The Solar System

When we think of maps, we usually think of some section of the Earth being represented in a two-dimensional form. These maps can be informative, decorative, or intended to assist in navigation - or some combination of the three. Most of the maps in the Virginia Garrett Cartographic History Library fit that definition!

Astronomers have always known that the planets of our Solar System were different from the stars. The Ancient Greeks called planets planētes asteres, or "wandering stars" since their position in the night sky changed, while the stars remained constant. Until the invention of the telescope in the early 1600s, humanity understood very little about the planets. When Galileo Galilei discovered four moons around Jupiter, for example, he helped overturn thousands of years of science suggesting that the Earth was the center of everything. William Herschel's discovery of Uranus in 1781 marked the first time in thousands of years that humanity discovered a new planet.

As our technology grew, our ability to map the surfaces of planets became possible - and necessary! Cartographers like Cellarius and Doppelmayr added maps of the Moon, showing Jupiter and Saturn's satellites, and depictions of the outer planets showing their shapes. In the 1900s, more precise maps of planetary surfaces were needed as humanity set its sights on exploration. In 1963, the United States established the U.S. Geological Survey's Astrogeology Science Center to map the Moon in support of the Apollo space program. Since then, the Astrogeology Center has created thousands of maps of planetary surfaces throughout our Solar System. Celestial mapping has come a long way - from using our eyes to sending space probes millions of miles from Earth to take detailed pictures that turn into maps.