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

by Stephen J. Pyne

  Thus, for the First Age, the grand gesture belongs to the circumnavigating voyage of the Victoria. Ferdinand Magellan was a paragon of his time, an explorer tenacious, religious, tough beyond reckoning and ambitious beyond yearning. God, gold, and glory—all filled the mold of his soul. When the Armada de Molucca, reduced from five daunting vessels to one straggler, the Victoria, completed its ambit of the world ocean, it defined the limits of what might be done (and had, in fact, consumed Magellan, dead in the Philippines). So bold was a circumnavigation that few expeditions dared to follow. But when the Second Age geared up in the 1760s, it did so with a new wave of Earth-encircling voyages, joining the two ages as one might lay a plank between ships.

  Yet however much those new circumnavigations might bedazzle the late eighteenth and early nineteenth centuries, they could not speak to the dramatic discovery or rediscovery of Earth’s continents or those lush fragments of it chipped off as islands. The floating excursions of James Cook and Louis-Antoine de Bougainville had to come ashore and penetrate inland. The man who achieved that task with cultural panache was Alexander von Humboldt. Convincing Carlos IV to let him enter New Spain, he became, as his own age appreciated, a “second Columbus,” in this case, the scientific discoverer of South America. For five years (1799-1804), accompanied by Aimé Bonpland, he explored widely, paddling up the Orinoco, traversing the Andes, climbing Mount Chimborazo, scrutinizing the archives and natural history of Mexico and Cuba. He elaborated Linnaeus’s natural-history excursion into a cross section of continents. He carried the Old World’s grand tour to the New World, where it could also gaze on monuments and relics of the past, not least those of nature. He gave empirical heft to the misty musings of Naturphilosophie. He empowered geographic science with a global reach. In the words of Ralph Waldo Emerson, he was one of “those Universal men, like Aristotle.” He personified the explorer as Romantic hero.

  While he was not the first European to boat the Orinoco or climb in the Andes, Humboldt was the first of a new kind of European, such that even when explorers of the Second Age revisited sites known to the First, they did so with original eyes and to novel ends. Symbolically, during a layover on his way back to Europe, he dined with Thomas Jefferson a month after Lewis and Clark’s Corps of Discovery departed St. Louis. For Americans the latter was the defining moment of the new age, but for Western civilization overall, that honor belonged to Humboldt, not only because he was first but because he followed the journey with decades of exhaustive research and publication, which meant his experiences could transcend mere adventure and politics and become an exemplar for others. His trek through South America defined the grand gesture of the Second Age as the cross-continental traverse.

  The task was roughly completed in the 1870s. For the Arctic and Antarctic, a journey to the pole and back became an acceptable substitute, although it never had quite the cachet, and Ernest Shackleton’s celebrated and ill-fated Endurance expedition sought to complete the circuit by traversing Antarctica. That particular achievement had to wait until IGY; by then the hype could no longer match the mood. It had a sense of cleaning up odd jobs, not of launching bold new adventures, a bit of geographic housecleaning outfitted with Caterpillar tractors instead of sled dogs. Something else would have to define the grand gesture of the Third Age.

  An era of exploration characterized by the inventory of whole planets needed something both vaster and newer than Antarctica and a deed more startling than a descent to the abysses of the world ocean. A journey to the Moon might be dramatic, but it belongs with the Norse voyaging to Greenland, or Polynesians to Easter Island, something astonishing but that leads nowhere else. The same might be said of the marvelous robotic missions to Venus and Mars, or even to Jupiter and Saturn, a brilliant expedition to a single place and theme, but not a moment that, like a parabolic mirror, concentrates all the energy around it to a focus. A grand gesture has to be something that encompasses it all, as the Victoria’s circumnavigation did, and that like its formidable captain, embodies an age in its character; that by speaking with special force to its own time, it speaks to all times; that can travel across history as the expedition does over geography.

  Voyager’s Grand Tour does this. In its design, in its scope, in its reprogrammable computers, in the ability of its mission to retain the past even as it speeds beyond it, Voyager has embodied the ideas, ambitions, hopes, paradoxes, aesthetics, flaws, and energies of its time. It has made manifest the power and peculiarities of a Third Great Age of Discovery.

