Topography globe featuring physical features of the Earth
Aglobe is asphericalmodel ofEarth, of some othercelestial body, or of thecelestial sphere. Globes serve purposes similar tomaps, but, unlike maps, they do not distort the surface that they portray except to scale it down. A model globe of Earth is called aterrestrial globe. A model globe of the celestial sphere is called acelestial globe.
A globe shows details of its subject. A terrestrial globe showslandmasses andwater bodies. It might show nations and major cities and the network oflatitude and longitude lines. Some have raisedrelief to show mountains and other large landforms. A celestial globe shows notable stars, and may also show positions of other prominent astronomical objects. Typically, it will also divide the celestial sphere intoconstellations.
The wordglobe comes from theLatin wordglobus, meaning "sphere". Globes have a long history. The first known mention of a globe is fromStrabo, describingthe Globe of Crates from about 150 BC. The oldest surviving terrestrial globe is theErdapfel, made byMartin Behaim in 1492. The oldest surviving celestial globe sits atop theFarnese Atlas, carved in the 2nd centuryRoman Empire.
Students and teacher looking at a terrestrial globe of the earth.
Flat maps are created using amap projection that inevitably introduces an increasing amount of distortion the larger the area that the map shows. A globe is the only representation of the Earth that does not distort either the shape or the size of large features – land masses, bodies of water, etc.
TheEarth's circumference is quite close to 40 million metres.[1][2] Many globes are made with a circumference of one metre, so they are models of the Earth at a scale of 1:40 million. In imperial units, many globes are made with adiameter of one foot[citation needed] (about 30 cm), yielding a circumference of 3.14 feet (about 96 cm) and a scale of 1:42 million. Globes are also made in many other sizes.
Some globes have surface texture showingtopography orbathymetry. In these, elevations and depressions are purposely exaggerated, as they otherwise would be hardly visible. For example, one manufacturer produces a three dimensional raised relief globe with a 64 cm (25 in) diameter (equivalent to a 200 cm circumference, or approximately a scale of 1:20 million) showing the highest mountains as over 2.5 cm (1 in) tall, which is about 57 times higher than the correct scale ofMount Everest.[3][4]
Most modern globes are also imprinted withparallels andmeridians, so that one can tell the approximatecoordinates of a specific location. Globes may also show the boundaries of countries and their names.
Many terrestrial globes have one celestial feature marked on them: a diagram called theanalemma, which shows the apparent motion of the Sun in the sky during a year.
Globes generally show north at the top, but many globes allow the axis to be swiveled so that southern portions can be viewed conveniently. This capability also permits exploring the Earth from different orientations to help counter thenorth-up bias caused by conventional map presentation.
Celestial globes depict star positions while excluding the Sun, Moon, and planets due to their variable locations, though they mark the ecliptic—the Sun’s apparent path. A structural challenge arises from the difference between Earth’s perspective (a gnomonic projection from the celestial sphere’s center) and the globe’s external orthographic projection, which reverses constellations. Transparent globes introduce distortions when viewed externally, whereas opaque versions with reversed constellations and text are designed for mirror reflection to restore correct orientation.[5]
Historically, celestial globes reflected geocentric models, such as Ptolemy’s 2nd-century system using epicycles and equants to explain planetary motion. Medieval astronomers, influenced by his work, constructed globes to model star arrangements under the assumption of a static Earth encircled by rotating celestial spheres. This framework persisted until Copernicus proposed a heliocentric system, redefining humanity’s understanding of cosmic structure.[6]
No terrestrial globes from Antiquity have survived. An example of a survivingcelestial globe is part of a Hellenistic sculpture, called theFarnese Atlas, surviving in a 2nd-century AD Roman copy in theNaples Archaeological Museum, Italy.[10]
Early terrestrial globes depicting the entirety of theOld World were constructed in theIslamic world.[11][12] During the Middle Ages in Christian Europe, while there are writings alluding to the idea that the earth was spherical, no known attempts at making a globe took place before the fifteenth century.[13] The earliest extant terrestrial globe was made in 1492 byMartin Behaim (1459–1537) with help from the painter Georg Glockendon.[10] Behaim was a German mapmaker, navigator, and merchant. Working inNuremberg, Germany, he called his globe the "Nürnberg Terrestrial Globe." It is now known as theErdapfel. Before constructing the globe, Behaim had traveled extensively. He sojourned inLisbon from 1480, developing commercial interests and mingling with explorers and scientists. He began to construct his globe after his return to Nürnberg in 1490.
