A thick blanket of atmosphere warms and sustains Earth’s temperate climate. On Venus,
by contrast, a thick, sulfurous atmosphere pushes the planet’s surface temperature beyond
medieval poet Dante Alighieri’s worst descriptions of hell. A thin atmosphere leaves
Mars’s surface unprotected and frozen. In Chapter 8 we compared the surfaces of the
terrestrial planets; in this chapter we will compare their atmospheres. By the conclusion
of this chapter, you should be able to