Composite enhanced color images of Pluto (bottom right) and its moon Charon (top left), taken by NASA’s New Horizons in 2015.
The New Horizons mission has revealed many new insights about Pluto and its system. This composite of enhanced color images of Pluto (bottom right) and its moon, Charon (top left), was taken by NASA’s New Horizons spacecraft as it passed through the Pluto system on 14 July 2015. Pluto and Charon are shown with approximately correct relative sizes, but their true separation is not to scale. The image combines blue, red, and infrared images taken by the spacecraft’s Ralph/Multispectral Visual Imaging Camera. Credit: NASA/JHUAPL/SwRI

A new page-turner out today provides a detailed insider’s view of the dramatic scientific and political twists and turns of the New Horizons mission and Pluto flyby. The mission has brought new insights about a previously unexplored world, gained global attention, and is now continuing on to explore its next target in our solar system’s Kuiper Belt.

Chasing New Horizons: Inside the Epic First Mission to Pluto offers an “intimate perspective on the historic journey to conceive, create, and culminate in the exploration of Pluto—the capstone journey in the first reconnaissance of the planets of our solar system,” write coauthors Alan Stern and David Grinspoon. Stern, a planetary scientist, is principal investigator of the New Horizons mission; Grinspoon, a planetary scientist and also a writer by trade, witnessed some of the key moments of the mission and helped with public outreach for the flyby.

The book colorfully traces the adventure of making the mission happen from its inception—a May 1989 dinner gathering of some planetary scientists following the first-ever scientific session on Pluto held at a meeting of the American Geophysical Union, which publishes Eos—through the Pluto flyby and beyond.

The authors tell the story about efforts along the way to build up interest and momentum for the mission and political battles to keep it on track. They discuss the scientific justifications for the flyby that became a top planetary science priority for NASA, efforts by the talented science team at the Johns Hopkins University’s Applied Physics Laboratory and others to make the mission happen, and, of course, the elephant in every Pluto-focused room: the vote to demote Pluto as a planet at a 2006 meeting of the International Astronomical Union (IAU).

Near-Death Experiences and Mission Highs

“If [New Horizons] had been a cat, it would have been dead long ago. A cat only has 9 lives; we had about 12.”

The mission had to launch between 2002 and 2006 to take advantage of a Jupiter gravity assist, and it had to reach its destination before the 2020s so that Pluto would still be in a suitable location along its orbit to study as fully as possible. However, in getting to those goals, the mission had many near-death experiences, which Stern and Grinspoon detail in the book.

Among those near-death experiences were pushes to maintain funding, competition against other proposals, a near-catastrophic computer glitch that forced the science team to race against time to reupload vital code to the spacecraft just before the critical flyby window, and enough worry about potentially lethal debris near Pluto that the science team made a fail-safe data transmission part of the plan for the spacecraft.

“If [New Horizons] had been a cat, it would have been dead long ago. A cat only has 9 lives; we had about 12,” Stern told Eos in a recent interview about the mission and the book.

But those obstacles were far outweighed by the mission’s highlights, including the 19 January 2006 launch of New Horizons. The book captures all the drama of that scene: Thirty seconds before liftoff, Stern rushed from the control center to an outside balcony to witness the launch live instead of on a monitor.

The undisputed mission highlight is all the data about Pluto and its system that New Horizons transmitted billions of kilometers back to Earth, including “that jaw-dropping, fail-safe image of Pluto,” as Stern relays in the book. That’s an image of Pluto taken on 13 July, the day before closest approach, showing a large heart-shaped surface feature.

The science team, which had worked on executing the mission for so long, was thrilled that “it turned out so well in that one moment,” Stern told Eos. “It’s like the finish of a Super Bowl almost. You know, a last minute save in overtime. It’s that kind of experience.”

Reflecting on the Mission’s Accomplishments

The mission “showed how captivating raw exploration is,” Stern said. “We’d almost forgotten what that was like because it had been so long since Voyager.”

Stern, in the interview, said the mission has “revolutionized” our understanding of small planets. “Scientifically speaking, the fact that small planets can be as complex as big ones is a big headline,” he said. “The second headline was we were very surprised by the degree of geologic activity on a massive scale that’s taking place today on Pluto.”

The mission “showed how captivating raw exploration is,” he continued. “We’d almost forgotten what that was like because it had been so long since Voyager,” NASA’s two spacecraft that explored the outer solar system decades earlier.

The day of the flyby, NASA’s websites received more than one billion hits, and Stern said that even now, 3 years later, the public is enamored of the mission. Stern told Eos that people tell him and other science team members that the mission changed their lives, the way they look at science, or their children’s perspective on what they want to do for a living.

New Horizons principal investigator Alan Stern of the Southwest Research Institute, center, along with other team members, reacts as he views new images from the New Horizons spacecraft for the first time on 15 July 2015 at the Johns Hopkins University’s Applied Physics Laboratory in Laurel, Md. Credit: NASA/Bill Ingalls

“I don’t think we expected that kind of emotional public attachment,” he added. “I think it was a mélange of first-time exploration, a little bit of risk, a near-death experience, a team that had been underdogs for a long time.” And it was a nail-biter to the very end, Stern continued. “Opening night was also closing night as the one and only shot we had.”

New Horizons was billed as “the first mission to the last planet,” and Stern said he still considers Pluto a planet, despite the IAU vote. The vote was decided “mostly by people who don’t work on planets,” he told Eos. “I don’t think the public ever really bought it. That’s why today you still hear this story as a controversy. And certainly in the planetary science community, I don’t think that we really know what to call a world like Pluto except a planet.”

The next exploration target for New Horizons is Ultima Thule, a Kuiper Belt object (KBO) officially known as MU 2019 that is more than 1.5 billion kilometers beyond Pluto. The spacecraft is on course to zoom past Ultima Thule from a distance of about 3,000 kilometers on 1 January. Plans also call for New Horizons to study about two dozen other KBOs from afar.

Grit, Gumption, and Persistence

Stern told Eos that a key lesson from New Horizons is that persistence pays off. “Young scientists, or young perspective scientists: expect it to be hard, develop your persistence skills alongside your technical skills. And if it’s important, if you think that the science is important, go to the mat for it, make it happen no matter what happens,” he advised.

“You see in so many scientific enterprises, whether it’s the study of climate change or the exploration of the solar system, that it takes real grit and gumption and persistence to do this kind of science,” he stated. “But as we showed with New Horizons, and as I hope the book Chasing New Horizons shows, the reward is so amazing that it makes all of that worth it.”

—Randy Showstack (@RandyShowstack), Staff Writer


Showstack, R. (2018), New book conveys details and flavor of first mission to Pluto, Eos, 99, Published on 01 May 2018.

Text © 2018. The authors. CC BY-NC-ND 3.0
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