Desktop Planetarium and Charting

International Outer Planet Watch International Outer Planet Watch- A program to study the time variability of the outer planets. Planet Facts Planet Facts- Provides photographs and information about each planet in the solar system. Definition of Planet - Wikipedia Definition of Planet - Wikipedia- Article describes the history and present controversy surrounding the word and its applicability to various objects. Welcome to the Planets Welcome to the Planets- Images from NASA's planetary exploration program.