At 45 feet 1.5 inches in diameter, Eartha is credited by the Guinness Book of World Records as the "World's Largest Revolving/Rotating Globe," and will likely take the title of largest globe when it supersedes the "Globe of Peace" in Apecchi, Italy, which measures 33 feet in diameter.
Designed by David DeLorme, namesake (and CEO) of the DeLorme tech company, Eartha is located on the DeLorme campus in Yarmouth, Maine. Designed completely digitally, it is the composite of multiple sources including satellite data, detailed bathymetry, and urban maps. The DeLorme website claims that the data is equivalent to approximately 140 gigabytes, making it the largest composite image of the Earth ever assembled.
The globe itself is at a 1:1,000,000 scale, which works out to about an inch per sixteen miles. It is tilted properly at 23.5 degrees, and moves under the power of two specially designed computer-controlled motors at a maximum speed of one rotation every minute. The skin of the globe is comprised of 792 sections each spanning a distance of 8° latitude by 10° longitude. These are mounted on and supported by DeLorme's proprietary "Omni-Span™ Truss structure," i.e. over 6,000 pieces of aluminium tubing.
Interesting Facts on the Eartha website:
More Info:
http://www.delorme.com/companyinfo/eartha.htm
Image:
http://www.delorme.com/companyinfo/images/eartha_inside.jpg