When I was born, Voyager 1 had been snapping pictures of Jupiter for about a month. Three weeks later, the spacecraft made its closest approach to the gas giant. Within three months, the bus-sized craft was flying away from our solar system’s largest planet, on its way to further planets, deep space and the last reaches of our sun’s solar winds.

The probe — along with its twin, Voyager 2 — is the subject of environmental historian Stephen J. Pyne’s latest book, Voyager. Launched in 1977, just eight years after humans first landed on the moon, the probes were to give a “grand tour” of the solar system, shooting back images of Jupiter, Saturn, Uranus and Neptune.

But what they truly did, Pyne argues, is define and symbolize the third age of exploration, the first launched by Portuguese seaman (and perhaps symbolized by the “discovery” of the New World), and the second by Enlightenment-fueled cataloguers like Charles Darwin.

Mixing fact with historical perspective, Pyne deftly explains how circumstance and coincidence led to the improbable launch of the Voyager crafts. (Surprisingly, the alignment of the planets that allowed for the tour only comes along once every 176 years. The next window will be 2153.) This, along with the evolution of rocketry and computer science, made possible what even 20 years earlier would have been pure fantasy.

For the astronomy- or history-minded, this book is great fun.

Hearing about all the ways in which the mission was almost killed — and about all the people involved in its success — is in itself a grand tour of 1960s and ‘70s bureaucracy and politics. And Pyne’s articulation of spaceflight is unbeatable.

But for the less interested, the 400-page book might be a bore. And the scant, low-quality photo pages are frustrating. Where are the beautiful color photos of Jupiter? The close-up shots of Saturn’s rings?

Still, this scientific book is poetic. Going 38,000 miles per hour, the first Voyager is more than 10 billion miles from home and still moving. And as Walt Whitman wrote, “Now, Voyager, sail thou forth, to seek and find.”