  5. Launch

  Launch is a working synthesis—the possible made plausible. It reconciles motive with machinery. It welds the propellant force of rockets to ideas and instruments. It codes vision into operating plans. It is enough for prophets to find words or images to move audiences, but engineers and managers require a more tangible expression, the contact not of ink on paper or electrons on a TV screen but of metal, wires, hydrazine, lenses, and decaying plutonium. Without such labors the Grand Tour belonged in the realm of science fiction.

  Expeditions are made, they are scheduled, they occur at designated places and at specified times. They require ports of departure. They must harmonize social timing with environmental opportunities. They are time capsules of a cultural moment. The Voyagers were all this.

  TITAN IIIE/CENTAUR D-1T

  The Voyagers could not carry more instruments than what the allotted thrust and dimensions of the Titan/Centaur rocket and Centaur casing allowed. In their liftoff the Voyagers thus continued a long heritage of mixed-technology vessels, and in the staged sequencing of their flight they recapitulated an old history of vessels redesigned, vessels refitted, vessels shed, and vessels lost. And with unintended inspiration their ascent even emulated the multistage evolution of exploration itself.

  The Titan was a two-stage rocket originally developed as an ICBM, which then evolved as an all-purpose vehicle for heavier payloads such as surveillance satellites. The first stage had two engines, and the second stage, one, all of which burned liquid fuels that fired spontaneously when mixed, and rendered “ignition” a figure of speech. To the sides were bolted two solid-fuel boosters to add initial thrust. Atop rose an aptly named Centaur rocket powered by two engines that burned by kindling liquid hydrogen and oxygen and gave the hybrid a third stage. Within Centaur nested a Voyager spacecraft attached to yet another engine for a final propulsive push. Each stage fired, and then physically disengaged and dropped away, leaving the next stage to position itself and burn unimpeded without the dead weight of the husk.

  Liftoff commenced with the blast of the first stage’s engines and double boosters. As the solid rockets burned out, a suite of explosive bolts and small rockets peeled them from the core. When the first stage burned out, it, too, separated, and the second stage kicked in. When that stage exhausted its fuels, it also fell away, and the third-stage Centaur shed its shroud and its own engine caught fire. Here the Centaur demonstrated its value for such missions. It had high specific impulse, it could coast and reignite repeatedly, and it contained its own avionics for navigation and control. It was, in brief, the Centaur’s rocket that mediated between the brute blast of the Titans and the onboard solid-propulsion engine of the Voyagers.

  For each Voyager mission Centaur fired and coasted twice, once to achieve a low Earth orbit, and then again, after cruising to the ideal spot, in order to reach escape velocity and embark on its journey beyond Earth. The first episode came as Centaur jettisoned its shroud 203 seconds after liftoff and, 4 seconds later, burned for 101 seconds. Almost 43 minutes later, Centaur repositioned itself for the next burn, which lasted 339 seconds, followed by a short coasting for 89 seconds. That, at least, was the scenario for Voyager 2. The last-stage Titan faltered during Voyager 1, the result of a leak, and threatened to abandon the spacecraft short of orbit, which would have left it to finish its combustion by burning up in the atmosphere. Fortunately, the computers aboard Centaur recognized the problem and adjusted by extending their burn. Ev
en so, they barely had enough fuel to compensate; only 3.4 seconds of fuel remained when Centaur shut down. Had this sequence played out during Voyager 2, the mission would have failed, for it had a less forgiving trajectory; Centaur’s boost of burning could not have compensated. The Voyager mission thus displayed, from liftoff, that most ineffable and most essential quality of great expeditions: good fortune. If “they had swapped the Titan booster rockets,” Bruce Murray observed, “there would have been no Voyager to Neptune. Flip of the coin.” “We were lucky,” he concluded, “and that’s important.”74

  For both Voyagers, the particular trajectories required for Jupiter demanded yet another thrust. With Centaur spent, the action moved to an augmented Voyager itself. The spacecraft had a supplementary solid-fuel propulsion module under its direction. Voyager segregated from Centaur, ignited its rocket for forty-five seconds, and then shed the booster. The mission module—the spacecraft proper—was now at sea, subject to minor corrections (or “nudge” factors) to compensate for its inherent quirks and the unseen winds and currents of gravity.

