Archaeologists have discovered a mysterious "void" inside Egypt's largest pyramid.
Using a technique developed in high-energy particle physics, researchers tracked particles called muons, which are "produced when cosmic rays strike atoms in the upper atmosphere," according to Nature. The technology allowed scientists to confirm the existence of a 30-meter-long chamber inside the 4,500-year-old Great Pyramid of Giza.
“It could be composed of one or several structures... maybe it could be another Grand Gallery. It could be a chamber, it could be a lot of things," Mehdi Tayoubi, who co-founded the ScanPyramids project that conducted the research, said, according to The Independent.
“It [the void] was hidden, I think, since the construction of the pyramid,” Tayoubi said.
News of the possible chamber made headlines back in August when researchers suggested they were on the cusp of discovering the location of the mysterious void.
"We know there is one, but we're trying to find out where," Tayoubi said at the time.
Other experts were skeptical.
Egypt's former Minister of Antiquities Zahi Hawass said that the discovery could just be "anomalies" or "small voids" between the stones.
"The core [of the pyramid] has big and small stones, and this can show hollows everywhere," Hawass said.
However, now that the scans are complete, the data checked and results published, the question is no longer whether there is a secret chamber or where it is ... but why?
Although it remains unclear what is contained in the space, Egyptologists have quickly dismissed the possibility of finding any hidden treasure.
"There’s zero chance of hidden burial chambers,” Aidan Dodson, an Egyptologist at the University of Bristol, told Nature. Dodson also does not believe the space contains any human remains, as burial chambers had been discovered long ago in the pyramid.
But experts hope that the discovery will provide significant insight into how the pyramid, considered one of the wonders of the ancient world, was built. While numerous theories have been put forward over the centuries, nobody quite knows how ancient engineers constructed the massive structures.
“There are so many theories — nice ones but also crazy ones,” Tayoubi said.
Dodson suggested that the space could be a "relieving chamber," which would lessen the weight pressing down on the Pyramid's Grand Gallery.
Also known as the Pyramid of Khufu, the monument was built between 2580–2560 B.C. during ancient Egypt's fourth dynasty. The now world-famous tourist attraction has been the muse of explorers and archaeologists for centuries.
The caliph al-Ma'mun dug tunnels into the ancient structure in 820 A.D., hoping to discover its secrets. European explorers even used dynamite to blast holes into the pyramid in the 19th century.
Today, tourists who visit the Pyramid complex in Giza can pay a fee to enter an open passageway of the structure and descend into its depths.