The Smallest Lights in the Universe

by Sara Seager

  If Jack could name one gas so easily, there must have been more; either way, one was enough to explode our theory. William, Janusz, and I were dispirited but not defeated, and we went back to work. We soon came up with a staggering result. Given Earth’s surface temperature and atmospheric pressure, more than fourteen thousand molecules can exist as gases, and a quarter of them are produced by life on Earth. Who knew which of them might be produced by life on another world? That confirmed how careful we needed to be in our search. Finding an alien atmosphere rich in oxygen would be a groundbreaking discovery. But it’s far from the only possible sign of life. Oxygen is one of thousands.

  Our rapidly expanding database was criticized by many of the other scientists working on biosignature gases. They were adamant that only oxygen, methane, ozone, and a handful of other gases would ever be produced in large enough quantities for us to detect. I didn’t care. I had worked hard to permit myself a more expansive definition of life. I knew that our work would serve as the foundation for more research, the launchpad for who knew how many other discoveries, for countless dreams.

  Janusz had already unearthed something amazing on his own. He’d looked at those gases and solids that aren’t the products of biology and found specific, unmistakable patterns in them. There are fragments of molecules—we named them “motifs”—that life largely refuses to make. We had the feeling that motifs, those biochemical voids, were as filled with possibility as an unexplored ocean. Nobody knew what we might find in them.

  For instance, if we look at the hundreds of thousands of different molecules that we know life does create, about 25 percent of them contain nitrogen. About 3 percent contain sulfur. Those are two fairly abundant elements in our world. But it’s extremely rare to find molecules with nitrogen-sulfur bonds. That surprised us, because nitrogen-sulfur bonds are common in industry and pharmaceuticals; we force that union all the time in rubber manufacturing and for a variety of dyes and glues. But life? Life almost always avoids forging those bonds, and when it does, they’re often toxic.

  Instead, life often bonds sulfur with hydrogen. Proteins containing that compound are ubiquitous; they likely exist in every cell of every organism on Earth. Together, the three of us theorized that nitrogen-sulfur compounds and sulfur-hydrogen compounds can’t easily exist in each other’s presence in nature. Life on Earth has chosen hydrogen as one of sulfur’s most common partners, and nitrogen will rarely be invited to join. They are close to mutually exclusive.

  Does that mean that if we find an exoplanet with nitrogen-sulfur compounds in its atmosphere, it must not harbor life? Not necessarily. Some of my peers might argue that ignoring the lessons of life on Earth will make the parameters of our search impossibly broad. I disagree. If my research into biosignature gases has taught me anything—and it has taught me many things—it’s that life will find its own way, and it isn’t always the same way twice. We need to think more radically, not less.

  So let’s imagine.

  Imagine for a moment that we somehow visited that strange planet bathed in nitrogen-sulfur compounds. We would land our rocket on its surface. Whatever life might be there, especially if it’s intelligent life, would presumably gather to meet us. We would crack open our hatch, step out onto that alien surface, and reach out our trembling hands. And the sulfur-hydrogen compounds in our bodies would leach through their skin and contaminate the nitrogen-sulfur compounds in their bodies, and the reverse would happen to us. We’d poison them, and they would poison us, and everybody and everything would begin a slow, deadly march toward an apocalypse of chemistry.

  The same would hold true if those aliens came here. If they ever open that door, life as we know it wouldn’t just change. It would disappear. Earth would begin again. And something new would take our place. Life would find another way.

  * * *

  ●

  I was on the train home from MIT, doing my version of staring into space, thumbing through my cluttered in-box, when I saw an email from the MacArthur Foundation. Seeing that name gave my heart a little flutter. The MacArthur Foundation gives out the famous so-called “genius” grants: $625,000 over five years, no strings attached, given to people for doing inspired and inspiring work in every conceivable field.

  The email said they had tried to call me earlier that day, but my protective assistant had refused to put them through. I supposed that they hadn’t offered the MacArthur name, and he had assumed it was an especially trumped-up crank, vast networks of which now reached my office weekly. It was as though every new planet brought with it another conspiracy theory, and I had become famous enough to become one of their many targets. I couldn’t be mad at my assistant. He was doing what he thought was right, and I was grateful that he was so protective of me. Still: Not being told about a call from the MacArthur Foundation! I can’t imagine that had happened very often.

  I wrote back apologetically and asked them to try calling me again the next day. That left me with a long night of wondering to endure. What could they want? A year or two before, they’d called me to check the references of an acquaintance they were planning to honor. Maybe they wanted me to help vet someone again? That was probably it. They needed a source, not a subject. But as I watched the trees streak past the train’s windows as though they had lifted out of the ground and broken into a run, I couldn’t resist the thought: Maybe it’s my turn.

  They next day they called again. This time I picked up. They asked if I was sitting down, which I was, though I had already started floating out of my chair.

  It was my turn.

