By Cosmic Log

A laser scanning team has just finished up work on Mount Rushmore, kicking off the latest phase of a project to create a digital record of the world’s great monuments. Two weeks of arduous 3-D scanning wrapped up just today, said Elizabeth Lee, director of projects and development for California-based CyArk. "It was a really successful project," she told me. But it wasn't without its challenges. Rope teams had to clamber down the face of the mountainside in South Dakota's Black Hills to record the ins and outs of the 60-foot-long presidential faces. The weather didn't help. "We had everything," Lee said. "We had 90-degree heat, where people got sunburned. We had snow that kept us from working for two days. Yesterday, there were hailstorms and floods and tornadoes." But it's all worth it: When all the readings are compiled, the partners in the project - including the National Park Service - will have the most accurate virtual rendering ever made of the decades-old monument. Between 1927 and 1941, the faces of Presidents George Washington, Thomas Jefferson, Abraham Lincoln and Theodore Roosevelt were sculpted by hundreds of workers using dynamite and chisels. This time around, the workers had to take care not to chip away at the rock. In addition to using more traditional surveying techniques, Lee and her teammates set up laser-scanning equipment on custom-made tripods, and bounced laser light harmlessly off the sculpture's nooks and crannies. CyArk explains how laser scanning works in detail.

Laser scanners capture millions of data points to create a high-resolution rendering of Abraham Lincoln's face. (Photo by Kacyra Family Foundation / CyArk)

During today's final round of measurements, a tripod was positioned on Washington's eyebrow and just above his chin to scan the parts of the face that couldn't be accurately measured from the ground or from the top of George's head, Lee said. The product of all this work will be a high-definition 3-D computer representation of the famous faces. The park service can use the database to create picture-perfect representations of Mount Rushmore for scale models, online virtual tours and perhaps a holographic display at the visitor center. And in case anything happens to the monument - ranging from normal wear and tear to a catastrophic crumbling - the 3-D data can be used to guide repairs. CyArk sees the Rushmore project as part of its grand plan is to create virtual records for 500 heritage sites around the world in five years. "We haven't set an official start date yet," Lee said. Nevertheless, the venture is getting an early start toward the 500-site goal by carrying out more than 30 preservation projects at places ranging from Angkor Wat to the ancient Egyptian capital of Thebes to San Francisco's Presidio. Lee said CyArk is the brainchild of engineer/entrepreneur Ben Kacyra, who immigrated to the United States from Iraq in 1964 and helped develop the 3-D laser-scanning technology that was used on Mount Rushmore. In the past, laser scanning has been put to use in such applications as "Star Wars" anti-missile systems and oil-prospecting operations. Kacyra is using some of his fortune to show that "the technology that he developed could be used for heritage purposes" as well, Lee said. In an Associated Press interview, Kacyra said he was pleased to see Rushmore added to the laser-scan list. "Being an immigrant, the monument is a symbol that I cherish," he said. "It's a symbol for the U.S., and a symbol for the world." Rushmore was CyArk's first international project done in collaboration with the "Scottish 10," a heritage-mapping effort that involves Historic Scotland and Glasgow School of Art. There are still more groups out there scanning history. Here are just a few of the latest adventures to come to light:

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Cosmic Log