The Best American Science and Nature Writing 2018

by Sam Kean

  Maybe she’s right, and it will be easier than I can even imagine. At the very least, the rest of today will fall away, and what remains will be the people, the place, the quiet luck of proximity and the even quieter mysteries of our interior selves, both so chromosomally shared and so separate. Two minutes, a lifetime, the overlapping of lives. Our threaded-together fates still largely unknown.

  I want to hold my child, our heads tilted to the heavens, the very opposite image of gazing down at our devices. We will marvel at Dillard’s “old wedding band in the sky, or a morsel of bone.”

  And when the blackness peels away and August torpor clamps down again (August, I do not care for you, it’s true)—what will we carry forth? I hear my daughter, wanting to know what we’re going to do next. My husband: “Back to work.” Me, checking this off my to-do list: eclipse. None of us will be spooked right to death. “One turns at last even from glory itself with a sigh of relief,” Dillard writes. “From the depths of mystery and even from the heights of splendor, we bounce back and hurry for the latitudes of home.”

  Yet I write this wishing, impossibly, for what only fiction could bestow upon those scant two minutes: for life to irrevocably change—at the very moment when we seem vividly lost in our darkest legacies. In the absence of such wizardry, I will accept the stillness and awe experienced alongside the ones I love most. I will accept a summer day turned inside out.

  And I write this wanting to know: How did you and you and you experience the eclipse? Whose hands did you clasp at the wonder of the moon blotting out the sun, breaking the day in two?

  STEVEN JOHNSON

  Greetings, E.T. (Please Don’t Murder Us.)

  from The New York Times Magazine

  On November 16, 1974, a few hundred astronomers, government officials, and other dignitaries gathered in the tropical forests of Puerto Rico’s northwest interior, a four-hour drive from San Juan. The occasion was a rechristening of the Arecibo Observatory, at the time the largest radio telescope in the world. The mammoth structure—an immense concrete-and-aluminum saucer as wide as the Eiffel Tower is tall, planted implausibly inside a limestone sinkhole in the middle of a mountainous jungle—had been upgraded to ensure its ability to survive the volatile hurricane season and to increase its precision tenfold.

  To celebrate the reopening, the astronomers who maintained the observatory decided to take the most sensitive device yet constructed for listening to the cosmos and transform it, briefly, into a machine for talking back. After a series of speeches, the assembled crowd sat in silence at the edge of the telescope while the public-address system blasted nearly three minutes of two-tone noise through the muggy afternoon heat. To the listeners, the pattern was indecipherable, but somehow the experience of hearing those two notes oscillating in the air moved many in the crowd to tears.

  That 168 seconds of noise, now known as the Arecibo message, was the brainchild of the astronomer Frank Drake, then the director of the organization that oversaw the Arecibo facility. The broadcast marked the first time a human being had intentionally transmitted a message targeting another solar system. The engineers had translated the missive into sound, so that the assembled group would have something to experience during the transmission. But its true medium was the silent, invisible pulse of radio waves, traveling at the speed of light.

  It seemed to most of the onlookers to be a hopeful act, if a largely symbolic one: a message in a bottle tossed into the sea of deep space. But within days, the Astronomer Royal of England, Martin Ryle, released a thunderous condemnation of Drake’s stunt. By alerting the cosmos of our existence, Ryle wrote, we were risking catastrophe. Arguing that “any creatures out there [might be] malevolent or hungry,” Ryle demanded that the International Astronomical Union denounce Drake’s message and explicitly forbid any further communications. It was irresponsible, Ryle fumed, to tinker with interstellar outreach when such gestures, however noble their intentions, might lead to the destruction of all life on Earth.