  Sometimes in life, something momentous happens to you, but you realize the enormity of its impact only in retrospect. It takes time for you to understand its significance, how some seemingly innocuous choice or unforeseen event made all the difference for you or for someone you love. The phone call from the MacArthur Foundation wasn’t like that. That phone call was one of those rare times when I knew something life-changing was happening in the moment that it was happening. I could hear people in the hall outside my office who had no idea what was taking place on my side of the door, but I knew. In that moment, I almost stepped outside myself, the object of an experiment: Watch what happens when someone’s world takes a turn.

  “Now, Dr. Seager, this is a secret,” the people on the phone told me. I had to keep the news of my win to myself until the public announcement of the awards, scheduled for later in September, a little more than three weeks away.

  “You can tell one person,” they said.

  They meant it as a consolation, as a balm: We know this is a secret that’s too big to keep, so here is our gift to you. Except that it didn’t feel like a gift. I could tell one person, because I was supposed to have found my one. I had. But then I had lost him. I’m not sure that I’ve ever felt Mike’s absence more deeply than I did then, in a moment that had been made of the most delicate, perfect glass. I had received some of the best news of my life, and the second I hung up the phone—“Thank you, thank you so much!”—I was wracked by sobs. I remembered again the promise I had made to Mike when everything but our needs and wants seemed in short supply: We’ll have time someday. We’ll have money someday. We’ll have time and money someday.

  Now I had money, at least. But you can’t keep a promise to a husband who isn’t here anymore. You either keep it when he’s alive, or you don’t.

  I knew instinctively, the way you know that a cold is going to be a bad one, that I was about to suffer one of the deeper strains of sadness. It wouldn’t just come and go on its own; I would have to fight it if I wanted it to leave. I had asked if I could tell two people, and the MacArthur Foundation was kind enough to say yes. I was thinking of Max and Alex, but then I changed my mind. Why would they need to know in advance that their mother had won an award they knew nothing about? Instead, I told Melissa. She roared like a lion.

  And I told Charles. He was surpris
ed that I’d share such a big secret with him when we were still keeping so many.

  The day before the announcement, I also told Marc Kastner, the MIT dean who had been so supportive of me when I was faltering. The money that he had found had paid for more hours for my small army of help. Each hour they worked was another hour for me to do my work. I went to his office and thanked him for every one of those hours. He surprised me by giving me a great big hug. I’m not the most huggable person, but he was ecstatic for me and I think for MIT, too. Only seven years before, there was such skepticism about whether I should have been hired. More recently, I’d been in his office talking about quitting. I was that overwhelmed little girl standing by a lake in the nighttime. Now I was about to be called a genius for everything I had learned since.

  * * *

  ●

  I woke up the morning of the MacArthur announcement with a strange feeling in my stomach. Things felt almost anticlimactic. The reality hadn’t sunk in entirely, but I’d had weeks to process what the award meant for me. I had decided not to spend the money on anything dramatic, other than a big gift for the boys and a few more trips. Being a working single parent is expensive, and even with Marc’s help, I had plundered most of my savings, forging ahead without any real plan or hope for stability. Now I’d been thrown a financial life ring. I would put most of the grant toward childcare and groceries and help around the house. I still did some chores—I even liked doing laundry, with its stark before and after—but I had learned by then that there were vast swaths of human existence that I would never master, and that was okay. There were other things at which I was one of the best. It would be a relief that I could finally talk about the MacArthur—that secret proved really hard to keep—but mostly that day was about the outside reaction to the honor, not my own. I already knew how I felt.

  The moment of the announcement was like hearing a knock at your door and opening it to find a parade. MIT sent out press releases; colleagues and students stopped by my office to congratulate me; Max and Alex were with Diana in a pizza joint and saw me on TV; my phone chimed constantly and my in-box filled up until it overflowed. The attention was flattering, of course, and everyone was very kind. I still felt a little hollow.

  In the chaos, I gave a phone interview with The Globe and Mail, a national newspaper in Canada. I wasn’t in the right space to sound as magnanimous as I should have. The reporter asked me why I had left Canada to come to the United States, and I was surprised enough by her question to answer frankly: “Because America is better at fostering greatness.” I tried to catch myself, realizing how that might sound back home: “But don’t forget to put in that I still love Canada,” I said. She included the entire quote, which made me sound less than genuine. I really do love Canada; it had just offered me different gifts than America had.

  We also talked about my widowhood, and I told her how the MacArthur people had given me permission to tell two people. I’d told my two best friends, I said. I hoped that Charles would read the story and connect the dots. I was stuck in the middle of one of the hardest lessons of widowhood: It’s the happiest moments when you feel the most alone. I was desperate for that day to have some love in it.

  Then there they were, just waiting for me to hang up the phone—the Widows of Concord, cheering and clapping and smothering me with hugs. My legs almost gave out. I’m still not sure how Melissa managed to corral everybody into my office, with just enough room for their wide smiles and open arms, a picnic lunch and bottles of chilled champagne. We sat down at my long wooden office table and dived into a feast. I basked in their warmth. I was sitting next to six suns.