China made many mapping advancements such as sophisticated land surveys and the invention of the magnetic compass. However, no record of terrestrial globes in China exists until a globe was introduced by thePersian astronomer,Jamal ad-Din, in 1276.[14]
Another early globe, theHunt–Lenox Globe, ca. 1510, is thought to be the source of the phraseHic Sunt Dracones, or "Here be dragons". A similargrapefruit-sized globe made from two halves of anostrich egg was found in 2012 and is believed to date from 1504. It may be the oldest globe to show theNew World. Stefaan Missine, who analyzed the globe for the Washington Map Society journalPortolan, said it was "part of an important European collection for decades."[15] After a year of research in which he consulted many experts, Missine concluded the Hunt–Lenox Globe was acoppercast of the egg globe.[15]
Globus IMP, electro-mechanical devices including five-inch globes have been used in Soviet and Russian spacecraft from 1961 to 2002 as navigation instruments. In 2001, theTMA version of theSoyuz spacecraft replaced this instrument with adigital map.[18]
A short, 1955 Dutch film showing the traditional manufacture of globes using paper gores
Traditionally, globes were manufactured by gluing a printed paper map onto a sphere, often made from wood.[19]
The most common type has long, thingores (strips) of paper that narrow to a point at the poles,[20] small disks cover over the inevitable irregularities at these points. The more gores there are, the less stretching and crumpling is required to make the paper map fit the sphere. This method of globe making was illustrated in 1802 in an engraving in The English Encyclopedia by George Kearsley.
Modern globes are often made fromthermoplastic. Flat, plastic disks are printed with a distorted map of one of the Earth'shemispheres. This is placed in a machine which molds the disk into a hemispherical shape. The hemisphere is united with its opposite counterpart to form a complete globe.
Usually a globe is mounted so that its rotation axis is 23.5° (0.41rad) from vertical, which is the angle the Earth's rotation axis deviates from perpendicular to the plane of its orbit. This mounting makes it easy to visualize howseasons change.
In the 1800s small pocket globes (less than 3 inches) were status symbols for gentlemen and educational toys for rich children.[21]
TheUnisphere inFlushing Meadows, New York, at the Billie Jean King USTA Tennis Center, at 37 m (120 ft) in diameter, is the world's largest geographical globe. This corresponds to a scale of about 1:350 000. (There are larger spherical structures, such as theCinesphere inToronto, Ontario, Canada, but this does not have geographical or astronomical markings.)
Wyld's Great Globe, located in London'sLeicester Square from 1851-1862, was a hollow globe 60 feet 4 inches (18.39 m) in diameter designed by mapmakerJames Wyld. Visitors could climb stairs to view a plaster of Paris model of the Earth's surface, complete with mountains and rivers to scale.
Eartha, the world's largest rotating globe with a diameter of 12 m (41 ft), located at theDeLorme headquarters inYarmouth, Maine. This corresponds to a scale of about 1:1.1 million. Eartha was constructed in 1998.
TheP-I Globe, a 13.5-ton 30-foot (9.1 m) neon globe with rotating "It's in the P-I" words and an 18-foot eagle, was made in 1948 for theSeattle Post-Intelligencer's headquarters. It was moved to the newspaper's new location in 1986.
TheGreat Globe at Swanage is a stone sphere that stands atDurlston Castle withinDurlston Country Park,England. Measuring 10 feet (3.0 m) in diameter and weighing 40 tons, this intricately carved globe showcases the continents, oceans, and specific regions of the world. Crafted from Portland stone, it spans about 3 meters (10 ft) in diameter.
^The Earth’s circumference is 40 million m because themetre was originally defined to be one 10-millionth of the distance between the poles and the equator.
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