The Smallest Lights in the Universe

by Sara Seager

  Luckily, Max was a good sleeper, and Mike had already started taking care of more than his share of the rest of our world. I worked mostly when Max was napping, when I could get some blocks of quiet. Once I stayed up all night to meet one of Cash’s deadlines, working on atmospheric simulations, stopping only periodically to breastfeed my stirring baby boy. I’d rock in a chair with him, nurse him back to sleep, and then return to my code, to my algorithms, to my second, third, and fourth Earths. I was exhausted, but I was also content. I was helping to make two great things.

  We made a successful proposal to study the possibilities for launching a giant pinhole camera into orbit. Jon Arenberg from Northrop Grumman reached out to Cash to see whether his company might help develop the screen; they were experts in building what we call “large deployables” in space. Their meeting came to a surprising conclusion. Jon convinced Cash to scrap his pinhole camera and design a smaller shield, returning to something much closer to the original vision but with a precisely calculated shape. Cash understood, as most mathematicians did, that the ideal geometry for a shield would be the product of an equation, a simple, elegant, provable sum. He also feared it would be nearly impossible to solve.

  He spent the next several months working on the age-old problem of seeing the firefly next to the searchlight. Cash is the classic astronomer, hooked on space from an early age. He was eight when his principal obsession switched from dinosaurs to the stars. He has never looked back, only up. Today he has silver hair and a silver beard; he keeps pens in his shirt pockets. His résumé is impressive: He helped design parts of Hubble and other major missions. The star shield was his next grand adventure. He first tried dozens and then a hundred different designs, mostly flower-shaped, writing code and running elaborate, fruitless calculations. He never managed to block enough of the star. There was always interference. There were always rings of light radiating beyond the edges of his shield.

  Cash had succumbed to the scientist’s version of tunnel vision. He was stuck on a particular type of flower, something like a lily. Each of his designs had petals that radiated from the same small central focal point. In 2005, nearly two years after he had started work, he asked himself a new question: Why not a sunflower?

  He started fresh, with a design that included a large disk in the middle, with the petals attached to it rather than to each other. He experimented with designs using twelve or sixteen petals, ballooning halfway along their lengths before tapering to fine points. The shapes of those petals changed in subtle ways, but those small changes mattered less than his choice of flower, which seemed to work. His calculations proved that a sunflower, thoughtfully shaped, would block out exactly enough starlight to expose any Earth-like shimmer next to it. He proposed a final design that would be about fifty meters across, made of light, durable materials, suitable for a life in space. It was, by most reckonings, the most practical shield design ever devised. Cash made a model of it, delicate and precise. When he held it, his eyes betrayed a flash of almost paternal pride.

  Cash invented a new word to describe his version of the shield: “Starshade.” He led a serious proposal to NASA in 2006, suggesting that the Starshade be built and launched alongside the James Webb Space Telescope, then scheduled to rocket into the black in 2018. They would orbit fifty thousand kilometers apart, kept in constant contact via radio waves. Cash thought we might see another Earth with them. We might divine distant seas. Clouds. Water. Life.

  NASA listened. Then they rejected his proposal. Cash returned with proposal after proposal, but each was rejected. He couldn’t begin to understand why. First the Terrestrial Planet Finder was canceled, now the Starshade was cold-shouldered. He decided that NASA was too risk averse. They knew they could build space telescopes; they didn’t know if they could successfully build the Starshade. Around the country, small pockets of researchers at Northrop Grumman, Princeton, and the Jet Propulsion Laboratory in California fought hard to invest in the technology, to keep the flame lit over the years to come. But the Starshade never came anything close to being built. NASA never did say yes.

  Instead, years later, in January 2013—boys back to school, snow in the trees—they put out their call for applicants for two new STDTs, one seeking to blot out the stars from within the telescope, the other from without. I applied to help build the shield, burned a little hot while doing so, and waited for fate-turning word from NASA.

  * * *

  ●

  The news arrived that April in an email from Doug Hudgins, a physical chemist at NASA. Doug is the sort of person who builds his own telescopes. The last sentence of his official bio reads: “His telescopes include a 24-inch f/5 Newtonian (home built) and a Meade seven-inch f/15 Maksutov Cassegrain.” He is a fellow obsessive, a true believer in the search for other life in the universe. I was in my office at MIT when word from him landed in my in-box. It started with Dear Sara. That seemed promising. I kept reading, and my mouth began to drop open.

  I am sending this message to let you know that we have completed our review of the applications submitted in response to our call for membership on the two Exoplanet Science and Technology Definition Teams (STDTs) that we are establishing. In that regard, I am pleased to inform you that not only would we like you to serve as a member of the Starshade STDT (Exo-S), but we would like to invite you to Chair that team.

  A few lines later, Doug concluded with an almost disarming humility:

  I would appreciate it if you could confirm your willingness to serve on the Exo-S STDT, and also let me know if you are willing to accept our invitation to Chair the Exo-S team.

