What do inner planets have in common?
What do inner planets have in common? All of the inner planets are solid, dense, rocky planets. The inner planets either do not have moons or have just one (Earth) or two (Mars). None of the inner planets have rings. Compared to the outer planets, the inner planets have shorter orbits around the Sun, but all the inner planets spin more slowly. What do all 4 of the inner planets have in common? The four planets closest to the Sun - Mercury, Venus, Earth, and Mars - are the inner planets. They are similar to Earth. All are solid, dense,...