Patterns of Motion All planets orbit in the same direction Planets orbit in nearly the same plane (excluding Pluto) Most planets have nearly circular orbits Most planets rotate in the same direction as they orbit the Sun Most moons orbit in the same direction their planet rotates and near its equatorial plane The Sun rotates in the same direction in which the planets orbit the Sun

Categories of Planets Excluding Pluto, planets fall into two classes Terrestrial planets: smaller radius and mass, higher density, solid surface, closer to Sun, warmer, few moons (if any) and no rings Jovian planets: larger radius and mass, lower density, no solid surface, farther from Sun, cooler, many moons and rings