SPHERES OF THE HEAVENS - Celestial Globes

Celestial Globe, Isfahan (?), Iran 1144. Shown at the Louvre Museum, this globe is the 3rd oldest surviving in the world

Giuseppe de Rossi Celestial globe, Venice, Museo Correr

Long before there were planetariums or advanced technologies available for studying the sky, people devised ways of depicting the sun, moon, planets, and stars in relation to the Earth. There was a desire to learn about astronomical history and events; people wanted to figure out how Earth fit into the grand scheme of the universe. Globes helped to put objects into perspective, and served as scientific instruments, ornamental showpieces, and physical illustrations of the astronomy beliefs of the day.

Globes have been visual representations of the physical characteristics of Earth and Sky for thousands of years

Celestial Globe at The Franklin Institute

. Generally, there are three types of globes. Terrestrial globes detail geographical features of the Earth. There are also globes that illustrate the physical features of celestial bodies, such as the moon or Mars. Celestial globes, like the one pictured here, are spherical maps of the sky—models of the visible heavens.

There is written evidence that proves that the ancient world was familiar with the scientific principles necessary for depicting the celestial and terrestrial spheres, and the oldest known surviving ancient globe is the Farnese Atlas, now at the National Museum of Naples. The Farnese Atlas is a decorative celestial globe, about 25 inches in diameter, that shows the outline of constellations against a coordinate system. The statue of Atlas is dated 73 B.C.; the position of the constellation figures to the globe's equinox date the globe itself to around 370 B.C. (Naturally, the ancient globes and models were representative of the astronomical ideas held at that period of time.)

Astronomy is one of the longest-studied sciences in history. Scientists have attempted to answer questions that seem far beyond our understanding for centuries. As long as we wonder about heavenly objects, some will try to recreate the nighttime sky with instruments such as the globe, lighting the world as the stars themselves do with their ideas, models, and theories.

Reference: Instruments of Science: An Historical Encyclopedia New York & London, 1998.