  Hybrid vessels, staged launches, the practice of shedding dead weight or separating close-exploring craft from long-haul vessels—all these had ample precedents dating back to the Great Voyages themselves.

  The ships of discovery were a mixed lot, the result of centuries of evolution in the Mediterranean and a recent fusion with Baltic traditions. A critical innovation was the transfer, probably from the Indian Ocean, of the lateen sail. A triangular sheet with a long, stiff edge, the lateen demanded only simple rigging, could work amid a variety of winds, and sharpened maneuverability. It became the norm for modest-size ships and those working along coasts. But it required proportionally large crews, and could not be put about easily; nor could it run with heavy loads before the wind. The solution was to look north, and adapt the bulkier, square-sailed cog typical of the Baltic and North seas an introduction that came during the Crusades. The synthesis of these two styles occurred with exquisite geographic logic in Iberia, where the Atlantic and Mediterranean converged.

  Each tradition was further modified to circumstances over several centuries, and then suddenly joined one to the other during roughly two decades in the mid-fifteenth century. Shipbuilders borrowed and rearranged hull design, keels, spars, rudders, numbers of masts, and various sails, all tweaked into an ancestral barque from which subsequently descended miscellaneous and mongrel progeny. Some, such as the carrack, were large and designed for haulage. Some were built mostly for fighting. But the most celebrated was the caravel (caravella), a specialty of Portugal and southern Spain. Mostly Mediterranean in its genes, it morphed to accommodate a square sail and a rear rudder, and became the core ship of discovery. Small, versatile, capable of riding over waves, maneuverable around coasts and shoals, the caravel was the vessel with which Portugal mapped the coast of Africa, and along with Castile, colonized the Atlantic isles and discovered the Ocean Sea.75

  Still, the caravel was small, and long voyages required vessels of modest crews and greater capacity, so most armadas sailed with mixed fleets, of which the caravel was a part. Da Gama had one caravel, as did Cabral, and Columbus took two on his first voyage, the Niña and Pinta. (Interestingly, it was the larger Santa Maria, a nao, that foundered on a shoal off Hispaniola.) The caravels did the close work of coasting, carried messages, tested new seas, and got emissaries and explorers to previously unknown land. Few voyages lacked at least one in their company, although the most extraordinary of all, the Armada de Molucca under Ferdinand Magellan, had none. As they acquired experience, explorers turned to smaller-size carracks, which proved more capacious for crews and goods and better suited for long voyages.

  Heavy-lift rockets enjoyed a comparable evolution. They were hybrids. As with ships during the Renaissance, there were geographic traditions—in this case, with centers in Russia, Germany, and America—and some exchange between them, catalyzed by war. The Russians favored a basic model to which they added boosters. The Americans looked to a more mixed fleet, but one largely evolved from the German V-2, a process catalyzed by the capture of German rocket scientists as the war ended (the celebrated Operation Paperclip). From the V-2 evolved the Redstone, and from the Redstone, the first American intermediate-range ballistic missile (IRBM), the Jupiter; from Jupiter came the intercontinental ballistic missiles (ICBM), Atlas and Titan, separately developed for different purposes. Outfitted with a Centaur upper stage, Atlas launched seventy-two payloads over its history, and Titan, eight, of which Voyager was the last.76

  If such hybridization and tinkering has a long pedigree, so does the freelance, freebooter movement of those who had expertise. German scientists carried knowledge of the V-2 from Peenemünde to White Sands. During the era of the Great Voyages, Italian capital and merchants, mostly Genoese and Venetian, bonded with Iberian geopolitical enthusiasms to drive overseas expansion. Portuguese pilots, like Italian condottieri, were the mercenaries of discovery, serving the highest bidder. During the era of continental colonies, Germans in particular were everywhere, furnishing the technical skills in cartography and botany that locals lacked. Charles Preuss did much of the mapping for John Charles Fremont’s first, second, and fourth expeditions; Heinrich Möllhausen collected natural-history specimens and illustrated for Whipple’s reconnaissance through northern Arizona, and later Lt. Joseph Ives’s abortive voyage up the Colorado River, where F. W. von Egloffstein joined and did the critical cartography. Exploration invited the footloose and the obsessed to join whatever party would sponsor them. The Third Age is no exception.

