by Sam Kean
Last September, NASA’s Spitzer Space Telescope, with help from several land-based telescopes, verified two of the planets spotted by the Belgians and went on to detect five more, for a total of seven, the biggest batch of Earth-sized planets ever detected around a single star.
When my editor at California proposed that, in light of this jackpot, I revisit an old book of mine, The Starship and the Canoe, I agreed on the spot. Would I like to apply the dialectic of my book, written 40 years ago, to the seven new exoplanets? Yes, I would. Three of seven are in the “Goldilocks zone,” not too hot for life, not too cold, just right. An ideal temperature for asking again a question posed by my book: To what should we be adapting? To this blue-green sphere down here, with its single sun, good for only 5 billion more years, or to the glittery firmament above?
The Starship and the Canoe is an account of two vessels, two contrary views of our future, and two men, a father and son, hell-bent on voyaging in opposite directions. The father was, and is, Freeman Dyson, the stellar astrophysicist, particle physicist, and mathematician, a prodigy drawn since infancy to the stars, author of his first papers on planetary mechanics at the age of five, before he really got the hang of spelling. Most of his subsequent career he has spent at the Institute for Advanced Study in Princeton, with sojourns in places like Berkeley and the Max Planck Institute in Germany.
Dyson’s most unusual sabbatical came in 1958, when he moved to La Jolla to become a luminary—first magnitude—on a team of 50 scientists and engineers working on Project Orion, a scheme to explore the solar system by “nuclear-pulse propulsion.” Atomic bombs would drop from the Orion spacecraft like eggs from a duck. The bombs would detonate beneath a massive “pusher plate” at the bottom of the vessel, and enormous shock absorbers would smooth out the jolts. The team studied Coca-Cola vending machines for ideas on how to dispense their nuclear explosives. They were not keen on handing their spaceship over to any crew of astronauts. They wanted to go themselves. Their plan was to bomb themselves to Mars by 1965 and Saturn by 1970.
It was totally insane, of course, except apparently not. The Air Force and ARPA, the Advanced Research Projects Agency, funded Orion, and for a time the project held its own against the chemical rocketry of Wernher von Braun. No conceptual flaw killed Orion. What vaporized the project, finally, was the Partial Test Ban Treaty of 1963, which forbade nuclear explosions in the atmosphere.
The goal of the Orion effort was the design of a modest little ship for touring this solar system, but in one lecture, early on, Freeman Dyson strayed way outside the box. The physicist stunned his colleagues by pushing the Orion idea as far as it could go. What would it take, he asked himself, to send Chicago to Alpha Centauri, the nearest star system? What it would take, he calculated, was 30 billion pounds of deuterium loaded into 25 million thermonuclear bombs and racked in a spidery ark, a colossal “heat-sink” starship, with a base 12 miles in diameter, that would accelerate for a century and then glide on to Alpha Centauri, reaching that system, in the Orion Arm of the Milky Way, in a little more than 150 years. The cost, as Dyson figured it, was reasonable. We could perpetuate humanity in the stars for about one Gross National Product.
George Dyson, Freeman’s only son, as a preschooler was enthusiastic about trips like this, but lost interest in his teens.
George was drawn less to galaxies than to the woods. He was an explorer of New Jersey swamps, a collector of snakes and turtles. Helen Dukas, Einstein’s personal secretary, babysat him. His father’s mentor, the Nobel laureate Hans Bethe, would drop in. Professor Bethe won his Nobel for figuring out the chemistry that fuels the brightness of the stars, and then headed up the Theoretical Division of the Manhattan Project, where he helped guide that experiment to its dazzling conclusion, and then went on to stoke the small, brief sun of the H-bomb. “Bright eyes,” he remembered of George as a small boy underfoot. That was the only feature he could recall for me. Enormous theoretical firepower gravitates to the Institute for Advanced Study, but it was mostly wasted on George. He was a smart boy, but what gave him most satisfaction was working with his hands. His pastime from an early age was building model boats.
