Zlatko Moon: Eartha: World's Largest Rotating Globe

The world's largest rotating globe, nicknamed "Eartha", is located at the headquarters of DeLorme, a business that provides mapping products, which is in Yarmouth, Maine, the United States, about 15 minutes north of Portland.

The globe is enormous — 41 feet in diameter and weighs 2,500 kg, so big that you need to take the stairs to the second or third floor to see the northern hemisphere. In 1999 the Guinness Book of World Records confirmed it was the largest globe to be ever made, beating the previous title holder, the Globe of Peace, located in Pesaro, Italy, by more than 9 feet. The globe is housed inside a three-story glass atrium which is beautifully illuminated at night and readily visible from U.S. Route 1.

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Eartha was unveiled in 1998 and took two years to complete. It was built at a scale of 1:1 million, meaning that one millimeter on its surface corresponds to one kilometer on Earth's surface. That allowed the builders to put great deal of details such as road networks and urban areas, as well as relief and ocean depth info. The database used to generate the surface images was approximately 140 gigabytes. That was a big thing back in 1998. Google Maps wasn’t invented then.

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The globe is built on a skeleton of over 6000 pieces of aluminum tubing which is covered by a skin of 792 map panels. As with most globes, its mounted at a 23.5 degree angle, the same axial tilt as the Earth itself. The equator is thus diagonal to the floor. It uses a cantilever mount with two motors, that slowly rotates the globe completing one rotation in about 18 minutes, but it can be sped up to fully rotate the globe in as little as one minute or slowed down to an hour.