The pyramids of ancient Egypt have harbored their secrets for some 4,500 years. But thanks to some incredible technology, archeologists have finally begun to unlock them.

The Scans Pyramids project uses “cosmic rays” to create maps that show the internal structures of Egypt's pyramids. On Tuesday, April 26, archeologists and researchers from the project unveiled their latest work.

The images show the internal chambers of the 4,600-year-old “Bent Pyramid,” a 105-meter (345-foot) limestone monument found just 40 kilometers (25 miles) south of the modern Egyptian capital, Cairo. For the first time, the images also clearly show the shape and structure of the pyramid's second chamber.

Known in ancient times as the Southern Shining Pyramid, it’s thought to be one of Egypt's earliest pyramids. As you can almost tell from its rather weird look, this particular pyramid is seen as a transition between step-sided and smooth-sided pyramids.

The technique to look inside is comparable to how X-rays work, except it relies on muon particles. These particles, which originate from the interactions of cosmic rays from the distant universe with the atoms of the upper atmosphere, can penetrate hundreds of meters of stone before being absorbed. By placing 40 muon-sensitive films deep inside the pyramid, the researchers can work out the thickness of the stone within the structure. After 40 days of exposure to muon particles, the information from these films were put together to create an image.

This is just the beginning of the incredible work you can expect to see from this project. They’re now going to use the same technique on other Old Kingdom pyramids such as Khufu, Khafre, and the Red Pyramids.

The Bent Pyramid, as seen without the use of "cosmic ray" detectors. Image credit: Gurgen Bakhshetsyan/Shutterstock