Chasing New Horizons: Inside Humankind's First Mission to Pluto

by Alan Stern

Think about that for a minute: seventy years earlier, photons of light from the Sun had reflected off Pluto, traveled for four hours and over all those billions of miles to Earth, and passed through a telescope in Flagstaff, Arizona. Those photons created a tiny dot in a plate of photographic emulsion that had caught young Clyde Tombaugh’s eye when he examined that image a few weeks later, revealing the existence of a new, faraway planet. Now some atoms that had been part of Clyde were going to make the journey to that faraway world and then continue on, outward, to leave our solar system for interstellar space and the galaxy beyond. Whatever you believe about life, death, consciousness, and fate, this was surely a unique and wondrous memorial, unlike any other in history.

The ubiquity of New Horizons and Pluto on the web, and the number of people sharing in New Horizons events around the globe, gave this flyby an entirely new kind of feel. The world had changed since Voyager, with so many new forms of communication and participation. Thanks to that, the New Horizons mission felt in many ways like the first truly twenty-first-century planetary encounter. Consider: with Voyager, to participate fully you had to be in just the right place—specifically, at JPL—at just the right time—on flyby day. For New Horizons you didn’t need to be there; the flyby was everywhere simultaneously. The events at APL, the imagery from Pluto—everything that reached Earth—went onto the internet “for all mankind,” as it were.

Twenty-six years had elapsed between that first fateful meeting to discuss the idea of going to Pluto with NASA in May of 1989, and that summer in 2015 when the exploration of Pluto was accomplished. People who were not even born when it started were moved by it in ways that no one had imagined when the quest began. History was made. New knowledge was created. A nation was reminded it can achieve greatness. And a world was reminded that we humans, we Earthlings—really can accomplish amazing things.

If we humans are nothing else, we are an inquisitive and restless species, explorers at heart. For that reason, we’re also optimistic that even humans will one day travel to the Kuiper Belt to explore it in person, making footfall on Pluto and other Kuiper Belt worlds, as we have already done on the Moon and will soon do on Mars, and then no doubt on many other worlds.