Voyager: Exploration, Space, and the Third Great Age of Discovery

by Stephen J. Pyne

  The Second Age had bequeathed a legacy of geographic surfaces that left the solid geography of Earth and the planets obscured by ice, seawater, and gaseous atmospheres. To probe beneath those contours required special sensors and innovative means to get those instruments to the scene. Until then the terrains of ice, abyss, and space were unknowable. Antarctica did not have its perimeter fully mapped until Operations Highjump and Windmill accomplished the task by air in 1946 to 1948, and no one had traversed the continent until the Commonwealth Trans-Antarctic Expedition did so under loose affiliation with IGY. The deep oceans had been sampled but never seen, and only vaguely understood. They were conceived as a geochemical tomb and a geophysical void, a vast sink removed from the dynamics of the planet. As for the solar system, photos of the planets and the larger moons from Earth-based telescopes existed, but the gritty inner planets and gaseous outer ones were the dregs of astronomy, which was far more fascinated by distant pulsars and quasars, white dwarfs and red giants, spiraling nebulae, cosmic rays, dark matter, and traces of the Big Bang.

  The Third Age revolutionized those perceptions. Field-testing had occurred in Antarctica, and then leaped outward, much as the proposed third polar year had bulked up into the International Geophysical Year. It was, J. Tuzo Wilson wrote, “in the Antarctic, which was least known [of ice sheets], that recent efforts have produced the most marked changes in our knowledge.”218

  Before IGY the basics of Antarctica as a continent were barely appreciated: the pastiche of ice shelves and sheets, the underlying solid-earth surfaces so different between East and West Antarctica, the interconnections of south polar weather with the rest of Earth. Modern technology such as Sno-Cats and DC-4s, seismic profiling, and remote-sensing instruments gradually unveiled the nearly extraterrestrial world that was the Ice. It became both more familiar and more alien. Unlike abyss and space, this was a place where people could walk, breathe, and, along its edges, survive by hunting. With permanent bases established under the aegis of IGY, Antarctic discovery made the transition from exploration to a normal, if extreme science. It made a suitable point of intellectual departure for the discovery of those new worlds, now being exposed, where humanity could not live and would not go.

  The deep oceans were, at the dawn of the Third Age, a deep mystery. A century after Maury had synthesized the known ocean in his Physical Geography of the Sea, Rachel Carson summarized the state of knowledge in her prize-winning The Sea Around Us (1951). Maury’s geography appeared two decades before the Challenger expedition; Carson’s, two decades before the revolution in earth science was distilled into the theory of plate tectonics. If her book was prophetic, it was because she believed that Earth’s seas, its collective Oceanus, were the grand synthesizer of geology, climate, and life, “the beginning and end”; for “all,” she insisted, “at last return to the sea.” Besides, she intoned, it is “always the unseen that most deeply stirs our imagination.” Her prophecy was based on an aesthetic sense. The real revolution came with hard data. 219

  A decade later, as Carson revised and reissued the book, Wilson published his personal account of IGY as viewed from the perspective of his tenure as president of the International Union of Geodesy and Geophysics. “The history of the exploration of the sea floors is brief and simple,” he observed. Not until IGY was their study “first faced in an adequate manner.” Preparations for IGY had forced a consolidation of existing evidence, and an IGY-inspired Special Committee on Oceanic Research perpetuated the experience. Even as Carson wrote her paean of wonder, a flotilla of war-surplus research vessels with their sparkling instruments—their hydrophones, echo sounders, fathometers, piston corers, cameras, explosion seismometers, magnetometers, dredges, and thermal probes—was stripping the veil from the abyss. That year Lt. Don Walsh and Jacques Piccard rode the bathyscaphe Trieste to the bottom of the Marianas Trench. The imagination no longer needed to rely on analogies, poetic tropes, and appeals to “ultimate causes”: it could feast on hard data. Ideas expanded to match that empirical bounty.220

