Describes the orbit, rotation, temperature, and surface formations of the planet Mercury and the probe Mariner X that took pictures of it in 1974 and 1975.
Describes the planet Earth, exploring its composition, early ideas about its shape and position in the solar system, current theories about its creation, and its important relationship with the moon.
Examines the physical characteristics and conditions of Saturn, describing its position in relation to the sun and other planets and surveying humanity's attempts to penetrate its mysteries.