  For exploration history add the practice of adapting vehicles developed for one purpose to another. Frijthof Nansen reworked Inuit sledges into sturdier forms for traversing rough pack ice and wrestling over pressure ridges. John Wesley Powell put modified dories into the Colorado River to descend through its succession of gorges. Captain Cook’s fabled Endeavour was a modified collier. Charles Wilkes’s flagship, the Vincennes, was a reconditioned sloop of war; Dumont d’Urville’s Astrolabe was a converted corvette; James Ross’s Terror and Erebus were refitted naval mortar ships. (They later went to the Arctic, where they sank off King William Island with Sir John Franklin.) The HMS Beagle that carried Darwin around the world began as a ten-gun brig remade into a barque and modified to slough off rougher seas. Ernest Shackleton’s Nimrod was a forty-year-old wooden sealer; Robert Scott’s Terra Nova, a barque formerly used for sealing and whaling.

  Only Nansen’s Fram was designed from scratch for polar exploration. Its heavy oak beams gave it a stiff pliability and its curved hull was designed to have the ship ride up as pack ice squeezed. Several explorers, however, devised boats that could be disassembled into more portable parts, and then reassembled as needed. Nathaniel Wyeth experimented with a design in the American West, and Samuel Baker and Henry Stanley did likewise in central Africa. The Ives Expedition to the Colorado River transported a disassembled steamboat. So it was that rockets for planetary flybys were adapted from ICBMs, and replaced MIRV warheads with multiple-instrumented exploring spacecraft.

  Those vessels, by their launch gantries, were as mongrel as the caravel-piloted armadas of the Renaissance. The heavy vehicles had to do their work first and then fall aside, their task completed in minutes and seconds upon reaching escape velocity, while Pioneers, Mariners, or Voyagers cruised through interplanetary space for months or years. In the sixteenth century the first stage could take months, tacking across winds and currents and around continents, while actual contact might exhaust itself in a few days. For this end the vessels might include a pinnace (prefabricated and carried in the hold until needed), or tow a shallop or longboat, ships that could support geographic foraging parties, or “away teams,” at new coasts, akin to surface landers dropped from orbiters. The danger was that they might be swamped during the crossing, as they often were. Except for the longest voyages, they could expect to provision themselves en route. Not least, for those expeditions that intended to finance them
selves by importing spices or bullion, heavy vessels would be needed for the return, for unlike planetary spacecraft, those exploring parties had to report in person and deliver their discoveries in tangible form; they could not transmit digital data across space. Still, early-stage supply ships could be shed, discarded like empty rocket boosters, until all that remained was the pure mission module.77

  AROUND THE CAPE

  The Voyager twins departed Earth from launchpads at a site first selected only eighteen years previous.

  In the past, exploration had not devised its own point of departure. Expeditions left from places that had evolved organically from sites of enterprise and lines of transport that, from time to time, outfitted parties of explorers as needed. John Cabot sailed from Bristol, long a scene for trade and fishing; Jacques Cartier, from La Rochelle, likewise a well-established natural port; Captain James Cook launched from Plymouth, and Captain FitzRoy’s Beagle, with Charles Darwin aboard, from Devonport, both naval depots. The Lewis and Clark expedition left St. Louis, the major entrepôt of the Mississippi River. Those countries, such as Russia, that lacked ready access to the sea lagged, or turned overland, until ports were available; for the Bering expeditions to Alaska temporary ports had to be constructed. Once in the New World, Spain promptly erected ports at Isabella, Vera Cruz, Lima, and Acapulco from which new voyages could set forth.