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Scientists at Chicago’s Field Museum of Natural History have peered beneath the wrappings of ancient Egyptian mummified human remains to uncover new details about their identities and how they were prepared for the afterlife — all without removing a single piece of linen.

In September, staff members rolled 26 of the mummies on display at the museum on specially built carts to the parking lot to be put through a mobile CT scanner. The nondestructive technology resulted in thousands of X-rays of the mummies and their coffins. When stacked together, the X-rays created 3D images that revealed the skeletons and artifacts inside.

The new insights are helping to shed light on Egyptians’ mortuary practices more than 3,000 years ago as well as what they thought was important to carry into the afterlife.

While the scans took about four days to complete, the processing and analysis of the 3D renderings may take up to three years, said JP Brown, senior conservator of anthropology at the museum.

Researchers at the Field Museum scan a mummified individual displayed in the "Inside Ancient Egypt" exhibition.

In addition to providing insights about the best methods to preserve the mummies for generations, the scans also offer a chance to understand the individuality and personal details of each mummified Egyptian in a respectful way.

“From an archaeological perspective, it is incredibly rare that you get to investigate or view history from the perspective of a single individual,” said Stacy Drake, human remains collections manager at the Field Museum. “This is a really great way for us to look at who these people were — not just the stuff that they made and the stories that we have concocted about them, but the actual individuals that were living at this time.”

Museum scientists are hoping to learn more about the mummified individuals through the scans, including their sex and age.

Preparing for the afterlife

Inside Ancient Egypt” is one of the most popular exhibits at the museum and includes a three-story replica of a type of tomb called a mastaba. The tomb’s burial chambers, dated to 2400 BC, contain 23 human mummies and more than 30 animal mummies.

Ancient Egyptians believed that the soul remained inside the body after death, so embalmers mummified bodies to preserve the spirit for the afterlife, according to Field Museum scientists.

The spiritual and biological ritual of mummification could take 70 days, including removing internal organs except for the heart because it was thought to be the soul’s home. Embalmers used salt to dry the bodies, then wrapped them in linens, sometimes writing prayers or including protective amulets. A ceremonial burial would be the final step to send the mummified person on to the afterlife.

Any internal organs removed during the process were typically placed in canopic jars, each featuring an iconographic lid with one of the four sons of the Egyptian god Horus to protect each organ. Imsety was the human-headed god who protected the liver, while Hapy had the head of a baboon and protected the lungs. Jackal-headed Duamutef protected the stomach, and falcon-headed Qebehsenuef watched over the intestines.

But the new CT scans revealed that some embalmers chose to make packets for the organs and reinsert them within the mummies. Within the packets were wax statues of the sons of Horus responsible for protecting the organs. The statues helped the museum scientists identify the organs in each packet, Brown said.

Ancient Egyptians viewed the afterlife in a similar way to how modern people think about retirement savings, according to Brown.

“It’s something you prepare for, put money aside for all the way through your life and hope you’ve got enough at the end to really enjoy yourself,” he said. “You want to be living your best afterlife.”

Not every ancient Egyptian was mummified, but the restricted practice apparently was common among the upper middle class and those of high status, Brown said.

Burials for pharaohs, the rulers of ancient Egypt, were comparable to the status of a top-of-the-line automobile. Meanwhile, Lady Chenet-aa, one of the museum’s most popular mummified individuals, had a burial on the scale of a high-end luxury car, Brown said.

Solving a coffin mystery

Lady Chenet-aa lived about 3,000 years ago during the 22nd Dynasty in Egypt.

The new scans helped scientists estimate that the high-status woman died in her late 30s to early 40s, while wear on her teeth shows that the food she ate contained grains of sand rough on the enamel.

Stuffing was placed in her trachea to ensure her neck wouldn’t collapse, and artificial eyes were placed in her eye sockets to guarantee she had them in the afterlife, Drake said.

“The additions are very literal,” Brown said. “If you want eyes, then there needs to be physical eyes, or at least some physical allusion to eyes. They’ll put a prosthetic in to make sure that you’ve got everything you need when you go to the afterlife.”

Lady Chenet-aa was wrapped in expensive layers of linen before being placed in a decorated cartonnage coffin, or a papier-mâché-like funeral box. But the biggest mystery about the Egyptian was how she was placed in the box in the first place.

There were no visible seams, and only a tiny opening at the feet — not wide enough to accommodate sliding the body into the box.

The new scans revealed the cartonnage’s underside for the first time, showing that the box was essentially laced shut at the back before being plastered over to create a seamless aesthetic, Brown said.

The team said that embalmers stood the mummy upright and that the cartonnage was softened with humidity to make it flexible so they could closely mold it around the body. A slit was cut at the back of the cartonnage so the body could be placed inside, and then it was closed up and laced shut.

While a CT scan can’t detect colors, it revealed the artistic designs etched into the top of the cartonnage, including indents for the knees.

The team also took a closer look at Harwa, a mummified individual who lived around 3,000 years ago and was a granary’s doorkeeper. Analysis of scans shows he was in his early to mid-40s when he died. From all appearances, he had a high social status and lived a comfortable life.

“We started looking at these two individuals primarily just to see a better idea of age and sex and any obvious pathologies or things we might see,” Drake said. “One thing that we are seeing is pretty extensive wear on their teeth because they’re living next to the desert, and there’s going to be a lot of sand in their food, or they’re using stone to grind their food. But we’re not seeing a lot of wear on the body for these two individuals in particular who were higher status and likely not conducting a lot of physical labor.”

The CT scans help scientists understand any chronic conditions individuals may have had, but the technology also aids in correcting cases of mistaken identity. While Harwa and Lady Chenet-aa both clearly had coffins made just for them, not every mummified individual was as fortunate.

One of the coffins is etched with hieroglyphics that indicate a priest was buried inside, but the individual was a 14-year-old boy much smaller than the coffin.

“We know that sometimes people really wanted to be mummified but didn’t necessarily always have the best means to do so,” Drake said. “You could get a discount coffin by borrowing or using someone else’s.”

Caring for mummified persons

In the late 19th century as archaeologists uncovered mummies in Egypt’s deserts, they would unwrap them to see what they could learn. Now, the emphasis is on protecting mummified individuals to help them last for thousands of more years, Brown said.

Today, practices around mummified individuals have shifted to show respect for how human remains are presented and displayed in museum settings, Drake said. The Field Museum also had conversations with Egyptian representatives about returning the mummies to Egypt, but those officials requested that the mummies remain on display at the Chicago museum, she said.

A Field Museum researcher analyzes composite scans of a mummified child.

Harwa’s adventurous afterlife is one example of how things have changed. In 1939, he became the first mummified person to fly on an airplane, and he was taken to a Broadway show upon his arrival in New York City. On display at the New York World’s Fair for two years, he then returned to the Field Museum after getting lost in the luggage and being sent to San Francisco.

“It’s maybe not what we would consider ethical anymore,” Drake said. “One of the big things for these ancient Egyptian individuals is how you continue to live after death. And that is part of his story and his journey.”

The museum wants to convey the idea that mummies are people, rather than art objects, Brown said.

“We are trying to understand them as people so that we can share those stories and insights with the general public to kind of rehumanize and shift the narratives to be more respectful and give some more dignity to these mummified individuals,” Drake said.