by Sarah Scoles
But radio waves, like car headlights, dim the farther they travel into the distance. And signals from space have generally journeyed trillions of miles before they get to us. They arrive weak, in need of assistance. SETI scientists don’t want to miss the alien signals simply because the telescope wasn’t sensitive enough, the broadcast too bedraggled, the civilization too far away. So a circuit that Tarter’s husband, Jack Welch, designed, amplifies the signal. Welch’s amplifier circuit makes message-finding possible. The couple have been working on the ATA design together at their dining room table for years. Welch’s notebooks and papers are always piled up, pushed aside for dinners.
“Do you think it would change people’s day-to-day lives if we found a message from extraterrestrials tomorrow?” Tarter asks. “I wonder,” she continues, nodding to herself and walking toward the green-alien doormat.
Back inside the control building, someone has taped a piece of paper with a printed gremlin on the server room door. Its impish gaze follows as Tarter opens the door. Inside, racks of computers hum and heat the air. A/C units do their best to keep the temperature at a cool equilibrium. The room has more optical fibers and wires—plugged from this into that, and from that into something else—than a Radio Shack warehouse. They are thick, thin, bundled, loose, curving, dangling, sagging, taut, blue, orange, purple, green, yellow, red. They have invaded. Tarter slips around the Medusa’s head of wiring.
At the back, the processing systems have labels: PRELUDE, SONATA, and FOXTROT. She shakes her head at the latter one and mutters, “IT guys,” under her breath. In the early days of SETI, those guys custom-built every bit of this hardware and software. Bespoke may be cool for fine Italian suits, but scientists would prefer it if they didn’t have to make their own equipment. Today, consumer technology is finally powerful enough that SETI can steal it (just as the SETI 2020 technologists predicted). When Dell, through vice president Forrest Norrod, and Google donated ultra-fast servers for the ATA, the SETI Institute finally got to throw away the ones they’d spliced together.
But certain parts are still custom tailored, like a piece of hardware labeled BEAMFORMER, which allows the telescope to zoom in on specific exoplanet systems and search them for intelligent inhabitants in real time. (Extraterrestrial broadcasts, like our own, might turn on and off. If the ATA picked up a “Hello, Earth” broadcast on July 10, 2014, but no one noticed for a week, the interstellar show may have ended already.) The SonATA software figures out which distant worlds the ATA can see (its view spans, at any given time, a patch of sky as wide as five of our full moons), and homes in on three of them at once, looking for broadcasts that occur at a single frequency, like our radio stations.
In this fluorescent-lit room filled with fiber and fans, a computer program searches autonomously for evidence of extraterrestrial life. Normally, this search runs itself, and this room is empty. But today, the room’s blinking LEDs reflect off Tarter’s jewelry, bouncing like a beacon from the turtle pinned to her earlobe.
Back in the control room, Tarter flips open her MacBook Pro, which somehow stores more files than most people create in their entire lives. She navigates to a website called SETIQuest, which shows the ATA’s progress: how many planets it’s searched for signs of smart life. On one page, a GIF of Inspector Clouseau, tapping his fingers in impatience, pops up. When observations start up again, the detective disappears and a buxom woman takes his place, peering back and forth with binoculars. Jon Richards, who wrote the software that runs the telescope and also, usually, runs the telescope, created the page and chose the animations. “Each of us has our job to do,” says Richards. “Mine is to keep the signal search going.”
That’s kind of the most important SETI job at the SETI Institute. And so he gets to design the webpage and make animated GIF jokes if he wants to.
Tarter sighs. “I’ve been thinking we should age the woman,” she says. And, indeed, Richards later upgraded the website, giving it new interactive features that allow viewers to follow along and access real data from the day’s observations. Buxom women (of any age) and French inspectors have disappeared.