  Today, more than four decades later, we still do not know if Ryle’s fears were warranted, because the Arecibo message is still eons away from its intended recipient, a cluster of roughly 300,000 stars known as M13. If you find yourself in the northern hemisphere this summer on a clear night, locate the Hercules constellation in the sky, 21 stars that form the image of a man, arms outstretched, perhaps kneeling. Imagine hurtling 250 trillion miles toward those stars. Though you would have traveled far outside our solar system, you would only be a tiny fraction of the way to M13. But if you were somehow able to turn on a ham radio receiver and tune it to 2,380 MHz, you might catch the message in flight: a long series of rhythmic pulses, 1,679 of them to be exact, with a clear, repetitive structure that would make them immediately detectable as a product of intelligent life.

  In its intended goal of communicating with life-forms outside our planet, the Arecibo message has surprisingly sparse company. Perhaps the most famous is housed aboard the Voyager 1 spacecraft—a gold-plated audiovisual disc, containing multilingual greetings and other evidence of human civilization—which slipped free of our solar system just a few years ago, traveling at a relatively sluggish 35,000 miles per hour. By contrast, at the end of the three-minute transmission of the Arecibo message, its initial pulses had already reached the orbit of Mars. The entire message took less than a day to leave the solar system.

  True, some signals emanating from human activity have traveled much farther than even Arecibo, thanks to the incidental leakage of radio and television broadcasts. This was a key plot point in Carl Sagan’s novel Contact, which imagined an alien civilization detecting the existence of humans through early television broadcasts from the Berlin Olympic Games, including clips of Hitler speaking at the opening ceremony. Those grainy signals of Jesse Owens, and later of Howdy Doody and the McCarthy hearings, have ventured farther into space than the Arecibo pulses. But in the 40 years since Drake transmitted the message, just over a dozen intentional messages have been sent to the stars, most of them stunts of one fashion or another, including one broadcast of the Beatles’ “Across the Universe” to commemorate the 40th anniversary of that song’s recording. (We can only hope the aliens, if they exist, receive that message before they find the Hitler footage.)

  In the age of radio telescopes, scientists have spent far more energy trying to look for signs that other life might exist than they have signaling the existence of our own. Drake himself is now more famous for inaugurating the modern search for extraterrestrial intelligence (SETI) nearly 60 years ago, when he used a telescope in West Virginia to scan two stars for structured radio waves. Today the nonprofit SETI Institute oversees a network of telescopes and computers listening for signs of intelligence in deep space. A new SETI-like project called Breakthrough Listen, funded by a $100 million grant from the Russian billionaire Yuri Milner, promises to radically increase our ability to detect signs of intelligent life. As a species, we are gathered around more interstellar mailboxes than ever before, waiting eagerly for a letter to arrive. But we have, until recently, shown little interest in sending our own.

  Now this taciturn phase may be coming to an end, if a growing multidisciplinary group of scientists and amateur space enthusiasts have their way. A newly formed group known as METI (Messaging Extra Terrestrial Intelligence), led by the former SETI scientist Douglas Vakoch, is planning an ongoing series of messages to begin in 2018. And Milner’s Breakthrough Listen endeavor has also promised to support a “Breakthrough Message” companion project, including an open competition to design the messages that we will transmit to the stars. But as messaging schemes proliferate, they have been met with resistance. The intellectual descendants of Martin Ryle include luminaries like Elon Musk and Stephen Hawking, and they caution that an assumption of interstellar friendship is the wrong way to approach the question of extraterrestrial life. They argue that an advanced alien civilization might well respond to our interstellar greetings with the same graciousness that Cortés showed the Az
tecs, making silence the more prudent option.

  If you believe that these broadcasts have a plausible chance of making contact with an alien intelligence, the choice to send them must rank as one of the most important decisions we will ever make as a species. Are we going to be galactic introverts, huddled behind the door and merely listening for signs of life outside? Or are we going to be extroverts, conversation-starters? And if it’s the latter, what should we say?

