To preserve my objectivity, I have assiduously avoided reading other reviews of Chasing New Horizons: Inside the Epic First Mission to Pluto by Alan Stern and David Grinspoon. But I would bet euros to eclairs* that an online search would reveal at least one review that includes this sentence: “Alan Stern was born to write this story.”
(* My inner editor wouldn’t allow me to use the trite but familiar “dollars to donuts” here.)
That statement is, at best, partially true. Planetary scientist Alan Stern was born to live the New Horizons story, and no one was better positioned to be his co-author of a book about it than his friend and fellow planetary scientist David Grinspoon.
Indeed, the beginning of both Stern’s active life and the Space Age nearly coincide. Paraphrasing his father, the book describes how the quietly gestating Alan “suddenly began kicking, like crazy” when he “had apparently been hearing people talking about the launch of Sputnik [on October 4, 1957], and was clearly impatient to get out and get going to explore space.” Seven weeks later, he made his entrance.
Twelve years after that, having read every book about astronomy and space exploration he could get his hands on, the young Alan watched Walter Cronkite’s coverage of the early Apollo Moon landings and got excited when the newsman held up a detailed NASA flight plan.
“(I)t ran hundreds of pages and was filled with all kinds of detail, with every activity scripted minute by minute,” he told Grinspoon. “I wanted one, because I wanted to know how spaceflight was really planned.”
He wrote to NASA and was undeterred when they responded negatively because he wasn’t an accredited journalist. For a year, he researched wherever he could to produce a 130-page handwritten book about unmanned spacecraft. He sent it to NASA, and was rewarded, not only by getting the flight plans, but also being mentored long-distance by John McLeish, NASA’s chief public affairs officer in Houston.
McLeish clearly recognized two traits that would eventually lead Alan to success in his own spacefaring career, attention to detail and a fierce determination to reach ambitious goals. And what goal could be more ambitious than completing the exploration of the nine known planets?
In the late 1970s and throughout the 1980s, Alan watched two Voyager spacecraft explore the outer planets. Both successfully flew by Jupiter and Saturn. Voyager 2 continued on to Uranus and Neptune, but was headed in the wrong direction for a Pluto encounter. Voyager 1’s mission scientists could have sent their spacecraft on toward Pluto, but they chose instead a trajectory that enabled a detailed exploration of Saturn’s largest moon, Titan, the only solar system moon known to have a substantial atmosphere.
Pluto would have to wait. Alan quickly emerged as the informal leader of a group of determined Plutophiles who recognized that a once-in-two-centuries opportunity would slip away if they waited too long. The problem was due to the planet’s eccentric 248-year orbit. In 1989, it reached perihelion, its closest approach to the Sun, slightly inside the orbit of Neptune.
Every year of waiting to launch a Pluto mission would make the flight longer. Furthermore, in order to achieve the high speed needed to reach Pluto in a short enough time and without excessive fuel, the trajectory would have to include a Jupiter flyby maneuver. If they missed the 2006 window for that flight path, it would be another decade before they could try again and make it more likely that Pluto’s atmosphere would freeze out before the spacecraft could arrive, losing the opportunity to study those gases and obscuring the surface with a snow blanket consisting of mainly solid nitrogen.
We now know that the New Horizons mission achieved that window and sent back images of Pluto and its moons that were far beyond what anyone could have imagined before its launch. Chasing New Horizons, using a thriller-writer’s you-are-there narrative style, takes readers on the adventure of Alan Stern’s and his remarkable team’s lifetimes, from the struggles to get the project approved and funded; to its design, construction, and launch; to its Jupiter encounter followed by extensive periods of never-before tried “hibernation” to save energy; to the loss of signal ten days before the spacecraft’s closest encounter and its nick-of-time recovery and reboot; to the triumph of the flyby and the choice of the next target in the solar system’s “third zone,” the Kuiper Belt.
Chasing New Horizons would be a “great read” if it were fiction. But as a true story, it is impossible to resist. From the Preface to the “Final Discovery” of the Coda and through the Top-Ten Science Discoveries list in the Appendix, this is a book for science readers to savor.