Astronomers have confirmed around 3,500 planets as of January 2017, and they have thousands more candidates awaiting confirmation. When the ATA points at these exoplanets, collecting whatever radio waves may be coming from their direction, the software scans 9 billion different radio channels in search of an alien signal. Each of these channels is a tiny slice—a single station—of the ATA’s “radio dial.” Scrolling through all the planets and all the frequencies will take at least five total years of dedicated time.
The list on the site displays worlds upon worlds, like some kind of yearbook full of strangely named students: Gliese 581, Kepler 69, 51 Pegasi. Which is the most likely to succeed?
Each target gets 90 seconds in the spotlight. If SonATA doesn’t see anything that looks suspicious, it moves on to the next candidates. But if something catches its attention, it halts, about-faces, and assesses the likelihood the rogue radio waves come from ET. Has this particular signal ever shown up before? Is it coming from just one place in the sky? If so, SonATA checks the planet again—and then three more times—before any humans find out. If any signals survive those five trials, SETI scientists’ cell phones ring and beep with text messages.
The responsible researchers log in from offices or bedrooms to continue to follow up the signal. If it persists, they drive up to Hat Creek. They then check the signal themselves and must withhold judgment (and celebratory Champagne, which sits always on ice) until they’ve run out of tests or the exoplanet begins to slink below the horizon. If the signal still looks promising, the scientists phone another observatory, begging the director for “discretionary” time—emergency follow-up observations that don’t have to go through the usual lengthy process of approval. Do they see that same signal? Does it look like a message from intelligent beings?
They have gotten that text message exactly once. And the signal, as usual, turned out to be just evidence of us.
That evening in March 2014, Tarter drives to the nearby Burney Falls, one of her favorite local views. She walks down the Conservation Corps’ stone stairs. Just like this is a family vacation, she stops at each interpretive poster, learning about the volcanic dynamics that shaped this region. At the falls, which dump 100 million gallons of water over their edge every day, she observes in silence. It is beautiful: a cascade pouring over a wall of basalt and through the many holes in the rock. Tarter points all the way across the gorge to a tree that towers over the whole scene.
“There’s a nest up there,” she says. She proceeds to wonder what type it is and whether the raptor ominously riding air currents lives there. Such speculation normally is idle: wonder, move on, and forget. But when the ranger’s office opens the next morning, Tarter calls to inquire about this bird’s species: a bald eagle.
She wants to understand birds’ nests and lava formations just as she does fast Fourier transforms and Nyquist sampling. On some rocky Earth-twin world a few hundred light-years away, perhaps a bizarro Burney Falls exists, formed by that planet’s own fiery interior and bored through by the relentless flow of water. Perhaps she is thinking about that.
Perhaps she is not. Maybe the world around her is satisfying on its own, right now.
That night, a few thousand stars again are visible. It’s impressive, but at least a hundred billion more are out there, in our galaxy alone. Astronomers now estimate the Milky Way is home to at least 100 billion planets, too. And as Contact aphorizes, if there’s nobody else out there, “that seems like an awful waste of space.” But it’s precisely because space is so big that the search for extraterrestrial technology is so hard and uncertain. Tarter may hope, every time she pulls out her iPhone to consult a celestial map, that an alert from SonATA will pop up. She may wish that the software would summon her colleagues, gathering them back to the Hat Creek control room to white-knuckle through the confirmation protocol. But she knows, and they all
know, that with the universe’s nearly limitless possibilities, the call could come in 10 years, tomorrow, next month, or never.
Perhaps with the telescope’s new receiver upgrade, slated for installation in late 2015 and being constructed in Antioch, California, the ATA will find aliens whose home lies much farther away.
CHAPTER 4
THE FUTURE OF THE ALIEN-HUNTING TELESCOPE
Antioch is the home of the milk carton. In the 1950s, visionaries at Fibreboard Research Company figured out how to apply wax coatings to cardboard containers, saving schoolchildren everywhere from dairy products that taste like paper. Now, however, Antioch is home to another innovator: Minex Engineering Corporation, which creates precision parts for the Allen Telescope Array.
