This article accompanies the textbook The Real World of Chemistry 6th ed by Lois Fruen Kendall/Hunt Publishing ISBN 0-7872-9677-5

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While the mummies of the ancient pharaohs of Egypt in the Cairo Museum are the most famous in the world, the mummy named Lady Teshat at the Minneapolis Institute of Arts is famous in her own right. She may have been the first mummy to be X-rayed back in 1918, and she was the second mummy in the United States to have a CT (CAT) scan (McEnroe). She was also the first mummy in the world to be scanned using NMR.

I was fortunate to speak with Dr. Derek Notman, who initiated and oversaw the CT and NMR scans. He works at Methodist Hospital in Minneapolis. He talked about Lady Teshat and explained CT scanning.

The 1918 X-ray showed that Lady Teshat died when she was about 15 or 16 years old, 3000 years ago. Doctors who examined the X-ray plates could determine this because the growth plates of the long bones of her arms and legs were not fully fused, which usually occurs by the age of 20. The X-ray also revealed an unusual aspect of her mummification. She was wrapped with a second skull between her legs. Of all the mummies that have been X-rayed, only this one has a second skull.

To complicate matters further, no jewelry or amulets showed up on the X-rays. The hieroglyphic text on her elaborately painted coffin says she was married, well educated, and was the daughter of the treasurer of the Temple of Amen at Thebes. In that position, Lady Teshat’s father would have been one of the most powerful men in Egypt. So, it is almost unthinkable that Lady Teshat would have been buried with no jewelry or amulets.

The mysteries that surrounded Lady Teshat intrigued Dr. Notman. He had studied anthropology and archaeology in college before pursuing medicine and was curious about this unusual mummy. His specialty is radiology, so he proposed giving her CT and NMR scans in hopes of solving the mysteries about her.

Lady Teshat was taken to the Mayo Clinic for the scans. There she was draped with a white sheet, like any other patient, and sent into the CT scanner. A CT scanner uses X-rays and a detector, which are mounted on a circular frame, and rotated synchronously and equally in opposite directions around the subject–in this case the mummy. Instead of a photographic plate, which is used in traditional X-ray machines, a CT scanner uses crystals of NaI to absorb the photons of radiation that pass through the subject. The number of photons the detector receives depends on what substances it encounters. X-rays do not penetrate all things equally well. Some things, such as bone and tissue, absorb X-rays. The number of photons, which reach the detector, depends on the type and density of the material through which the X-rays pass. The photons received by the detector are converted into electrical signals, which are recorded by a computer (Notman).

Computer analysis of the data from the CT scan resulted in a series of three-dimensional "slices" of Lady Teshat’s mummy. This eliminated the problem of overlapping features that is characteristic of traditional X-raying (Filer). The slices could also be viewed from every angle since 97 cross-sectional views were taken of the mummy. It was possible to zoom in on one slice to study a particular part of the mummy (Putman 123).

Images from NMR scan produced only weak signals and no image resulted. This is because NMR images are produced by the hydrogen atoms in water molecules of tissues. Since Lady Tashet was thoroughly desiccated, there were no hydrogen atoms present to produce the image (Art Meets Science).

But, the CT scan revealed a lot about Lady Teshat. It confirmed that she did die when she was young and showed evidence of a bone infection in her hip and right knee. Even more interesting, it revealed that her ribs were crushed, the bones of her left arm were broken, her tissues were damaged, and her body was twisted. She also had slashes on her feet. In addition, the scan showed that the second skull was from an adult male. It was fractured and had a broken lower jaw (Mummy of Lady Teshat).

Modern romantic tales suggest that Lady Teshat was caught with a lover, killed by her husband, and buried with her lover’s head (ibid). But, Dr. Notman says, "If her injuries occurred when she was alive, she would not have died from them." Some scholars think the embalmers were careless. But, the CT scan indicates that the mummy was carefully wrapped in linen and her carton is in excellent condition.

Dr. Notman believes that Lady Teshat’s mummy was damaged in antiquity by tomb robbers in their haste to steal her jewels and amulets. He thinks the temple priests rewrapped Lady Teshat’s body after the robbery. He suggests that they included the second skull when rewrapping her, because it was all that was left of another mummy that was damaged in the robbery. The missing jewelry and amulets provide convincing evidence for his theory.

Notman says that he also scanned the three other mummies in Minnesota. One of those can be seen at the new Science Museum of Minnesota. His CT scans are on display there with that mummy.

Modern medicine has helped to solve the mystery of Lady Teshat in a non-invasive way without disturbing her wrappings. CT scanning is being used more and more to examine mummies.

Photo of Lady Tashat being put into a CT scanner is printed with permission from the Minneapolis Institute of Arts. www.artsMIA.org.

I enjoyed interviewing Dr. Notman and appreciate his help on this paper. I think it is neat that a pioneer of this important archaeological technique is one of our local Minneapolis doctors!

"Art Meets Science." Arts. Nov. 1983.

"Solving an Ancient Mystery." Discover. Nov. 1984.

Filer, Joyce. "Revealing Hermione’s Secrets." Egyptian Archaeology. Fall 1997.

Foster, Gregory S. John E. Connolly Jr., Jin-Zhao Wong, Emily Teeter, Patricia M. Mengoni. "Evaluation of an Ancient Egyptian Mummy Using Spiral CT and 3-D Reconstructions." www.rad.rpslmc.edu/rsnamumie/rsnamumie.html.

McEnroe, Paul. "Mummy’s Mysteries Probed with CAT Scan." Minneapolis Star Tribune. 2 May, 1983.

Moss, Carol M. "Modern Medicine Looks at Ancient Mummy." Scholastic Science World. 30 Mar. 1984.

"Mummy of Lady Teshat." Minneapolis Institute of Art.

Notman, Derek. Personal interview. 16 Dec. 1999.

Putman, James and George Hart. Ancient Egyptians. New York: DK Publishing, 1996.

Visualization of CAT scans. www.tc.cornell.edu/Edu/SPUR/SPUR94/Reports/SPUR_Martha_Report/html