Archaeology

Great Pyramid Radar Study Retracted, But Its Hidden Voids Remain

✍ Arvind 📅 September 3, 2026 ⏱ 6 min

A scientific paper that once made headlines around the world for claiming to see straight through the Great Pyramid of Giza has been formally withdrawn, four years after it was published. But the retraction does not undo some of the pyramid’s most important confirmed discoveries, which were found using an entirely different method.

A Paper That Claimed to Make the Pyramid Transparent

The journal Remote Sensing retracted the 2022 study by Filippo Biondi and Corrado Malanga on August 10, 2026, after an investigation concluded that the paper contained serious methodological flaws and statistical errors that undermined its scientific conclusions. According to the official retraction notice, a reader first brought concerns to the attention of the journal’s Editorial Office, which then conducted an investigation alongside the Editorial Board. The authors were informed of the decision and, according to the notice, indicated their disagreement with it.

Biondi and Malanga’s original paper, published in October 2022, proposed an unconventional form of SAR Doppler tomography. Conventional radar faces severe limits when trying to penetrate massive stone structures, so the researchers instead argued that tiny movements within the pyramid, generated partly by background seismic vibrations, could be detected remotely from orbit and processed to reconstruct its internal architecture. Using a series of images collected by Italy’s COSMO-SkyMed satellite system, the authors reported high-resolution three-dimensional tomography of both the pyramid’s interior and subsurface, and claimed their technique had identified structures never previously discovered.

What the Retraction Actually Means

It’s worth being precise about what has and hasn’t been undone here. What has been withdrawn is not evidence that the Great Pyramid contains previously unknown spaces. Rather, the retraction concerns a particular method that purported to reconstruct the monument’s interior from satellite-based radar observations. The journal’s decision means those specific conclusions can no longer be treated as scientifically supported by the published paper, but it does not establish that every individual feature shown in the reconstructions is necessarily nonexistent. The retraction notice is specifically directed at methodological and statistical problems serious enough to invalidate the paper’s scientific conclusions overall.

Biondi has publicly challenged the decision. In a response following the retraction, he called on Remote Sensing to specify the methodological and statistical errors behind the ruling, and argued that the analytical model did not rely on statistical inference in the way implied by the notice. The formal retraction nevertheless remains in force.

Warning Signs That Predated Publication

One of the more revealing aspects of the case sits not in the retraction notice itself, but in Remote Sensing’s publicly available peer-review record. During review of the version eventually published in 2022, one reviewer explicitly wrote that validation of the results was missing, asked the authors to provide considerably more methodological information that would allow other scientists to reproduce the experiment, and described the conclusions as weak from a validation standpoint.

The record also preserves reviews tied to an earlier submission of the manuscript, where the concerns were even more specific. One reviewer questioned whether the features visible in the tomograms represented actual objects and cavities, or artifacts created by the technique itself, and argued that because the method was novel, it should have first been subjected to carefully controlled validation experiments using known targets before being applied to the Great Pyramid. That same review flagged that several tomographic images lacked meaningful dimensional axes, making it difficult to determine the scale of apparent structures, and warned against subjective alignment between reconstructed radar images and diagrams of the pyramid’s known architecture. These review comments don’t prove the 2026 retraction resulted directly from these specific objections, since the journal hasn’t drawn that connection publicly. They do show, however, that questions over validation and interpretation were already circulating years before the paper’s eventual withdrawal.

What Scientists Have Actually Confirmed Inside the Pyramid

The retraction should not be confused with a separate, well-established body of evidence produced by the ScanPyramids project, which relies on an entirely different physical technique: cosmic-ray muon detection.

In 2017, researchers reported in the journal Nature the discovery of the ScanPyramids Big Void, an unknown space positioned above the pyramid’s Grand Gallery. Instead of attempting to image through the pyramid with satellite radar, researchers used muons, high-energy particles produced when cosmic rays interact with Earth’s atmosphere, capable of passing through substantial amounts of stone. Crucially, this anomaly wasn’t based on a single instrument. It was first observed with nuclear emulsion films inside the Queen’s Chamber, then confirmed with scintillator detectors, and independently detected again using gas detectors positioned outside the pyramid. All three separate muon techniques indicated a void with a minimum length of about 30 meters, whose purpose remains unknown.

A second unknown structure was later identified behind the chevron-shaped masonry on the pyramid’s north face. In 2023, a study published in Nature Communications used two independent cosmic-ray muon detection systems to characterize what is now known as the ScanPyramids North Face Corridor, with measurements indicating a passage roughly nine meters long with a cross-section of about two by two meters.

Independent Confirmation, Method After Method

The difference in scientific rigor between the two approaches becomes even clearer in what came next. In 2025, researchers reported in Scientific Reports that the North Face Corridor had been examined using three additional, entirely different non-destructive methods: ground-penetrating radar, ultrasonic testing, and electrical resistivity tomography. Because each technique relies on different physical principles and carries different limitations, agreement between them provides an important way of testing whether an apparent anomaly corresponds to a genuinely real feature rather than a processing artifact.

A separate Scientific Reports study published in November 2025 focused specifically on electrical resistivity tomography, and again detected a resistive anomaly consistent with the North Face Corridor, providing yet another independent line of evidence for a structure first identified through muon radiography years earlier.

Two Very Different Standards of Evidence

The scientific picture at Giza is therefore more complicated than a simple conclusion that a claim about hidden corridors has been disproved. The 2022 SAR paper and the established ScanPyramids discoveries rest on fundamentally different kinds of evidence. The former attempted to infer detailed internal structures from satellite observations of microscopic movements, using a single, novel, unvalidated technique, and has now lost the scientific endorsement of the journal that originally published it. The Big Void and North Face Corridor, by contrast, have each been detected through multiple independent measurements using different physical principles, with the corridor specifically confirmed by several distinct non-invasive techniques.

That distinction matters enormously at a monument where images of supposed chambers, tunnels, and underground structures can circulate internationally long before any independent confirmation exists. The retraction changes what can responsibly be said about the SAR reconstructions of the Great Pyramid. It does not erase the pyramid’s genuinely confirmed hidden spaces. The Big Void and North Face Corridor have survived repeated, independent measurement. The 2022 satellite-radar reconstruction has not survived scientific review.