Minex lives next to a property management company, at the end of an office park cul-de-sac called Apollo Court. The yellowish-gray industrial siding and single unadorned glass door make you think this must be a different Minex. Not the Minex where people develop the technology to find ET, but maybe the Minex that does your taxes or mails packages for you.
But it is at this Minex that engineers are currently working on the upgrade that they hope will make the ATA’s vision twice as good. Instead of building more antennas, the team are making the existing antenna better. They designed a new “feed”—the pyramidal part that turns the radio signal into data humans can understand.
Inside this pyramid, the air is a hyper-cooled vacuum. The colder that vacuum is, the less the atoms in the electronics move, and the stiller they stay, the less they interfere with scientific signals. The upgraded feed will have a similar pyramid but finer electronics and will live within a larger vacuum chamber. In other words, everything will be colder and quieter, and the telescope will be able to pick up weaker signals from space because it won’t be making as much of its own noise.
If the team can successfully grow and transplant this new organ into the 42 antennas, each antenna will become twice as good at its job. But in July 2014, when the Minex engineers meet with some SRI International staff to update them on the progress, it doesn’t look good. The upgrade is over budget and off deadline, and the warehouse is 95 Central Valley degrees. The whole project might be impossible.
Inside Minex, Welch awaits the beginning of the meeting. He sits asleep at the reception table, which is just a card table in the middle of a square, white-tiled room. A notebook of hand-scrawled calculations lays open on the table next to him. The inner door swings open as two men, Minex engineers, walk into the lobby. The brief gap between door and wall gives a glimpse of CNC millers, anechoic chambers, wave solderers, and other jargony devices that look like someone might actually create telescopes here. The men wear jeans and name-emblazoned work shirts. Matt, one says. Brad, claims the other.
“Jill here?” they ask.
Welch does not wake up at the mention of his wife’s name. His head still rests against the chair; his hand still sits limp against his logbook.
“I don’t see any SRI guys,” Matt says.
He retreats to the back room. I follow. Against the far wall, a large shipment of molded plastic languishes. The brown, columnar molds look unambiguously phallic, all lined up and ready for action. This high-tech plastic, usually used for fighter-jet components, was supposed to sheath the antennas’ new insides. This foray into the world of exotic plastics came about when the price of fused quartz glass, the material initially proposed for the vacuum jars, jumped radically after funding was obtained. The molds let radio waves pass through but seal off air from the outside world, maintaining the ultra-cold vacuum inside. Matt picks one up and explains that the material outgasses, meaning that tiny molecules leak from its sides. Matt and the others tried painting a seal on, but that didn’t work, either.
Above the shop hangs a thematically relevant fighter-jet calendar and a less on-topic fast-car calendar. A wheel-bottomed organizer houses drawers labeled !!! DON’T TAKE IT; PARTS, NOT CLEAN; and LOCTITE KRYTOX, which sounds like an alien language but is actually a type of lubricant.
Just as Matt puts the phallic plastic back where it belongs, Tarter walks in, husband trailing behind her. Sunglasses still shade her eyes, and red toenail polish peeks through her sandals. She brandishes an email she sent earlier that morning. Subject line, straightforward as a For Dummies manual: “Charts that help me think about what we have achieved.” The body of the message has the structure of a scientific paper: a list of six charts, an observations section, questions for discussion, and conclusions. The charts show how the electronics inside the updated feed should perform compared to the old model, as well as how they actually do perform. The new instruments will be sensitive to a whole range of high frequencies that the old instruments could not detect at all—and more sensitive to even the lower frequencies the old ones could detect. The upgrade will give them access to parts of the spectrum—and so potentially to alien broadcasts—they could not have seen before, and will let them pick up fainter messages of all stripes.
“Everybody here?” she asks.
The SRI guys meander in shortly after. They wear suits and have clean-lined haircuts.