  The modernist revolution that had swept one field of inquiry after another like rolling thunder through the early decades of the twentieth century at last rumbled across geology. As IGY closed, Wilson could ponder that “No one knows with any certainty how the earth behaves, why mountains are uplifted, how continents were formed, or what causes earthquakes. We know some anatomy of the earth, but no real physiology.” Earth sciences “await” a revolution. As discoveries poured in, reformation followed. A quiet Earth became dynamic. Its sciences were reborn—renewed like its crust. Earth became the first of the planets surveyed by the remote-sensing instruments of the Third Age, and plate tectonics appeared as the founding theory of planetary science .221

  There was little opportunity, and less need, to indulge in rhetorical tropes or incantatory musings about the “unseen” and the unfathomable. The unseen abyss had been mapped. The unfathomable had been plumbed and measured. An elevated tone, if it matches its subject, works if its voice comes well before an episode of massive change or well after one. In either setting, a few select data points, stories, anecdotes, and personalities, be they people or marine worms or fishes, can be abstracted, granted an epic aura and a poetic cast, and hold up as a narrative. But during a revolution, with new discoveries rushing like a turbidity current, they cannot. Rachel Carson’s ode to Oceanus could hardly be possible after the Third Age had commenced its serious exploration: there was too much data, too many new species, too great an abundance of geologic features, a crowded, jostling, spilling-over-the-desk thesaurus of natural-history and geophysical exotica. By the 1960s there was little need to elevate rhetorically the study of the deep oceans; discovery was pouring out of the abyss and onto the continents. Thanks to the Third Age the oceans were moving to the center of Earth history. The silent abyss joined moons and distant planets as new worlds.

  Something similar happened with space. Before the advent of exploring spacecraft, the solar system seemed a tired, even clichéd subject, a relic of Newtonian physics in an age of relativity and quantum mechanics. Planetary astronomy, in particular, was a backwater, and worse, one contaminated by the fantasies of Percival Lowell and techno-romance novelists. The labors of planetary astronomers, poring over photographic plates, spoke the scholarship of classicists analyzing variants of obscure texts. Here was the laboratory turned library.

  Prior to the Third Age the study of the planets—of Earth, for that matter—seemed moribund, committed to ever-greater musings over untestable theories and refinements in its numbers, with august authorities such as Henry Norris Russell and Sir Harold Jeffreys recycling old themes and issuing ponderous pronouncements. When the newly created U.S. Air Force funded a summary series of books on planetary astronomy in the early 1950s, Gerard P. Kuiper of the University of Chicago’s Yerkes Observatory was the world’s sole professional planetary astrophysicist. When Nobel Laureate Harold Urey delivered the Silliman Lecture in 1951 on The Planets: Their Origin and Development, the same year Carson published The Sea Around Us, he devoted fifty-five pages to the “terrestrial” (inner) planets and a scant five to the “major [outer] planets and their satellites.”222

  There was some movement as astronomers occasionally directed their new instruments, from spectrometers to radio waves, toward the planets to firm up rotational periods, atmospheric chemistry, and densities; and better photographic media allowed for a trickle of discovery in planetary satellites. But the subject seemed as opaque as a gaseous giant and as dead as its. Before Mariner 2 arrived, Venus’s thick clouds had screened the planet from close scrutiny; even its rotational period was uncertain. Before Mariner 4, it was believed that Mars had no craters. The major college text of the time, Robert Baker’s Astronomy, could assert as late as 1964 that “the times of the Martian year when the dark markings change in intensity and color are such as would be expected if the changes are caused by the growth and decline of vegetation.” In a volume of 557 pages, Uranus and Neptune claime
d a page each, half of that devoted to grainy black-and-white photos. Mostly the text spoke to their discovery, not their properties. Kuiper lamented the lack of “reciprocity” between geosciences and planetary astronomy; the latter could only marvel at the “incredible richness of the data” the former possessed.223

