The Shroud of Turin in the News

By Edvard A. Hemmingsen

And we thought that it had been "buried" permanently, for good reasons.

The story of the shroud is familiar. After Jesus was killed, his body presumably was wrapped in a shroud and placed in a burial cave as the custom was at that time. What happened to the body and its shroud afterwards is most uncertain. It is said that one of Jesus' disciples gave the shroud, which somehow had the image of a man on it, to a king in Turkey decades later. It was taken to Constantinople in 944 and ended up in the hands of the crusaders two and a half centuries later. Then the shroud disappeared for about 150 years.

This is the dull part of the story; much of it is dubious and difficult or impossible to verify. But then it gets more interesting. A piece of linen cloth, with faint images of the front and the back of a man who appears to have crucifixion markings, came into the possession of a famed knight in 1354. When it was exhibited in 1389, the local bishop declared it to be false as he had the confession of the artist who painted it. The bishop notified antipope Clement VII about the matter, and he in turn sanctioned the linen as a object of devotion but only as a substitute for the real shroud of Jesus.

Yet, all later popes up to recent times allowed it to be used as the real shroud, postulating that the image was that of Jesus. It was moved to Turin in 1578 and was displayed rarely after that.

Only in the last three decades have scientists begun to have some limited access to the shroud, for the purpose of finding out how the image was produced and determining its age. A faint reddish stain on the shroud proved not to be blood, but red ochre and vermilion paint pigments, dispersed in a collagen tempera. In spite of this evidence, one investigator claimed that DNA analysis of the stain suggested that it is blood, from a male no less! Of course, as everybody knows, dried blood is brown and not red (due to the ready oxidation of iron in the hemoglobin). There also was a topology problem. How can an imprint from the surface of a three-dimensional object appear as a two-dimensional rendering of the object? It cannot. For example, if the distance between the tips of the ears is measured following the surface contour over the face, it is much longer than the width (of the head) measured in a life-size projection to a flat surface. Even though the shroud purportedly was draped over or wrapped around the head, the image is not enlarged horizontally on the flattened shroud; it looks "normal", not very distorted.

But this aside, the critical issue has been to find the age of the shroud. In 1988, the archbishop of Turin allowed a scientific team to cut a substantial sample (1 x 7 cm) from the shroud for radiocarbon dating, a rock-solid method for determining the age of carbon-based material from hundreds to thousands of years old. It has been used extensively for many different materials and conditions with unequivocal success. Verification comes from the dating of objects that can be precisely dated by historical records and other means.

The shroud sample was cut into three pieces, each going to a prestigious laboratory in three different countries. Each did their testing independently of the others. Each sample was further subdivided, cleaned and treated in different ways. The results published in Nature in 1989 (vol. 337, p. 611-615), were not surprising; they date the shroud to 1260-1390 with better than 95% confidence. The range is narrower with less confidence, and wider with higher confidence. This covers the period when the shroud first appeared. Conclusion: the linen of the Shroud of Turin is medieval in origin. The Roman Catholic church accepted this conclusion, but encouraged Christians to worship the shroud as an inspiring pictorial image of Jesus.

But believers and attention-seekers do not give up easily. Part of the shroud had been charred in a fire. Claims were made that burning the carbon changes the date. No, it does not; besides, the dated sample was removed from the part of the shroud that was not charred. Then it was suggested that the samples were contaminated by bacteria and other material and that their carbon (being more recent) would mix with the more ancient carbon of the linen and cause a too young date to be obtained. Hardly. If an age error of 1300 years was to be added to the 700 years determined, 60% of the weight of the linen fibers (after their varied and thorough cleaning) would have to be of modern origin.

Then in early August this year, according to a report by Ricki Lewis in The Scientist (Sept. 13, 1999), the debate about the shroud was resurrected. At the XVI International Botanical Congress, an expert on the flora of the Middle East claimed that the faint traces of flowers which can be seen on the shroud can be identified as species natural to the Jerusalem-Hebron area. One of them has a very limited range of distribution outside that area today. Purportedly, unpublished pollen analysis made by others are consistent with the identification of the flower species. By also leaning on some unsubstantiated "evidence" claims and ideas from past years, the investigator attempts to place the origin of the shroud to a period before the 800 year time period, thus rejecting the radio-carbon dating. All of this was picked up by the eager news media.

With only second hand, very limited information available it is impossible to assess how much of this may just be wishful thinking and how much of it may be real. But one thing is almost certain. If the study makes it into a respectable, peer-reviewed journal, it will spark some lively debate. If not, it will still serve the shroud believers as they will have another piece of "scientific proof" for their cause.