  I pushed back in my seat and breathed. Willing to accept our invitation to Chair. Seven words had rarely meant so much to me. Leading an STDT is a massive honor. The timing of this particular STDT meant that it was also a big responsibility: The Starshade might finally get built because of our efforts. Or it might never get built—because of our failures. We might be the fatal last flicker of Lyman Spitzer’s dream.

  I saw a lot of qualities in myself, good and bad, but I had never seen myself as a leader of something as monumental as the Starshade, especially not at such a pivotal moment. I knew I was smart enough. I had put in the work, and I had all the necessary late-night visions. But in my mind a leader was confident, poised, organized, in control. I was still uncertain, prone to meltdowns, flustered, and barely keeping things together. I never did have a capacity for self-delusion. I was brutally honest, with myself most of all.

  I had been recently reminded just how close to the edge I now lived. I had taken the boys on a working vacation to the Pacific Northwest. Flying home through Toronto, we had to clear American customs at the airport. The immigration agent was unusually chatty, asking Max and Alex about their adventures. Then he turned to me: “Does their father know where they’ve been?”

  “He died,” I said, doing my best to maintain my composure. In an instant we were under dark skies. “Would you like to see the death certificate?” I asked. That’s one of the secret burdens of widows: They have to carry proof of their suffering for the authorities. Passport, plane tickets, death certificate. The agent shook his head, obviously rattled.

  I couldn’t fool myself into thinking that those memories were buried. They were always right there, waiting, and now I worried that they might surface in some terrible way, causing me to lose the focus that the Starshade would demand. It was impossible for me to know what might open the gates or how wide they might be opened. I’d written in my Huffington Post op-ed that women in science—as in so many fields—often have to work harder than their male counterparts, especially to earn and keep positions of leadership; they bear higher burdens of proof. They are suspected as too emotional for such cool, clinical work. Too fragile. Too shrill. Never mind that men in my field were and are capable of outbursts and tirades. Of course they are: They are passionate human beings, invested in something they love. But I
wouldn’t receive so understanding a judgment. I was always careful not to show my emotions at work; working on the Starshade, I would have to be even more careful.

  I was still sitting at my desk when I started building the counterargument to my concerns. I made the case for me. I had, I reminded myself, expected an invite to this group, albeit as a rank-and-file member. I remembered my formal education, all those years in classrooms and labs, researching, coding, building. I had made major advances in the field of exoplanets. But I had also gone on a different journey, covering a different kind of distance. I had lost my husband, and I had survived. I had built a new life for myself. I had made a new kind of family. I had found new friends and new places. Not many people had as much experience as I did with new. I could help make a new piece of hardware.

  I said yes.

  They passed along the names of the rest of the team. My phone rang almost immediately with a call from one of them: Webster Cash. He said that there must have been some mistake. Obviously he should be the chair. He was older, more experienced. He had been working on the Starshade for years. He knew more about it than I did. He knew the right shape. He had even invented the word for it: Starshade.

  It was a gut-check moment. I had always liked Cash; I still do. He’s an insightful, gifted astronomer. I also understood the pain of losing your grip on something you’ve worked hard on, something that feels like yours. It had happened to me. I might have invented transit transmission spectra, for instance, but dozens of astronomers have come along since and done more with it than I could. You can’t copyright an idea—all you can do is remember that sweet time when it was yours and yours alone. Then you have to let it go. You’re not the only one who’s allowed to look at rainbows.

  “You have to call NASA,” Cash said. I had to tell them that I didn’t want to be chair and wanted him to lead the study.

  “But I don’t. I want to lead it.”

  Cash lost his temper. He raised his voice at me over the phone. He couldn’t see that he already had his answer: NASA didn’t want him to lead the study. NASA knew what he could, and would, give them. They had seen his proposal, more than once, and they had rejected it each time. He couldn’t understand why, but they had to have their reasons. They wanted a fresh perspective, someone who knew what she didn’t know. They wanted me.

  “They want you because they know they can manipulate you,” Cash said. “They know you’re a pansy.” Click.

  A pansy, I thought. What a pretty flower.

  * * *

  ●

  Our first face-to-face meeting was scheduled for early July. It would be a two-day joint meeting of the two STDTs—the builders of the coronagraph and the shield. We would share the same foundations before we followed our separate pathways toward our collective dream of finding another Earth. Our days would be scheduled to the minute with lectures and brainstorming sessions. In addition to helping run the joint meeting, I would be given a half hour before lunch on the second day to present what I knew about the spectroscopy of super-Earths: thirty minutes to talk about my lifetime studying tiny, distant lights. I had a little less than three months to prepare to lead the Starshade team. I would do what I always did. I would read, and listen, and do the work.

  I decided the Starshade would be a new beginning for me. It was everything I loved in a machine—an extension of our best selves, an instrument, like a paddle, of forward progress, of our most human desires. More important, I felt it was our single best chance to take clear pictures of distant worlds. It might provide us with proof of other life that we could see, knowledge that we could hold in our hands as well as our hearts: We’re not alone.

