The story of Noah's ark is found in the Bible's Book of Genesis. It says God saw how corrupt the Earth had become and decided to "bring floodwaters to destroy all life under the heavens."
God reportedly told Noah to preserve life on Earth by building an ark and filling it with two of every species on the planet. The rains unleashed by God are said to have lasted for 40 days and 40 nights. The Bible says that water came from under the Earth as well. When the waters receded, the ark landed in the region of Mount Ararat, according to the biblical account.
Reports of ark sightings have been common. Witnesses have described an old wooden structure sticking out of the snow and ice near the summit of Mount Ararat, which is located in Turkey near its border with Armenia and Iran.
Because of Soviet complaints that explorers were spying, the region was off limits until 1982. Since then, scores of climbers have scaled the mountain but failed to substantiate what the object is.
In 1997 the U.S. government released images taken by its Air Force in 1949 that were believed by some to show a structure covered by ice on Mount Ararat. These photographs had reportedly been kept in a government file labeled "Ararat Anomaly." However, experts deemed the images inconclusive.
While no scientific evidence of the ark's existence has emerged, the Turkish government has reportedly documented cases of expeditions bringing wood up to Mount Ararat and "finding" it the next year.
In the CBS documentary, The Incredible Discovery of Noah's Ark, a man named George Jammal displayed what he claimed to be an ancient piece of wood from inside the ark. Jammal, an Israeli actor living at the time in Long Beach, California, later said the wood was actually from some railroad tracks in Long Beach. He admitted he had never set foot in Turkey.
The documentary also dramatized a 1989 solo expedition by Ahmet Ali Arslan in which he claims to have come within 200 feet (60 yards) of the ark and photographed it. But experts have questioned the authenticity of the photos and Arslan's story.
"Ahmet is a big talker," said one well-known ark researcher, who asked that his name be withheld so as not to jeopardize his own chances of obtaining an expedition permit from the Turkish authorities. "In one conversation he will say that he has 3,000 photos, and in another conversation ten minutes later 5,000 photos."
For years, attempts by McGivern to have satellite images taken of Mount Ararat failed. In the summer of 2003 he recruited DigitalGlobe, a commercial satellite-imagery firm, to try again. This time, a heat wave that hit Europe that year had partially melted the snowcap on top of the mountain.
McGivern claimed the new images showed a large structure, with vertical beams and one horizontal beam, buried on the mountain. He said he was 98 percent sure it was the ark.
Most experts, however, were skeptical. The object in the images could easily be a rock formation, they said, adding that some of the photos were nonscientific and fuzzy.
"It's very easy to get something that looks like it's man-made [in these images]. But once you get there, it turns out to be nothing," said Lorence Collins, a retired geology professor at California State University at Northridge and an expert on photo-geology. "It's simply hopeful thinking."
WorldNetDaily.com, a politically conservative Web site that often reports religious news, quoted McGivern: "The government of Turkey did not issue a research visa, which is sad, but it's their country. We haven't totally given up, but it's pretty obvious they're not going to give us one."
If Noah's ark exists, could it be buried on Mount Ararat? That depends on whether the flood actually happened.
Some Christians were encouraged by a theory advanced by Walter Pitman and William Ryan, two geology professors at Columbia University in New York. The researchers suggested that a great deluge at the end of the last ice age, 8,400 years ago, caused the Aegean Sea to overflow into the Black Sea.
However, other geologists argue the Black Sea was already full by the time Noah is said to have sailed off on his ark. They say a much slower rise in the sea level occurred up to 12,000 years ago, as the glaciers melted.
"Evidence [instead] points conclusively to strong outflow from the Black Sea basin into the Mediterranean through the intervening Marmara Sea since about 11,000 years ago," said Richard Hiscott, a professor of earth sciences at Memorial University in St. John, Canada.
Most geologists seem to agree that it would probably be impossible for a ship to make landfall at an altitude of 15,000 feet (4,570 meters). (Some explorers claim the ark is buried elsewhere, noting the Bible talks about several mountains.)
Cline, the George Washington University historian and archaeologist, calls the Noah's ark expeditions "fringe archaeology."
"Speaking strictly for myself," he said, "I am happy to stay out of such an area of debatable research."
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