I endorse Jim Bell’s The Interstellar Age as an accessible and enjoyable read. He explores the unfolding story of the Voyager probes that expanded human knowledge of the outer solar system. He was there for some of it as a Caltech student running errands for mission scientists at JPL when the twin spacecraft flew by our four outer planets and their retinues of moons.
Professor Bell is also president of the Planetary Society, and as expected, his charming and positive attitude about space exploration and a crisp writing style keeps this book rolling along nicely. A plus are some personal anecdotes about the scientists.
Other books cover more of the backstory of these missions, but this volume devotes time to the what-ifs of the future. Makes you think: should we have included messages to aliens on these probes, telling them exactly where to find us? A few people in the 70’s thought no.
A brief NPR interview with Professor Bell is here.