“We’re all here,” they say.
The gist of the engineers’ presentation is this: the upgrade is all wrong. There’s the outgassing, sure. But atoms also leak into the vacuum. And the system slowly warms up over time. They have no idea why.
“Dark matter,” Tarter mumbles. It’s a sort of joke. It gets a laugh from a young guy who appeared out of nowhere and hovers silently in the back with his arms crossed over his half-tucked-in silk shirt.
If they can’t fix the fighter jet plastic, Matt says, they’ll have to use glass covers. These covers are pretty and more reliable, but expensive—just like a glass bottle merits a greater return from the recycling bureau than a plastic one. And on top of the extra money for the material itself, there’s the difficulty of making the pyramid’s tip super thin—just 40/1000 of an inch. No company thinks the delicacy required to make a glass pyramid that thin is worth it, not even for a lot of money.
“How thin will the company agree to make it?” Tarter asks.
“Sixty thousandths,” Matt says.
Tarter turns to Welch. “How much signal do we lose if we accept that thickness?”
Welch consults his notebook. “Five percent,” he says.
“On top of what you lose already by having forty thousandths?”
“With forty, you lose three percent,” he says.
“So, we’d lose an extra two percent,” Tarter counters.
“Well, you’d lose five percent total.”
Tarter sighs and says, “Okay.”
The engineers shift their weight and look around at each other. Their colleagues sometimes have separate meetings with Tarter and Welch, so they can relay information between the spouses, rather than having the spouses spat.
Later, Tarter and Welch will have an argument about which electrical component company makes some electronic component.
“Hittite,” Tarter will say.
“Right,” Welch will continue, “those Hitachi things.”
Tarter worries that Welch’s memory is slipping. She sometimes lashes out in frustration, picking little fights about the inconsistencies, or shaking her head and correcting him. In his potential slippage, 10 years biologically ahead of her own, she sees her future—and fights against it. She tries trying to force him to remember “Hitachi,” as if by doing so she can ensure she will remember it when she is 80.
“Never get old,” she says to me, often.
But the engineers have already left the familiar marital bickering behind and moved into a discussion of electronics: the feed’s low-noise amplifiers. These boost the signal, essentially turning up its volume. Matt lays pages of price quotes out on the lab table. The comparisons come from a place called the Low Noise Factory, suggesting an underworld market invisible to the outside world. Trouble, though, is also afoot with the amplifiers. Neither of the two options performs
as well as they should when they attempt to amplify radio waves at higher frequencies.
Tarter places her hands on the table in front of her, her head hanging down. After a few seconds, she sighs and looks up. “We have to have feeds at some point,” she says. She gazes around at the crowd, who are silent.
“Really,” she continues. “We have to have feeds. At some point.”
But the thing is, they don’t. There’s no guarantee the SETI Institute can make the feeds work as planned, just as there was no guarantee they could build 350 antennas, which they haven’t so far. Given the time delays, the budget overruns, and the failure of most feed components to behave like they’re supposed to, one has to wonder if the ATA and its upgrade will turn into SETI’s version of Boston’s Big Dig. How far should they go, and how much money should they spend to make this particular telescope happen? It’s not like it would be first failed or canceled scientific instrument—the Superconducting Super Collider, the Tevatron. You never believe your scientific instrument will be the one to fail, but somebody’s has to be.
But, so far, no one at the institute has yet thrown their hands up or the towel in on the ATA upgrade. And the team decides, months later, to go with the glass covers. They accept the slightly muted radio waves. And a few months later, they solve the temperature and amplifier problems. By the summer of 2016, they have finished designing and have started installing new feeds—10 in total. Things start to look up. Although they then ran out of funds to complete the installation, an influx in September will bring the total to 20—nearly halfway there. Tarter and Welch, in August, sold their share in the small plane they co-owned with two young partners and donated the money to the telescope’s improvement.