George’s parents divorced when he was six. After the breakup, he spent most of the year with his father in Princeton and often summered with his mother. The Dysons, father and son, had trouble understanding each other. George grew his hair out longer than his father liked. When he was twelve he built his first kayak in his room. Denied use of the garage, he was forced to extend construction into his closet, like an old salt building a clipper ship in a bottle. It was hell getting the kayak out again—a sore point with George for years afterward.
When George was fourteen, a package arrived for him from California and was intercepted at the post office. He had spent the summer with his mother, the mathematician Verena Huber-Dyson, who was teaching at Berkeley, and he had discovered the Haight-Ashbury. The package contained marijuana. George was arrested in class and led away in handcuffs. “That really raised my status around there,” he says, but admits that it also dropped his spirits. His father thought he should stay in jail a while, so as to learn his lesson, and this led to what would become a six-year estrangement.
At sixteen, George enrolled at UC San Diego. He didn’t like it, so after a few weeks he transferred to the Berkeley campus, where he didn’t like it either. Skipping class, he found himself strolling the Berkeley Marina past a sailboat with a “For Sale” sign. He bought it, spending almost all his allotment for school expenses. He moved into his boat, cooked in the galley on a Primus stove, and slept on one of his four narrow berths. When he studied, which was infrequently, he liked to sail to Angel Island and anchor in Richardson Bay while he read.
Two summers earlier in the Sierra Nevada, he had worked as a pot-washer for my sister Barbara, who was cook on a Sierra Club trip. (“Twenty-five dollars a week,” he recalled recently. “My first big break in life.”) On arriving at Cal, he looked Barbara up, and now and then, when he needed company or his ship’s larder ran low, he visited our Berkeley house. He and my little brother, John, who are the same age, became very close, de facto brothers. My brother Bob, an anti-industrialist, was president of an imaginary company he had founded, the Strange Development Corporation, all its products conceptual. Seeing promise in George, he appointed him vice president. My father, then the executive director of the Sierra Club—an actual organization—overheard George’s mission statement and would quote it in speeches for the rest of his life: “To find freedom, without taking it from someone else.” My mother, then editor for the Department of Anthropology, came across George once in the kitchen reading the ingredients on a bag of dog food. He had been policing the shelves for additives. “This is the only thing in the house that’s fit to eat,” he muttered.
George lasted just one term at Berkeley. Selling his boat, he moved up to British Columbia and took up residence in a Douglas fir outside Vancouver, building a tree house 95 feet above the planetary surface. The house incorporated 14 branches as structural members and was lashed to the tree, not nailed, for the treetop swayed in the wind and the attachment had to be flexible. The single small room, shingled inside and out with red-cedar shakes he split from a drift log, was narrower than George is tall. His bed, Procrustean, had octagonal windows at head and foot. There was a small wood-burning stove. Working on boats in the labyrinthine straits and sounds of the Northwest coast, George went barefoot often and tanned so dark that he was sometimes taken for an Indian. He dedicated himself to resurrecting one of the finest of indigenous North American skin boats, the Aleut kayak—the baidarka, the Russian sea-otter hunters called it. His first big effort was a 30-foot baidarka with cockpits for three. As fieldwork for my book on the Dysons, I paddled that vessel with George from Glacier Bay in Alaska down to Canada. Then in 1975, he took the idea “kayak” as far as it could go. He built an analogue to his father’s starship, a 48-foot canoe with six holes for paddlers, Mount Fairweather, the biggest kayak in
the world.
TRAPPIST-1 is an auspicious acronym, given my assignment here. Planetesimals, represented by the second P, happen to be Freeman Dyson’s favorite heavenly bodies, the most promising extraterrestrial spots for human habitation, in his view. And the whole of the acronym has a nice echo of George. Trappist monks live in isolation, eschew idle talk, eat a vegetarian diet, and make their own bread and beer. These are the Rule of Saint Benedict. A nearly identical code, homegrown, guided the laconic young man with whom I tried to start up conversation on our kayak trips. In the tight little monastic cell of his tree house, rocked to sleep by the flex of his treetop in the wind, George was Trappist in all but the vows.
