Turin shroud controversy envelops pair

COLORADO SPRINGS, Colo. — The tie that binds John and Rebecca Jackson is about 4 feet by 14 feet, woven of herringbone twill linen. It once led to their romance; years later, it dominates their thoughts and fills their conversations.

It brought Rebecca, an Orthodox Jew, to the Roman Catholic Church; it led John to suspend himself from an 8-foot-tall cross to study how blood might have stained the cloth. Together, the two have committed to memory every crease, scorch mark and unexplained stain in their years-long pursuit of the mystery:

Is the Shroud of Turin — which purportedly bears the image of a crucifixion victim — the burial cloth of Jesus?

In 1988, science seemed to put that question to rest.

Radiocarbon dating by three separate laboratories showed the shroud originated in the Middle Ages, leaving the "shroud crowd" reeling. Shroud skeptics responded, "We told you so." The Catholic Church acknowledged it could not be authentic. Many scientists backed away.

Result questioned

John Jackson, one of the shroud's most prominent researchers, was among those who insisted the results made no sense. Too much else about the shroud, they said, including characteristics of the cloth and details in the image, suggested it was much older.

Twenty years later, Jackson, 62, is getting his chance to challenge the radiocarbon dating. Oxford University, which participated in the original radiocarbon testing, has agreed to work with him in reconsidering the age of the shroud.

If the challenge is successful, Jackson hopes to be allowed to re-examine the shroud, which is owned by the Vatican and stored in a protective chamber in the Cathedral of St. John the Baptist in Turin, Italy.

Jackson, a physicist who teaches at the University of Colorado, hypothesizes that contamination of the cloth by elevated levels of carbon monoxide skewed the 1988 carbon-14 dating by 1,300 years.

"It's the radiocarbon date that to our minds is like a square peg in a round hole. It's not fitting properly, and the question is why," he said.

On that point, Christopher Ramsey, head of the Oxford Radiocarbon Accelerator Unit, seems to agree. "There is a lot of other evidence that suggests to many that the shroud is older than the radiocarbon dates allow and so further research is certainly needed," according to a statement on his Web site.

Steven Schafersman, a geologist who maintains a skeptical Web site about the shroud, dismissed the effort as one that's bound to fail. "He's had other ideas, but they've all been shot down, and this one will be shot down too," he said of Jackson.

Others are challenging the radiocarbon date. At a conference sponsored by the Shroud Science Group at Ohio State University last weekend, the Los Alamos National Laboratory presented findings that the 1988 test results were flawed because the samples came from a portion of cloth that may have been added to the shroud during medieval repairs.

The shroud's historical record dates to 1349, when a French knight wrote to the pope of his possession of a cloth he described as the burial shroud of Christ.

In 1978, a team of scientists led by Jackson conducted a series of tests on the shroud, including X-rays and chemical analyses. They concluded it was not painted, dyed or stained and that the bloodstains were real. But those findings did little to quell the controversy.

Many believe Jesus imprinted his image on his burial cloth during his Resurrection, and others think the shroud is the authentic burial cloth but that the image was formed by natural processes. Skeptics maintain that the shroud is a forgery created by a medieval artist seeking to display it to relic-hungry pilgrims.

Doctorate in physics

Jackson, a former professor at the Air Force Academy, holds a doctorate in physics from the U.S. Naval Postgraduate School. Born and raised in Denver, he also is a Catholic who has been transfixed by the shroud since he first saw its image at age 13.

His faith isn't incompatible with his scientific training, he said. "How I think about the shroud comes from the shroud. It's not, 'Gee, I'm a Christian, so I'll force it to be what I want it to be.' "

His wife is a relative newcomer to the pursuit.

Raised in Brooklyn, Rebecca Jackson, 60, was 34 when she decided to enlist in the Army and ended up at Fort Carson, near Colorado Springs, as a cook.

In 1990, she was watching a documentary on the shroud when it occurred to her that the image of the man's face looked like her grandfather's. She tracked down Jackson, who had appeared in the film and lived in Colorado Springs, to talk about her reaction. Their shared interest led to a relationship. Her religious conversion followed.

Twice a week, John Jackson works with a team of volunteer researchers in his Colorado Springs laboratory.

Stretched across one wall is a life-size photo of the shroud; on a table is the Styrofoam figure of a man, dubbed Roger, an approximation of Jesus' body in his tomb. Jackson has conducted research on the shroud's crease marks, image formation and how blood flows from a crucified body, which he studied by suspending his own body from a cross.

Keith Propp, 55, has worked with Jackson for 23 years. "It's like we're on an archaeological expedition that's not finished. I'm not sure we'll ever be truly finished. A lot of the pleasure is in the journey itself," he said.