid has learned to resist. Not because it is crumbling into mystery, but because every time researchers aim a new kind of instrument at it—particles, heat, sound, radar—the stone answers back with fresh geometry.

Over the last decade, that conversation has gotten dramatically more technical, and far more cinematic. It begins with cosmic rays from deep space. It leads, improbably, to satellites and the idea that the pyramid can be “seen” not by penetrating it with a signal, but by watching how it moves.

When cosmic rays found a room

For years, the Great Pyramid’s internal plan felt like a closed book: the Descending Passage, the Grand Gallery, the King’s Chamber, the Queen’s Chamber—legendary, surveyed, argued over, and seemingly finished as a story.

Then ScanPyramids arrived with a method that sounds like science fiction but behaves like engineering: muography, or cosmic-ray muon radiography. Muons are ultra-penetrating particles that constantly rain down through the atmosphere. Put detectors in the right places, wait, and the pyramid effectively becomes a filter. Denser areas block more muons; emptier areas let more pass. The result is not a photograph, but a density map—an X-ray logic translated to a monument the size of a small hill.

In 2017, the ScanPyramids team reported what made the wider world sit up: a “large void” above the Grand Gallery, with a cross-section comparable to the gallery itself and a minimum length of about 30 meters.

That discovery mattered not just because it was big, but because it was the first major internal structure reported in the Great Pyramid since the 19th century—proof that the most famous building on Earth still had undisclosed volume.

Then came another find, more surgical and easier to picture: a corridor-shaped structure behind the so-called Chevron zone on the pyramid’s north face. ScanPyramids published a precise characterization in 2023, describing a corridor at least five meters long. And in 2025, researchers reported using Electrical Resistivity Tomography (ERT)—a different non-destructive technique—to detect the presence of that same North Face Corridor.

By this point, the pyramid had become something like a reluctant patient in a very advanced scan suite: muons, resistivity, radar, ultrasound—methods stacked, compared, fused. The principle was simple: you don’t take one image and declare victory; you return with another instrument and see if the stone repeats the same answer.

Enter Filippo Biondi, looking for a different kind of visibility

If ScanPyramids gave the world a new way to discover voids, Filippo Biondi wanted a new way to reconstruct the pyramid—more like a 3D model than a single “there’s something here” marker.

Biondi, an engineer at the University of Strathclyde, and Corrado Malanga, at the University of Pisa, put their idea into a 2022 paper with a title that reads like a dare: “Synthetic Aperture Radar Doppler Tomography Reveals Details of Undiscovered High-Resolution Internal Structure of the Great Pyramid of Giza.”

The hook is this: conventional radar does not easily “see” through thick stone. The authors say so plainly. But instead of trying to force radar to penetrate the monument like a drill bit made of electromagnetism, they pivot to a different phenomenon—micro-movements.

The Great Pyramid is not perfectly still. It’s constantly being excited by the background noise of the planet: tiny seismic waves, wind, distant vibrations. Biondi and Malanga propose that a long series of satellite SAR images can capture subtle motion signatures and, from those signatures, create a form of tomographic reconstruction—an interior map inferred from how different parts of the structure respond. Their paper describes processing SAR image series from Italy’s second-generation COSMO-SkyMed satellite system and reports what they call “high-resolution full 3D tomographic imaging” of the pyramid’s interior and subsurface.

It’s an unusually poetic claim for a remote-sensing journal. In the abstract, they go so far as to say the pyramid “becomes transparent” when observed in this micro-movement domain.

The new maps: familiar chambers, then unfamiliar “tags”

One reason Biondi’s story caught fire is that it doesn’t start with fantasy. It starts with orientation: a reconstruction that aligns with known architecture—chambers and corridors already documented by explorers, surveyors, and modern missions.

Then the paper pivots into its headline promise: additional structures and connections that the authors label and catalogue. In the article’s tabulated structure list, they include items such as a “little void,” a “front corridor,” and a “big void,” alongside multiple corridors and complex structures.