There was something for me, too, out there in Aquarius, a kind of delayed synchronicity. The telltale light of 2MASS J23062928-0502285, the dwarf star—the very photons which, by blinking as the seven planets transited the dwarf’s face, revealed the existence of the group—was emitted 40 years ago, even as I, half a lifetime and 232,000,000,000,000 miles away, tapped out, on a quaint machine called a typewriter, the final sentences of The Starship and the Canoe.
The NASA webpages on the new solar system open with an artist’s conception of the surface of the sixth planet, TRAPPIST-1f. The painting is beautifully done. It belongs in the genre of cover art for science-fiction novels, except that there is no spacecraft, or alien, or scantily dressed space maiden in the picture. A channel of open water—or open liquid of some other molecule—leads out between icebergs across a wine-dark sea to the horizon, where the dwarf sun sets. The sky is spitting snow or sleet. (If future colonists are lucky, this will be H2O snow, not frozen flakes of CO2, such as fall on the southern hemisphere of Mars.) The scene looks very Antarctic, except that the ultra-cool dwarf, in its nearness, looms four times larger than our sun and burns much paler and cooler.
Next comes a 360-degree view from an imaginary spot on the surface of TRAPPIST-1d. You scroll horizontally past black, striated boulders—basalt, from the look of them—embedded in flats and berms of pale sand. Having come full circle on the planetary surface, you can scroll vertically down into the sand at your feet or up into the hazy red sky.
This is all NASA moonshine. If we know anything with absolute certainty, it is that none of these TRAPPIST worlds will look anything like the depictions. Every planet and moon in our own system, once we have come to know it intimately, has proven to be a complete surprise, entirely its own world, unlike any other. Why should it be any different out in Aquarius?
“The discovery is a huge piece of luck,” Freeman told me of TRAPPIST-1.
The physicist, now ninety-three, continues to follow closely all the news from the stars, as he has done for the past ninety years.
“Luck that there happens to be a very small star so close to us with the planets lined up precisely in the plane where we can see them transiting. But it is not only luck. The people who planned the observations knew what they were looking for. The smaller the star, the bigger the fraction of light that each planet will obstruct, and the more precisely the planets are seen and measured. I was excited by the discovery as a triumph of intelligent observation.”
The seven planets make a cozy system, orbiting at such close quarters that the surface details of some would be visible to the naked eye from others. (Cozy but dizzying, as a year in this incestuous whirl of sister planets lasts between just 1 and 20 Earth days.) One might guess that Freeman would be charmed by this system as a place to colonize. I doubted it.
“First I have to clear away a few popular misconceptions about space as a habitat,” he told a London audience in a 1972 lecture. “It is generally considered that the planets are important. Except for Earth, they are not. Mars is waterless, and the others are for various reasons inhospitable to man.”
Much more promising, Dyson said, were the comets, small worlds a few miles in diameter, rich in water and other chemicals essential to life. Thousands of millions of comets, loosely attached to the sun, await us out there, by his estimate, with a combined surface area a thousand or ten thousand times greater than Earth’s. Closer in, in the big gap between Mars and Jupiter, is the belt of the asteroids, the rubble of collisions between two or three planets no longer there, except as fragments. There is water in the asteroids. They should make prime real estate, in Freeman’s opinion. Ceres is 593 miles in diameter. Pallas is 319 miles wide. Eros, in outline roughly the same shape and twice the size of Manhattan, tumbles through space like a dead cigar or a severed whatever. Icarus, a boulder a mile in diameter, flies awfully close to the sun, but otherwise might make a congenial outpost for some physicist’s reclusive son or some other type of hermit.
“I am not impressed by the hype about the Goldilocks zone,” Freeman said, when I asked. “The purpose of astronomy is to look at everything in the universe and find all kinds of unexpected mysteries. Of course an Earthlike planet is especially interesting because the Earth has such a rich history and geography. But there is no strong reason to expect life to be confined to any Goldilocks zone. Life as we know it is wonderfully adaptable, and Nature’s imagination is richer than ours.”
What does impress Freeman is the volume of information that space telescopes like the Spitzer and the Kepler are sending back to us. Both these infrared telescopes are now busy monitoring thousands of stars in the constellations Cygnus and Lyra. It is the Spitzer telescope that verified the last four TRAPPIST planets.
