Here is the last book in the "space quartet", Beyond Mars. It takes a large survey of the next steps in space including: solar sailing, travel to Saturn via long distance trips to the outer solar system, multi-year hibernation travel, hydroponics, and visiting other solar systems.
Nephew, William and Michael Chester. Illustrated by Buehr, Walter. Beyond Mars. New York: G. P. Putnam’s Sons. (72 p.) 1960.