Wednesday, July 24, 2019, 9:00-10:00 p.m.

The four planets closest to the sun, known as the rocky planets, were born around the same time and from the same material. Yet today they are shockingly different. Tiny Mercury, with its outsize metallic core, swiftly orbits the sun almost like a moon. Venus is a devilishly hot world with a crushing atmosphere. Mars is a dusty, red desert world marked by the remnants of rivers and waterfalls. And then there’s Earth, with the perfect conditions for life to thrive. But why only here? And how long will it last? NOVA takes you on a dramatic journey through space and time to discover how the fates of the rocky planets diverged, and what it might take for life to arise somewhere else. It may be that the next host of life in our solar system isn’t a neighbor at all, but a distant moon of Saturn.