Planet Trek: Mapping New Worlds

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Part II: Concept Introduction: Features

Activity # 4 - Nomenclature

What is nomenclature?

"Nomenclature" means a system for naming things. And just like on Earth where mountains, rivers and other features are named, surface features on other worlds are also named. Since 1919 the International Astronomical Union has been responsible for the naming of these features.

How are surface features named?

A theme is usually chosen for each world as detailed images are obtained by the IAU. First, important features are given a name, then as additional features are observed through better digital imagery, names are suggested by the scientists investigating that world.

What are the "Rules" for Naming new discoveries?

From the USGS Nomenclature site, these rules include:

• Nomenclature is a tool and the first consideration should be to make it simple, clear, and unambiguous.
• Duplication of the same name on two or more bodies is to be avoided.
• Individual names chosen for each body should be expressed in the language of origin.
• Where possible, the themes established in early solar system nomenclature should be used and expanded on.
• Solar system nomenclature should be international in its choice of names.
• No names having political, military or religious significance may be used, except for names of political figures prior to the 19th century.
• Commemoration of persons on planetary bodies should be reserved for persons of high and enduring international standing. Persons being so honored must have been deceased for at least three years.

What are some of the themes use?

• Jupiter's satellites are named after mythical loves of Zeus
• The moons of Uranus are Shakespearean women and faeries
• The features on the surface of Venus are all named after famous women
• The craters on the Moon are named for famous scientists in history

Look at the information in the tables below. Can you identify the theme used for these features on each world?

Use an encyclopedia or other reference source to find clues to help you complete the table by identifying the theme for these features:

All feature descriptions are from the USGS Nomenclature Website. These are listed under "Section 1: Names listed by planetary system, satellite, and feature type." Each planetary system is linked here with a complete nomenclature including feature type, name, origin and latitude/longitude coordinates. When you complete this activity, you might enjoy exploring this website to see what other themes have been used in naming the surface features on the various worlds of our solar system. The USGS Planetary Categories page can provide information on the themes used in naming features on various worlds.

When you have completed this activity, you can check the ANSWER KEY.