The Inner Planets

Discover the rocky inner planets! Learn what makes a planet and identify Mercury, Venus, Earth, and Mars.

Planets Overview of the Planets Fill in the blanks. The most recentdefinition of a planet was adopted by the International Astronomical Union in 2006. It says a planet must do three things:It must orbit a star (in our cosmic neighborhood, the Sun). It must be big enough to have enough gravity to force it into a spherical shape. It must be big enough that its gravity cleared away any other objects of a similar size near its orbit around the Sun. The Rocky Planets Watch the video and answer the following questions. What does it mean to be a TERRESTRIAL planet? Sort the following information. Terrestrial Planets solid surface closer to the sun Few satellites No Rings Composed of rock Small iron cores Gas Giants rings farther from the sun no solid surface many moons Known as Jovian Large with a low density Label the inner planets. Earth Venus Mars Mercury