Prosecutors et al., 2023
In 2016, scientists using muon imaging detected signals indicating hidden corridors behind the famous chevron blocks on the north face of the Great Pyramid of Giza in Egypt. The following year, the same team discovered a mysterious cavity in another area of the pyramid, believing it to be a hidden chamber. His two independent teams of researchers using two different muon imaging methods have successfully mapped the corridor for the first time, according to a new paper published in Nature Communications. Former Egypt’s antiquities minister Zahi Hawass called it “the most important discovery of the 21st century”.
As we have previously reported, there is a long history of using muons to image archaeological structures, and cosmic rays provide a steady supply of these particles, facilitating the process. An engineer named EP George used them to measure tunnels in Australia in the 1950s. However, Nobel Prize-winning physicist Luis Alvarez discovered that when he worked with Egyptian archaeologists to use this technique to search for hidden chambers in the pyramid of Khafre at Giza, the muon his I put the imaging on the map. It worked in principle, but I couldn’t find the hidden room.
There are many variations of muon imaging, but they all typically require a gas-filled chamber. As muons blaze through the gas, they collide with gas particles and give off telltale flashes. This flash of light is recorded by a detector so scientists can calculate the particle’s energy and trajectory. This is similar to X-ray imaging and ground-penetrating radar, except for naturally occurring high-energy muons rather than X-rays or radio waves. Its higher energy makes it possible to image thick, dense materials such as the stones used to build pyramids. The denser the imaged object, the more muons are blocked and cast a distinct shadow. Hidden chambers within the pyramids are visible in the final image due to fewer blocking particles.
Muons are being used to search for illegally transported nuclear material at border crossings and to monitor active volcanoes in hopes of detecting when they will erupt. In 2008, scientists at the University of Texas at Austin set out to follow in Alvarez’s footsteps, reusing an old muon detector to search for possible hidden Mayan ruins in Belize. Physicists at the Los Alamos National Laboratory also released a portable version to unlock the secrets of the construction of the towering dome (Il Duomo) atop the Basilica of St. Mary of the Flowers in Florence, Italy, designed by Filippo Brunelleschi. We are developing a muon imaging system for Early 15th century. The dome has been plagued with cracks for centuries, but muon imaging could help conservationists understand how to repair it.
As Annalee Newitz wrote for Ars in 2017, King Khufu (2509 BC-2483 BC) ordered the construction of the Great Pyramid at Giza about 4,500 years ago. The structure remained sealed until 820 AD. At this time, the caliph Almamun broke his one of its walls and inside he discovered three chambers. The Great Corridor of the “Grand Gallery” with the King’s Chamber, the Queen’s Chamber and the Abandoned Underground Chamber. There is also a descending corridor, an ascending corridor and passages dug in the Middle Ages, which are now used as entrances for tourists.
