The DeLorme mapping corporation in Yarmouth, Maine, a privately-held, disabled veteran-owned small business, describes itself as “the long-time innovation leader in mapping and GPS solutions for the consumer, professional, and government markets” (source). It is also home to Eartha, the world’s largest rotating and revolving globe.
“Eartha is a 3-dimensional scale model of our earth with mountains and landforms in full 3D that rotates and revolves, simulating the earth’s real movements. Eartha was given the title of “World’s Largest Revolving/Rotating Globe” by the editors of the Guinness Book of World Records in 1999, and still holds that record today. It measures 41.5 ft in diameter. Unveiled July 23, 1998 Eartha took two years to build and represents earth as it is seen from space. It rotates and revolves on a specially designed and built mechanized, cantilever arm.
The official measurements of Eartha were made for Guinness by several independent and licensed surveyors who found the Globe to measure 41 feet, one and one-half inches, slightly less than the rounded figure of 42 feet that was projected by DeLorme staff members. Still, 41′ 1.5″ was more than enough to surpass the former record-holder, the Globe of Peace in Apeccio, Pesaro, Italy (which is 33 feet in diameter and does not revolve or rotate).
Every aspect of Eartha was developed using computer technology. It was designed by founder David DeLorme. and constructed by DeLorme staff members. ‘The building of Eartha was a tremendous challenge for all of us,’ says DeLorme. ‘It will help us make even better maps and will help others envision how we on earth are all connected.’
The mapping data, which took over a year to compile, is completely unique. It is a special composite database built from satellite imagery, shaded relief, colored bathymetry (ocean depth data) and information from terrestrial sources, such as road networks and urban areas. The printed Eartha database is equivalent to about 140 gigabytes (or 214 CD-ROMs), making it one of the largest in the world! Its scale is 1:1,000,000, which works out to be one inch equaling nearly 16 miles. At this scale, California is three and a half feet tall!
Eartha’s ‘skeleton’ is the Omni-Span™ Truss structure – a DeLorme-developed system of over 6,000 pieces of lightweight aluminum tubing. The ‘skin’ is constructed of over 792 map sections, printed on special materials and mounted on lightweight panels. Those panels are then affixed to the structure with a unique bolt system. Each panel spans 8° latitude by 10° longitude.
Eartha tilts at 23.5 degrees, just as the earth does. It revolves on a specially designed cantilever arm and rotates on an axis. This action is powered by two electric-powered motors, which are commanded by a computer. One combined Eartha revolution and rotation occurs every minute at maximum speed” (source).
