What is the composition of the Moon, and how does it compare to the composition of Earth? How might a crater made by the impact of a comet with the Moon differ from a crater made by the impact of an a...What is the composition of the Moon, and how does it compare to the composition of Earth? How might a crater made by the impact of a comet with the Moon differ from a crater made by the impact of an asteroid? After looking over the information in Earth, Moon, and Sky and this chapter about the motions of the Moon, can you explain why? (It helps to draw a diagram for yourself.)