Coordinate System
A crater named Anat provides the reference point for measuring longitude on Ganymede. By definition, Anat is at 128 degrees longitude.
Read more about this topic: Ganymede (moon)
Famous quotes containing the word system:
“Hence, a generative grammar must be a system of rules that can iterate to generate an indefinitely large number of structures. This system of rules can be analyzed into the three major components of a generative grammar: the syntactic, phonological, and semantic components.”
—Noam Chomsky (b. 1928)