  The last time so many of the Widows had been in my office, it was back when I was thinking of quitting. Now they were popping champagne corks into my ceiling, some of the only true friends I had made in my entire life, telling me that they were proud of me, they were happy for me: “What are you going to do with all that money? Sara!”

  Winning the MacArthur was a blessing. It would do for me exactly what it was designed to do. It would encourage me to keep going in an almost literal sense: It would put courage into me. It would bring me the privilege of focus. But the Widows were the fellowship that mattered most to me. Underneath our celebratory surface, we all knew the real reason they were there. Nobody had to say it. I looked around that room and felt the day’s first hint of a genuine smile on my face. Not because I wasn’t sad anymore, but because I would never again be alone in my sadness. I held up my empty glass and waited for it to be filled. I knew that it would be. The Widows had always known what I needed before I did.

  * * *

  ●

  At the end of the month, NASA announced its latest exoplanet finding, this one by Brice the Swiss and other members of my research team. I had coauthored their paper. For three years, the Spitzer and Kepler telescopes had both been trained on the same mysterious world: Kepler-7b. Back in 2010, the planet had been one of Kepler’s earliest finds, a hot giant one and a half times larger than Jupiter, orbiting so close to its star, Kepler-7, that its “year” is five days long. By way of orientation, Kepler-7 is part of the constellation Lyra; its better-known neighbor, Vega, is one of the brightest stars in the Northern Hemisphere.

  Kepler-7b had been confounding from the beginning. It was brighter in its western half than its eastern one, but it was hard to know why. Perhaps Kepler-7b somehow had its own source of heat and light. Or maybe there was some other explanation for the imbalance. That’s when Spitzer took over from Kepler. Fixing its infrared gaze, it helped determine that Kepler-7b was scorching hot, reaching temperatures perhaps as high as 1,800 degrees Fahrenheit—but it wasn’t as hot as it should be, given its proximity to its star. It was finally inferred that the planet’s western half was enveloped in a protective layer of clouds. They were reflecting the heat from Kepler-7, the way our atmosphere offers us relief from the sun.

  An artist then painted our first portrait of Kepler-7b: dark and banded in its east, and wrapped in green clouds in its west. Kepler-7b was too hot to sustain life, but we had seen a glimpse of its face. Only a few centuries ago, we were drawing dragons on our maps to mark the ends of our oceans. Now we had divined something about the weather on a planet that orbits a star in a constellation the ancient Greeks had thought looked like a harp.

  There are times when our progress can seem impossible, especially when we remember we’re the same species that murders each other for oil and fills our oceans with plastic. But it’s important that we take the time to appreciate how far we have come. It makes it easier to believe that we might go farther still.

  When the news about Kepler-7b was revealed I was on a flight to Hawaii, soaring in more ways than one.

  A tall man named Charles was in the seat beside me.

  * * *

  ●

  Charles and I were in different versions of the same unwinnable fight. He had a wife, but they were not happy and were in the middle of a long and painful separation. It had taken a miserable amount of time for their marriage to unwind; he had been sleeping on the couch for five years or so. She had told him what a failure he was for so long that he looked in the mirror and mistook beauty for hopelessness. He woke up and went to the same job he’d always had, one of two sons in a business of father and sons, stuck in the same traffic, trapped at the same intersections. His only escapes were those days he spent in the sun in Tiny and those nights when he looked up at his giants, the stars. Now he was about to turn fifty. “What am I supposed to do?” Charles said.

  I was flush with my MacArthur grant money and the hubris that the mantle of genius can bring. Charles’s fiftieth birthday was the first day of October. I invited him to come to Hawaii with me. Max and Alex could stay home with Rachel, their fun and obliging aunt from Alberta, and I could do some work and give a talk to justify the time away a little. Charles and I could stay on Mauna Kea, and I could call in a favor from a fri
end for a special tour of its telescopes. Whether Charles knew it or not, he had given me so much. He had shown me that I deserved happiness, and that it was possible for me to be happy again. It was my turn to give him something in return.

  Charles said yes, and soon we were sitting beside each other on a plane over the Pacific. We had taken to sending the same text every time one of us had boarded a plane on our own: If my plane crashes and I don’t make it, I always wanted to tell you…We would never finish the thought, leaving something important unspoken. Then, after we landed, we would text again: My plane didn’t crash, so I guess I don’t have to tell you. It had always made me smile. This was the first flight in months for which I hadn’t needed to send the text.

  We were still leaving something important unspoken. We were going as friends: separate rooms. I told myself that—friends, we’re only friends—and Charles never offered anything that seemed like a correction. I was still trembling with excitement. We could talk to each other without instruments, if only for a little while.

  We stayed in an observatory dormitory that’s 9,000 feet above sea level. We weren’t in the Hawaii of postcards. It was cold and hard to breathe. I’m always a little dreamier at high altitudes, and on that trip I surrendered completely to the gauzy spell of mountaintops. Charles and I visited my astronomer friend and toured the telescopes, assemblies of some of the most reflective glass on Earth.