Carl Sagan’s novel is an unexpected lesson in faith.

“As I imagine it,” Carl Sagan once said, “there will be a multilayered message. First there is a beacon, an announcement signal, something that says, Pay attention. This is not some natural astronomical phenomenon. This is a signal from intelligent beings … Then, the next layer is one that says, This message is directed specifically to you guys on Earth. It isn’t directed to anybody else. And the third part of the message is the real content, which is a very complex set of data in a new language, which is also explained.”

He was describing his novel, Contact, a 370-or-so-page answer, literally or in spirit, to every question we can ask about how finding alien intelligence might go. Yes, there’s conflict and strife—acts of terrorism, government obstruction, frustration and loss and death—but at its core the story promises an inviting cosmos. A door opening to a galactic community. We’re not only not alone but also welcomed. This hope is central to the idealistic origins of the search for extraterrestrial intelligence (SETI), to Sagan’s motivations as a scientist and communicator. It also makes it especially weird that the novel ends with its heroine finding proof that God is real, but we’ll get to that.

The heroine of Contact is Eleanor Arroway, a SETI researcher whose observatory receives a signal coming from the star Vega. It’s a string of prime numbers, indisputably unnatural. Beneath the beacon of the prime numbers, the signal is decoded to be a rebroadcast of Hitler’s 1936 Olympics address—the first Earth transmission made at a high enough frequency to slip through the atmosphere. (Sending Hitler back to us turns out to mean Hi, we got your transmission, but it’s certainly alarming at first.) Buried beneath that video is what comes to be called the Message, which contains instructions for building a Machine. No one knows what to expect when the Machine launches on New Year’s Eve in 1999. To outside observers, it spins for 20 minutes and then stops; but the travelers onboard—including Ellie—experience a much longer trip through a series of wormholes to the center of the galaxy, where the senders of the Message await.

Nowadays, SETI researchers offer far less fantastical possibilities, reframing their search not as one for messages or signals but for technosignatures—such as Dyson spheres or a radio signal leaking out from an alien transmitter. But Sagan and his generation of the first SETI pioneers were looking for a capital-M Message in their nonfictional lives too.

SETI as a scientific discipline was born in the aftermath of World War II, at the dawn of the Cold War. Humanity was newly possessed of the power to truly destroy itself, and the detonation of two atomic bombs in war had not taken our fingers off the button. A signal from an advanced alien civilization would be proof that advanced civilizations could exist, could survive their own technological power and thrive. And maybe, Sagan and his colleagues hoped, whoever was out there would know that a nascent technological power needed help, in the form of technology or advice or something we couldn’t even imagine.

In Contact, the Machine and the journey its passengers take are not the life raft. The life raft is the Machine’s construction on Earth. “In a world gingerly experimenting with major divestitures of nuclear weapons and their delivery systems, the Message was taken by whole populations as a reason for hope,” Sagan writes. “For decades, young people had tried not to think too carefully about tomorrow. Now there might be a benign future after all.” The Message is icing—it would be enough just to know someone is out there.

Jill Tarter, the SETI scientist on whom Ellie Arroway is sometimes said to be based, believes SETI offers hope, too, that the power is in the search, not the discovery. She told me, “Our ability to do these searches has the effect of holding up a mirror to a human and saying, Look in that mirror. Compared to something else out there, you are all the same. We humans are all the same.” Whether our looming fear is nuclear winter, climate change, or some other civilizational end, we hope for something or someone to shock us out of our inaction.

Ann Druyan calls this thing that SETI might give us “human self-esteem.” Druyan was married to Sagan from 1981 until his death in 1996, and she told me that, among their many collaborations, she co-wrote Contact. (Only Sagan’s name appeared on the book, but Druyan is listed as a producer of the film Contact and credited alongside Sagan for the story.) Druyan’s “human self-esteem,” that ephemeral enlightenment, is at the heart of Contact, more meaningful in the end than technological advances or cosmic journeys.

During Ellie’s journey in the Machine, the aliens give her almost everything she could hope for, save proof of her story to bring back to Earth. Ellie wants a taste of information about the cosmos, the aliens, everything she doesn’t know. But what the aliens really offer is a mirror. That’s what Sagan offers the reader, too, hoping that some fraction of what real contact might do to humanity could be communicated through fiction.

“You humans have a certain talent for adaptability—at least in the short term,” the alien tells her. But, he concedes, “you can see that, after a while, the civilizations with only short-term perspectives just aren’t around. They work out their destinies also.

It’s not a grim prediction so much as a warning. And the alien does offer Ellie inspiration as well, with a view of the vast work ancient civilizations are capable of across the universe. He tells her of a collective of many galaxies engineering the cosmos. “You mustn’t think of the universe as a wilderness. It hasn’t been that for billions of years,” he says. “Think of it more as … cultivated.” But even these gardeners and architects are not the most powerful, or the most ancient, beings in the universe.

There always needs to be someone older or more powerful, it seems. Some mystery. The Star Maker behind the curtain. The builders who, billions of years ago, ran off to no-one-knows-where, if where even applies. We’re left with artifacts and clues, scraps of messages and wonder.

Ellie asks the alien to tell her about his myths and religions. “What fills you with awe? Or are those who make the numinous unable to feel it?” And so he tells her about pi. And this is where, it seems to me, we’re being told that God exists. The alien tells Ellie there’s a message in binary hidden in pi, and when she gets back to Earth, she sets an algorithm to deciphering it. On the very last page of the novel, her computer finds an anomaly in pi when expressed in base-11, a sequence of ones and zeros that, when printed out on a grid, reveals a perfect circle. “The galaxy was made on purpose, the circle said.”

At first thought, I find it extraordinarily strange that Contact, a book about the power of scientific inquiry as a source of awe and self-discovery, would end with proof that God is real. Not the God of Jesus or Abraham or anyone else, but some creator, some Star Maker who embedded a message in math. Ellie’s journey, though she is an atheist, is one of faith—her SETI research is motivated by a belief in something bigger beyond Earth; upon her return, she has no proof aside from experience of the journey.

But maybe faith in the numinous by way of alien contact isn’t so distinct from proof of the intentional creation of the universe. Druyan told me, “It’s the laws of the universe as a kind of holy, sacred thing … Not punitive, not judgmental, not telling you what to eat or who to love. But the idea that the laws of this universe are knowable … There is something sacred in discovering these laws.”

By expanding our sense of the scope of the world, science fiction and fantasy “have the same central function as myth and theology,” writes Ryan Calvey in his doctoral thesis, “Transcendent Outsiders, Alien Gods, and Aspiring Humans.” As the anthropologist John Traphagan points out, “It is no accident that SETI arose in a cultural context heavily shaped by Christianity and its inherent assumptions about the existence of a higher being.” In Contact, the alien offers Ellie not just knowledge and information but a benevolent attention focused on humanity, offering us a small nudge in the direction of peaceful survival. Even if our worldview doesn’t include God, we want to be able to see ourselves through his eyes. For context, for insight, but also to know we’re okay.

Despite our decades of technology and centuries of civilization, we are children in the gaze of these beings. But there’s something reassuring about that; it’s the same as how I still want my mom when I’m sick. If we’re children, then our mistakes are just the messy path of learning; if we’re children, the grown-ups can still come and help. We don’t want this violent, greedy, suffering version of humanity to be our final form. Transcendent outsiders give us hope and, hopefully, guidance. But even just knowing they are out there—and that they are reaching toward us—could be enough to change the world.

This article has been excerpted from Jaime Green’s new book, The Possibility of Life: Science, Imagination, and Our Quest for Kinship in the Cosmos.