  Then exploration blasted off and the data streamed back. IGY required three world centers to hold the rising stream. Explorer 1 found the Van Allen radiation belts. Tiros 1 began imaging the dynamics of Earth’s atmosphere, and even before the Apollo program was announced, it had photographed all the continents save Antarctica. Ranger spacecraft went to the Moon. Mariner 2 flew by Venus. Pioneer 6 amassed tape recordings, “shipped daily, big 9,600 foot, 17-inch reels”—“truckloads of tapes.” Then came the major missions, culminating in Voyager. Writing in 1981, when the Grand Tour had just begun, and focusing only on the inner planets, three prominent geoscientists remarked that their field was “immersed in a planetary information explosion.” As Voyager 2 rushed toward Uranus, JPL estimated the volume of data the mission had so far dispatched to Earth as four trillion bits, enough to “encode over 5,000 complete sets of the Encyclopedia Britannica.”224

  The exploring spacecraft had sparked a revolution. They not only amassed fresh data but also prompted astronomers to redirect their instruments (if not their minds) to the solid-bodied new worlds of space; and more than raw digits, the missions established a context for their comparison. Earth science became planetary science.

  All this—the fevered incantation of information, dazzling scenes, novel experiences, the rhythm of trek and encounter—was the cultural and psychological drive that made planetary exploration distinct from scientific observation or technological adventuring. Here was Cherry-Garrard’s Intellectual Passion leaping from Earth’s miniature ice-world of Antarctica to other planets and moons. Make it new, Ezra Pound had demanded; the robots did.

  So little had been known; so much was revealed. Looking back from 1985, Oran Nicks observed that “it is not easy to recapture the extent of our ignorance a quarter-century ago; everything we learned was new.” Everything about spacecraft, everything about interplanetary voyaging, everything about the worlds the spacecraft discovered. That was true for Mariner 2 at Venus, Mariner 4 at Mars, Pioneers 10 and 11 at Jupiter and Saturn (“everything we found out at Saturn was totally new,” Van Allen declared), and it was true for every planetary visitation by the Voyagers. Writing after the Neptune encounter, Ellis Miner declared simply that “no other experience is likely to come close to matching the excitement of anticipation and discovery that accompanied the Voyager Mission.” Those sentiments were the hallmark of a golden age.225

  To that astounding era, Voyager came as a climax. The twin spacecraft went to more places, sent back more data, did more varied things, and continued for the longest time. “No other mission,” explained Edward Stone, “explored so many different worlds” and revealed “such unexpected diversity.” After Voyager no one could see the solar system in the same way, or see Earth, or for that matter themselves, as they had before. “You only discover the solar system for the first time once,” observed Larry Soderblom. “Voyager did that.”226

  GOLDEN AGE

  A golden age.

  All those who participated in the American planetary program from Mariner 2’s flyby in 1962 to Voyager’s embarkation in 1977 agreed that this was a privileged time. Spacecraft visited virtually every planet, and revisited the closest; almost every year saw a launch; and when, after the hiatus imposed by the Challenger debacle, planetary exploration revived, it built on the legacy and hibernated ideas of those epic years. It was all “the stuff of legend and myth,” as space historian Roger Launius put it. Proponents differed only in their sense of the era’s tempo and their reckoning of its capacity to persist. They fretted because the age depended less on engineering cleverness and scientific purpose than on the whims, wealth, and mores of its sustaining society. Voyager, Bruce Murray noted, was the last mission in which “the technical challenge was dominant. Since then it’s been politics.”227

  A golden age is to history what a utopia is to geography. It is a time of the good, the just, the ideal. Good people do good things. The world works as it should. If the past can’t supply a golden age, the future might. For space advocates, that forecast future lay always just over the horizon; and after World War II it seemed it might happen in their lifetimes. Then it did happen. For NASA, the golden age of manned flight was the sixties, the age of Apollo; and for planetary exploration, the seventies, when its spacecraft visited every planet save Pluto or were on their way to do so. The ideal became the expected.

