Thousands of years after it was built, the Great Pyramid of Giza continues to captivate the imagination of people the world over, and we’re still uncovering its mysteries. Now, thanks to advances in particle physics, scientists have discovered a massive void hidden inside the famed structure.

Also called Khufu’s Pyramid, Egypt’s Great Pyramid was erected around 2500 BC, and is the last of the seven wonders of the ancient world. It’s been closely studied by archaeologists for centuries, but scientific advances in cosmic-ray collisions are making new breakthroughs possible. Using that technology, an international team of researchers from the ScanPyramids project detected a 100-foot-long empty space inside the pyramid. (ScanPyramids was established by the Egyptian Ministry of Antiques in 2015 to study the ancient structures utilizing non-invasive technologies.) Read more