  The Starshade could also slip into place between my past and my future. I had spent too long thinking about before; it was time for me to focus on the after. I figured that if our committee did our job as well as we could, we might be able to use the Starshade to explore as many as one hundred star systems in my lifetime—statistically, enough to see perhaps a dozen possible Earths.

  First, however, I had to steep myself in the Starshade’s byzantine, sometimes unkind history. Unfortunately, there are lots of reasons for complicated things not to work. Our critics have hundreds of years of error and tragedy on their side. Most of our greatest successes started with explosions. When you’re trying to do something that’s never been done, there are endless arguments for why it never will be. I can construct the mathematical case for other life, that there are too many stars for us to be alone, but the argument against this is still simpler, plainer: Then why are we?

  I told colleagues and friends about the Starshade. It was widely seen as that special kind of impossible—actually, irrevocably not possible. I heard the same message over and over again. Give up. Don’t bother. That’s a doomed idea, long past dead. I was at a barbecue for exoplanet scientists in the Boston area, and I was told repeatedly, between mouthfuls of hot dogs and hamburgers, why the Starshade could never work. (Scientists and social graces don’t often exist in the same environment, especially not with food readily available.) Two spacecraft flying in perfect formation tens of thousands of kilometers apart? A giant shield crafted to a precision measured in microns? Making stars disappear? Think about it, Sara. To them I had been asked to climb a mountain without a summit.

  There were rumors even within our team that we had been built to fail. I didn’t like to believe something that cynical, but a small part of me saw the logic. If we couldn’t come up with a workable solution, on time and on budget, then NASA would have the cover to shelve the Starshade forever: We put our best minds on it, and they couldn’t crack the code. It would be like voting for a political candidate just to prove how awful their proposals might be. We tried that, and it didn’t work. The other answer must be the right answer. The other answer would be the coronagraph, unless they, too, failed. Then our only end would be blindness.

  * * *

  ●

  For some reason, Max and Alex had decided that the front hall was the perfect place for them to wage lightsaber battles. (If two kids were ever destined for Star Wars obsession, they were mine.) They would raise their plastic weapons and, more often than I’d like, accidentally hit the pendant light hanging down from the plaster ceiling. The light would swing on its chain, looking as though it might fall down on their heads. Every time it happened, I thought: I have to do something about that. But I didn’t know what to do or how to do it, so it became just another job left unfinished.

  After one particularly cinematic duel, I decided that either a boy or the light was going to end up damaged. The boys were probably staying, so the light would have to go. I wasn’t going to call anybody to take down my light, either. If I was going to be a leader, I had to take the lead.

  It didn’t seem all that hard, apart from the apparent guarantee of electric shock and a fall off the ladder. I spoke to one of the Widows and took detailed notes, and I did more research online. I wrote out my usual meticulous, step-by-step instructions and went over them again and again until I felt confident in my quest. If logic and evidence failed me, I hoped I’d get lucky.

  I turned off the light. I got out the ladder. I climbed up, trying to ignore the way the floor creaked underneath me. I reached high over my head and took down the fixture—carefully unscrewing the necessary screws and more carefully disconnecting the black wire from the black wire and the white from the white. I climbed down the ladder and set down the light. Then I climbed back up the ladder. I took some electrical tape and wrapped it around the raw ends of the now-exposed wires, still dangling from the hole in the ceiling.

  I climbed down the ladder and admired my handiwork. The foyer was a little dark now—you would have thought I’d understand what happens when a light goes out—but the boys wouldn’t hit the pendant again, no matter how crazy their duels became. I had made the sort of small fix that could masquerade as triumph.

 
I felt so reduced. I felt so gigantic.

  CHAPTER 17

  Chance Encounters

  Sitting on the small plane bound for Thunder Bay, Ontario, I wondered why I had ever said yes. A long weekend away from the boys, and right before the first in-person Starshade meeting—one of the most important meetings of my life.

  I had agreed to talk at the Royal Astronomical Society of Canada’s annual general assembly. Normally I would have declined such an invitation, summer weekends being precious to me, but the RASC had given me so much. The first time I had looked at the moon through a telescope—five years old, my father standing beside me, my eyes wide—had been at a society party. Later, as a teenager and through university, I had attended nearly every Toronto branch meeting. So although I was days from flying to NASA’s Goddard Space Flight Center in Maryland to start trying to make the Starshade, I had a different commitment to meet.

  While I was in my bedroom packing for the trip, Alex had lounged on my bed, watching me. I couldn’t decide what to wear. “Sometimes it’s hard to choose,” I told him. “I don’t want to be too formal, because it’s supposed to be a fun gathering over a long weekend. But I don’t want to be too casual, because then it will look like I didn’t take the invitation seriously.” Alex looked at my closet and then at the clothes in my hands and nodded. “I get it,” he said. “Women have too many clothes, but not enough of the right clothes.” I laughed and savored the moment. Worrying about what to wear meant that my other worries had faded, even if for only as long as it took for me to pack my suitcase. I was doing okay.