  At the time, those in the political trenches recognized what a close-run thing it was. Even Voyager had faced cancellation, or rechartering, and had downsized dramatically. The era seemed golden mostly in retrospect. The space shuttle siphoned and then hemorrhaged funding and energies away. The Reagan administration was hostile—wanted space, but in the hands of private companies or the military, and was eager to force the cold war to a conclusion, but not through proxy expeditions to other worlds. Office of Management and Budget director David Stockman sought to shut down planetary exploration altogether. Voyager—in some ways “really a product of the 1960s”—was, as Murray expressed it, “the last hurrah.” As the twins sped across the solar system, the sentiment could easily unfold that they climaxed a golden age, now lost.228

  Yet there was also a sense at the time, often a quiet euphoria, that space exploration would continue because it had to continue. The space program was more than an event: it embodied a movement of evolutionary importance on a planetary scale. It would transcend its sordid origins in the cold war. NASA could commission studies that likened the space program to the advent of the railroad, movies could be made of Childhood’s End, and otherwise sober observers might declare that outer space would revolutionize humanity more than the industrial revolution. The golden age, once arrived, would stay. That was part of the promise, and the appeal of historical utopias of all kinds across all ages. It characterizes exploration no less than other cultural endeavors.

  Yet it is the nature of history’s golden ages to be fleeting. To those living amid them, their significance becomes apparent often only at the time they are primed to implode. Before then, too much is happening to stand aside and contemplate, but it is just as the climax comes, with a softening of urgent tasks and a fading of vision, that the recent past begins to glow.

  Great outbursts of exploring enthusiasms are rare. They are possible because of distortions in the normal routine of their societies; and for that very reason they cannot be sustained. They feed off their larger nurturing culture; they can, from time to time, feed back into that culture like a self-reinforcing dynamo; but the larger dynamic comes from society, not from exploration. Geographic discovery can continue only insofar as it creates ongoing wealth. Planetary exploration expended surplus wealth; it did not create it. The great outbursts of exploring that punctuated Western history rather resemble the gravity-assisted acceleration granted by passage around a giant planet like Jupiter. Viewed from the planet, the velocity gained on approaching periapsis is also lost when the spacecraft recedes. It is only from another, more remote reference frame that the event can be seen to yield a long-term gain. So it is with the golden age of planetary exploration.229

  Many proponents refused to accept that the golden age might end, or have urged, with a progressive urgency hedging into hysteria, that it be revived and expanded. That, too, is typical, and can segue into parody. It is present in the spectacle of Hernando Cortés’s stumbling around Guatemala, Hernando de Soto’s bulling through Georgia, bold knight Francisco Coronado’s wandering through Kansas, and the Portuguese degredado (convict turned conquistador) António Fernandes’s blundering around the interior of Africa—all in search of another Mexico or Peru. After the Second Age, it resurfaces with Roy Chapman Andrews’s leading an expedition to Shiva Temple, an isolated mesa in Grand C
anyon, to search for lost worlds and with Richard Byrd leaving Little America to live by himself at Advance Base on the Ross Ice Shelf, and nearly perishing from carbon monoxide poisoning. Today it appears in proposals to sponsor another Apollo program or a national commitment to imminently colonize Mars.

  Such willful pursuits have their costs, not all dismissable as foolish vanity or misplaced idealism. Such obsessions can distort public discourse, and cabals dedicated to them can capture public policy and lead into costly misadventures. These can go beyond satire into darker parodies. If Don Quixote, a knight-errant mounted in a haze of imagined ideals, is a benign response to a lost golden age, the footloose bandeirante, an overland buccaneer opaque to anything other than slaving, raiding, and plundering, is his malign double. Yet it is hard to know when a golden age has crested, and when to adjust ambition to possibilities.

  Most enthusiasts shun even asking such questions, because to do so suggests that the recent golden age, our age, might not revive and exceed itself. But in the late 1990s, Bruce Murray did ask.

  While director at JPL, he had noted the “terrible contrast” between the technical successes of Viking and Voyager and the social failures to “reinvest” in the future. The space shuttle, in particular, he regarded as “the greatest threat to space exploration” since pre-NASA days. In April 1980 he wrote Arthur C. Clarke, several of whose books he had just finished reading, thanked him for providing “a full supply of much-needed nourishment for our imaginations and spirits in this difficult period when Man seems unable to keep up with destiny,” and invited him to JPL for Voyager 1’s encounter with Saturn. He also planned to invite Freeman Dyson and others for a session on interstellar travel. As that theme suggests, Murray, like many of his contemporaries, thought the trek would continue to the stars.230