  Amid the decommissioned splendor of Fort Mason, on the northern edge of San Francisco, sits a bar and event space called the Interval. It’s run by the Long Now Foundation, an organization founded by Stewart Brand and Brian Eno, among others, to cultivate truly long-term thinking. The group is perhaps most famous for its plan to build a clock that will successfully keep time for 10,000 years. Long Now says the San Francisco space is designed to push the mind away from our attention-sapping present, and this is apparent from the 10,000-year clock prototypes to the menu of “extinct” cocktails.

  The Interval seemed like a fitting backdrop for my first meeting with Doug Vakoch, in part because Long Now has been advising METI on its message plans and in part because the whole concept of sending interstellar messages is the epitome of long-term decision-making. The choice to send a message into space is one that may well not generate a meaningful outcome for a thousand years, or a hundred thousand. It is hard to imagine any decision confronting humanity that has a longer time horizon.

  As Vakoch and I settled into a booth, I asked him how he found his way to his current vocation. “I liked science when I was a kid, but I couldn’t make up my mind which science,” he told me. Eventually, he found out about a burgeoning new field of study known as exobiology, or sometimes astrobiology, that examined the possible forms life could take on other planets. The field was speculative by nature: after all, its researchers had no actual specimens to study. To imagine other forms of life in the universe, exobiologists had to be versed in the astrophysics of stars and planets; the chemical reactions that could capture and store energy in these speculative organisms; the climate science that explains the weather systems on potentially life-compatible planets; the biological forms that might evolve in those different environments. With exobiology, Vakoch realized, he didn’t have to settle on one discipline: “When you think about life outside the Earth, you get to dabble in all of them.”

  As early as high school, Vakoch began thinking about how you might communicate with an organism that had evolved on another planet, the animating question of a relatively obscure subfield of exobiology known as exosemiotics. By the time Vakoch reached high school in the 1970s, radio astronomy had advanced far enough to turn exosemiotics from a glorified thought experiment into something slightly more practical. Vakoch did a science-fair project on interstellar languages, and he continued to follow the field during his college years, even as he was studying comparative religion at Carleton College in Minnesota. “The issue that really hit me early on, and that has stayed with me, is just the challenge of creating a message that would be understandable,” Vakoch says. Hedging his bets, he pursued a graduate degree in clinical psychology, thinking it might help him better understand the mind of some unknown organism across the universe. If the exosemiotics passion turned out to be a dead end professionally, he figured that he could always retreat back to a more traditional career path as a psychologist.

  During Vakoch’s graduate years, SETI was transforming itself from a NASA program sustained by government funding to an independent nonprofit organization, supported in part by the new fortunes of the tech sector. Vakoch moved to California and joined SETI in 1999. In the years that followed, Vakoch and other scientists involved in the program grew increasingly vocal in their argument for sending messages as well as listening for them. The “passive” approach was essential, they argued, but an “active” SETI—one targeting nearby star systems with high-powered radio signals—would increase the odds of contact. Concerned that embracing an active approach would imperil its funding, the SETI board resisted Vakoch’s efforts. Eventually Vakoch decided to form his own international organization, METI, with a multidisciplinary team that includes the former NASA chief historian Steven J. Dick, the French science historian Florence Raulin Cerceau, the Indian ecologist Abhik Gupta, and the Canadian anthropologist Jerome H. Barkow.

  The newfound interest in messaging has been piqued in large part by an explosion of newly discovered planets. We now know that the universe is teeming with planets occupying what exobiologists call “the Goldilocks zone”: not too hot and not too cold, with “just right” surface temperatures capable of supporting liquid water. At the start of Drake’s career in the 1950s, not a single planet outside our solar system had been observed. Today we can target a long list of potential Goldilocks-zone planets, not just distant clusters of stars. “Now we know that virtually all stars have planets,” Vakoch says, adding that, of these stars, “maybe one out of five have potentially habitable planets. So there’s a lot of real estate that could be inhabited.”