If you’re a reader steeped in ScanPyramids lore, those terms ring bells. “Big void” is now a famous phrase, and ScanPyramids’ 2017 muon work is the reason. The corridor behind the Chevron zone is a ScanPyramids result as well—and, by 2025, had been investigated with ERT in a separate Scientific Reports study.

In other words, Biondi’s reconstructions live in an ecosystem where some voids are already known from other techniques—creating an intriguing narrative rhythm. The pyramid offers a few confirmed surprises (ScanPyramids). Then a new method arrives (Biondi’s SAR Doppler tomography) that claims to render not just a dot on the map, but a wider network of shapes.

It’s easy to see why the idea appeals. It promises a kind of remote sensing that feels less like “detecting emptiness” and more like “recovering blueprint.”

How the story escaped the journals and hit the culture

In March 2025, the subject leapt from technical circles into the loud main square of internet fascination, when claims circulated about a vast underground network beneath the Giza pyramids, attributed to “radar images.” Euronews captured the moment as a full-on public dispute—researchers promoting an extraordinary underground interpretation, and Egyptologists pushing back hard.

What made it combustible was scale. People weren’t just talking about a corridor or a void; they were talking about a subterranean system—vertical shafts, sweeping features—something closer to a hidden infrastructure than a sealed tomb.

Biondi’s name became part of that conversation, especially because his published work is explicitly satellite-SAR-based and explicitly ambitious about internal and subsurface imaging.

Official responses arrived quickly. Zahi Hawass issued a public statement on March 26, 2025, calling the viral claims “false” and disputing the radar narrative around the “Khafre Project.” Newsweek, covering the same flare-up, summarized Hawass’s dismissal and the broader controversy around the underground-city claim.

And yet—this is the part that keeps the story alive—controversy doesn’t necessarily kill curiosity. It concentrates it. Once the pyramid is framed as a place where new scanning methods can still produce surprises, each new dataset feels like a possible next chapter.

Why Biondi’s approach feels so different

ScanPyramids is, in a sense, blunt and elegant: cosmic particles in, density map out. The results arrive as bounded mysteries—“there is a void here”—that can be tightened through additional measurements.

Biondi’s approach is more like listening than looking. It suggests that if you can measure the pyramid’s tiny involuntary motions across time, you can invert those signals into structure. It’s a seductive proposition because it reframes the monument: not as static stone to be penetrated, but as a responsive object whose internal layout shapes how it vibrates.

It also has a dramatic practical implication: satellites don’t need permission to stand in a corridor for months. They don’t need to place instruments in a chamber. They observe from above, again and again, and build a time-series memory of the structure’s behavior.

That’s the heart of the Biondi story: the pyramid as a signal processor, a giant stone instrument played by Earth’s background noise.

The present tense: the pyramid as a testing ground for modern sensing

If you zoom out, what’s happening at Giza is bigger than any single “void” or “corridor.” The pyramids have become a proving ground for non-destructive investigation—an arena where particle physics, geophysics, and satellite remote sensing all try to earn their keep on the world’s most scrutinized architecture.

ScanPyramids gave the field a modern myth grounded in peer-reviewed measurement: the Big Void above the Grand Gallery. It also helped normalize the idea that small, targeted anomalies—like the North Face Corridor—can be detected, characterized, and then corroborated with other techniques such as ERT.

Biondi’s work, meanwhile, leans into a more expansive dream: that satellites can reconstruct interior and subsurface detail at high resolution via micro-motion analysis, producing structured inventories of rooms, corridors, and connections—including items explicitly labeled as “little void” and “big void.”

The next chapter—if the story continues in a way that satisfies both curiosity and craft—will look like what Giza has increasingly demanded: converging evidence. Not one picture, but a stack of them. Not one sensor, but a chorus. And perhaps, in the end, a minimally invasive look inside a newly mapped space—something as small as a camera probe that turns a compelling model into a confirmed room.

Until then, the Great Pyramid keeps doing what it has always done best: standing perfectly still while the most advanced tools of each era circle it, trying to learn what it’s been hiding in plain sight.