Steven Schafersman, a geologist who maintains a website skeptical about the shroud, dismisses 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. "Ordinary people know this is just a relic."
But others are challenging the radiocarbon date.
At a conference sponsored by the Shroud Science Group at Ohio State University this weekend, the Los Alamos National Laboratory presented findings that the 1988 test results were flawed because the samples tested came from a portion of cloth that may have been added to the shroud during medieval repairs.
The shroud's historical record dates back 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 that the shroud was not painted, dyed or stained and that the blood stains were real. But those findings did little to quell the controversy surrounding the shroud.
Many believe that Jesus imprinted his image on his burial cloth during his resurrection, and others think that 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. The debate often is bitter; each side accuses the other of twisting facts and ignoring evidence that doesn't fit its view.
In this world, Jackson has long been a central figure.
A former professor at the Air Force Academy and scientist at the Air Force Weapons Laboratory, Jackson holds a doctorate in physics from the U.S. Naval Postgraduate School. Born and raised in Denver, he also is a devout Catholic who has been transfixed by the shroud since he first saw its image at age 13.
"If you love Christ, why wouldn't you want to explore the possibility that you have an artifact of his material existence on Earth?" he said, adding that his faith isn't incompatible with his scientific training: "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.' That's not scientific logic."
Whereas Jackson has focused single-mindedly on the shroud for 35 years, his wife is a relative newcomer.