“This find is only one item in a huge treasure of discoveries made by missions like Kepler,” Freeman said. “Kepler observed with high precision the variations of light from individual stars. The public only hears about variation caused by transiting planets. There is at least as much variation caused by internal processes in the stars. For most professional astronomers, stars are more interesting than planets. There will be many more missions like Kepler in the future. To me, the great news is that we are at the beginning of a new era in the exploring of the universe, with a far more detailed understanding of both stars and planets. The seven-planet system is like the panda in the San Diego Zoo, rightly admired as beautiful and as a public attraction. But the zoo as a whole is more important than the panda.”
In summer of 1975, in my VW camper, I drove Freeman and his daughter Emily from the Nanaimo Ferry 150 miles northward through the forest of Vancouver Island to Kelsey Bay, where we took another ferry to Beaver Cove for a reunion with George. Freeman did not mind my coming along. He and his son had been five years apart, and he thought that having a third party on hand, as intermediary, made sense.
“The big moment,” he said, as the ferry reversed engines and the water churned against the pilings of the slip. I spotted George walking down toward the waterfront: knit cap, stiff oilskin jacket, familiar gait. I pointed him out to his family, who had yet to know him as a grown man. George, for his part, didn’t recognize us until I had driven off the ferry and pulled up alongside. Beaming, he and his father shook hands vigorously and kept at it for a long time.
Over the next days, we visited George’s acquaintances in the maze of glaciated islands at the foot of Queen Charlotte Sound. First we crossed to Swanson Island, which for the moment had just one inhabitant, George’s friend Will Malloff. The other half of the population, Will’s wife, Georganna, a sculptress, was temporarily off island. Malloff is inventor, among other things, of the Alaska mill, which is in widespread use across North America by people returning to the land. He had come to Swanson Island four years before with $50 and a chainsaw. Since then he had built, or salvaged from elsewhere, a whole settlement: house, greenhouse, sheds, chicken coop, duck pen, pheasant aviary, and separate workshops for himself and Georganna, whose sculptures stood everywhere in the clearing and deeper in the forest.
Malloff and the other inhabitants of this temperate rainforest fascinated Freeman. They demonstrated, he believed, the hardiness and resourcefulness that will be required of pioneers in the comets or stars. To the amusement of his son and everyone else, he tried to recruit George�
��s people as space colonists. His special target was Malloff. One day we watched from shore as Malloff waded out in his gum boots, bent over his Mercury outboard, and commenced repairing its blown head gasket. Reaching for the Vise-Grip pliers in his back pocket, he had a thought.
“I won’t let him send me into space unless I can take my Vise-Grips!” he swore, gesturing with the pliers.
“I can’t send you,” said Freeman. “You have to want to go yourself.”
Watching George and Freeman together on the island, I was struck anew by their close resemblance. George is a taller version of Freeman. Both men are lean, with large noses previously broken. Both laugh a characteristic Dyson laugh in which the shoulders shake but no sound comes out. Both have piercing eyes they hold wide open. (George’s mother noticed, early on, this thing with the eyes. In her diary entry for February 10, 1954, when her son was not quite one year old, Verena Huber-Dyson wrote, “George sometimes seems to have Freeman’s unicorn look in his eyes. That glimpse of Thurber’s unicorn reaching out for the lily simply haunts me.”)
Where I had thought my book on the Dysons would be a simple story of opposites, it was proving much more complicated and interesting, a story also of convergences. Both Dysons believed in small, creative societies (which Freeman had found in his Orion team, and George in places like Swanson Island). Both wanted to get far away. Both craved a fresh start.
If in George’s teen years, the trajectories of the two Dysons were headed straightaway toward diametrically opposed vanishing points, then by Swanson Island their arcs were beginning to come back around. The curvature of space-time, or whatever is bending this process, would appear to be sharper than Einstein calculated; it has now brought the Dyson worldviews closer than I would ever have imagined back then. George today still has a kayak workshop, but it is mostly idle. He is now a historian of science and the author of books on the evolution of technology: Darwin Among the Machines, and Turing’s Cathedral, and Project Orion. The barefoot days are over. At his TED Talks he wears shoes.