  When Frank Drake and Carl Sagan first began thinking about message construction in the 1960s, their approach was genuinely equivalent to the proverbial message in a bottle. Now, we may not know the exact addresses of planets where life is likely, but we have identified many promising ZIP codes. The recent discovery of the TRAPPIST-1 planets, three of which are potentially habitable, triggered such excitement in part because those planets were, relatively speaking, so close to home: just 40 light-years from Earth. If the Arecibo message does somehow find its way to an advanced civilization in M13, word would not come back for at least 50,000 years. But a targeted message sent to TRAPPIST-1 could generate a reply before the end of the century.

  Frank Drake is now eighty-seven and lives with his wife in a house nestled in an old-growth redwood forest, at the end of a narrow, winding road in the hills near Santa Cruz. His circular driveway wraps around the trunk of a redwood bigger than a pool table. As I left my car, I found myself thinking again of the long now: a man who sends messages with a potential life span of 50,000 years, living among trees that first took root a millennium ago.

  Drake has been retired for more than a decade, but when I asked him about the Arecibo message, his face lit up at the memory. “We had just finished a very big construction project at Arecibo, and I was director then, and so they said, ‘Can you please arrange a big ceremony?’” he recalled. “We had to have some kind of eye-catching event for this ceremony. What could we do that would be spectacular? We could send a message!”

  But how can you send a message to a life-form that may or may not exist and that you know nothing at all about, other than the fact that it evolved somewhere in the Milky Way? You need to start by explaining how the message is supposed to be read, which is known in exosemiotics as the “primer.” You don’t need a primer on Earth: you point to a cow, and you say, “Cow.” The plaques that NASA sent into space with Pioneer and Voyager had the advantage of being physical objects that could convey visual information, which at least enables you to connect words with images of the objects they refer to. In other words, you draw a cow and then put the word cow next to the drawing and slowly, with enough pointing, a language comes into view. But physical objects can’t be moved fast enough to get to a potential recipient in useful timescales. You need electromagnetic waves if you want to reach across the Milky Way.

  But how do you point to something with a radio wave? Even if you figured out a way to somehow point to a cow with electromagnetic signals, the aliens aren’t going to have cows in their world, which means the reference will most likely be lost on them. Instead, you need to think hard about the things that our hypothetical friends in the TRAPPIST-1 system will have in common with us. If their civilization is advanced enough to recognize structured data in radio waves, they must share many of our scientific and technological concepts. If they are hearing our message, that means they are capable of parsing structured disturbances in the electromagnetic spectrum, whic
h means they understand the electromagnetic spectrum in some meaningful way.

  The trick, then, is just getting the conversation started. Drake figured that he could count on intelligent aliens possessing the concept of simple numbers: 1, 3, 10, etc. And if they have numbers, then they will also very likely have the rest of what we know as basic math: addition, subtraction, multiplication, division. Furthermore, Drake reasoned, if they have multiplication and division, then they are likely to understand the concept of prime numbers—the group of numbers that are divisible only by themselves and one. (In Contact, the intercepted alien message begins with a long string of primes: 1, 2, 3, 5, 7, 11, 13, 17, 19, 23, and so on.) Many objects in space, like pulsars, send out radio signals with a certain periodicity: flashes of electromagnetic activity that switch on and off at regular rates. Primes, however, are a telltale sign of intelligent life. “Nature never uses prime numbers,” Drake says. “But mathematicians do.”

  Drake’s Arecibo message drew upon a close relative of the prime numbers to construct its message. He chose to send exactly 1,679 pulses, because 1,679 is a semiprime number: a number that can be formed only by multiplying two prime numbers together, in this case 73 and 23. Drake used that mathematical quirk to turn his pulses of electromagnetic energy into a visual system. To simplify his approach, imagine I send you a message consisting of 10 X’s and 5 O’s: XOXOXXXXOXXOXOX. You notice that the number 15 is a semiprime number, and so you organize the symbols in a 3-by-5 grid and leave the O’s as blank spaces. The result is this: