Worlds Beyond Ours

Extending human habitability to outer space requires learning to live more carefully and sensitively as a species interlocked with others.

Scott Listfield for Noema Magazine
Claire Isabel Webb is a historian and anthropologist of science, and a 2020-21 Berggruen Institute fellow.

Consider a trio of moments of entangled spacetime:

Jan. 7, 2021, cyberspace and Washington, D.C.: A staggering 4,112 people die of the coronavirus in America, a new record. Elon Musk becomes the richest person in the world and reiterates his plan to leave Earth and start a colony on Mars.

Dec. 7, 1972, near-Earth orbit: The crew of Apollo 17, 18,000 miles from home and on their way to the moon, snap a photograph of Earth. Illuminated by the sun and nestled in the sable sea of outer space, the “Blue Marble” image becomes a resonant icon of humans’ dear and fragile life-filled planet. Earth’s denizens wonder: Are there other worlds beyond? Or is this the only example of life in the universe?

Nov. 7, 1957, Calcutta, India: Two prominent biologists, Joshua Lederberg and J.B.S. Haldane, meet for dinner. A month earlier, the Soviet Union had launched Sputnik I, the first artificial satellite to orbit Earth. Lederberg and Haldane determine that a thermonuclear bomb detonated on the moon would be visible to Earthlings, and it would be so destructive it would spoil the possibility of finding traces of lunar life.

Lifted from three interspaced epochs of the ongoing Space Age — the COVID-19 pandemic, the environmental movement and the Cold War — those moments reveal how terrestrial troubles are entwined with hopes of discovering life, and of living, beyond Earth. As dreams to explore the cosmos curl skyward, fears and anxieties particular to each moment raise doubts not only about humans’ longevity on our home planet, but also about how we might inhabit and sustain life on other worlds as space-faring explorers. If humans self-destruct through nuclear war, poison the planet by churning out carbon into the atmosphere or fail to control a deadly virus, such events would preclude us from existing on Earth, living long enough to communicate with possible extraterrestrial beings and venturing to other worlds we might discover to be habitable.

Thus, fears of terrestrial apocalypse animate pursuits for life and living beyond Earth. But conversely, imagining how life (including human life) might exist in an extraterrestrial context, and seeing the planet from outer space, has driven imaginations of Earth’s possible futures — both hopeful, course-correcting pathways, but also escapist fantasies of extraplanetary colonization.

Anticipations of worlds beyond Earth — places that might be (or might be made to be) habitable — are made possible by conceiving of Earth as both threatened and interconnected: The coronavirus’s march across the world reveals the viruses’ disregard for political borders, the environmental movement highlighted the fragility of the planet’s entangled life and the Cold War ushered in the concept of global nuclear disaster.

These threats have, in different ways, revealed how actions are never self-contained in global, networked systems. Each moment’s particular planetary anxieties — pathogenic, climate, nuclear — have animated and informed scientists’ pursuit of extraterrestrial life.

“Information on whether a complete lifecycle can occur in space would also have obvious implications for the feasibility of eventual colonization of space.”
—1979 Space Science Board

On Oct. 4, 1957, Sputnik I streaked across the sky. Touching off the “space race” between the United States and the Soviet Union, the satellite represented the opposition between democracy and communism. “Artificial earth satellites will pave the way to interplanetary travel,” the Communist Party’s official newspaper announced the following day, and “our contemporaries will witness how the freed and conscientious labor of the people of the new socialist society makes the most daring dreams of mankind a reality.”

Sputnik I was particularly visible from the southern hemisphere, where Nobel Prize-winning microbiologist Joshua Lederberg happened to be traveling. A month later, on his way back to Stanford University, where he taught and researched, Lederberg passed through Calcutta to visit his friend and collaborator J.B.S. Haldane. Haldane had formulated the “primordial soup” model — how life could have originated from abiogenic materials on an ancient Earth. Both scientists looked forward to that night’s lunar eclipse.

Over dinner, Haldane — a “confirmed Communist” and “radical alternativist,” according to Lederberg — “gloated” that it was also the 40th anniversary of the October Revolution, the event that had precipitated the formation of the Soviet Union. As a thought experiment, the two scientists wondered: What if the Soviets leveraged the symbolic occasion to plant a “red star” — a nuclear bomb — on the moon? Their back-of-the-napkin calculation revealed that it would be visible from Earth.

Of course, there was no “red star” that evening, and the U.S. astronauts of the Apollo 11 mission, not Soviet cosmonauts, would be the first to land on the moon twelve years later, in 1969. But the conversation with Haldane about the possibility for off-Earth atomic destruction spurred Lederberg toward the study of “exobiology,” the search to detect and preserve life beyond Earth. As the U.S. and the Soviet Union’s space race accelerated during the Cold War, the National Academy of Sciences established the Space Science Board (SSB) to research outer space and to recommend policies to NASA. That group, which included Lederberg and other prominent scientists (among them a young Carl Sagan), worked to protect the moon and other extraterrestrial sites as scientific laboratories.

Looking ahead to possible NASA missions that would explore Mars and Venus for traces of life, a 1959 SSB report that Lederberg chaired transported Cold War fears of nuclear war on Earth to celestial bodies beyond. It warned that “the effect of introducing radioactivity on another planet where there may be entirely different levels of background radiation from those found on Earth could greatly influence any form of life found there.” Planetary concerns of atomic fallout migrated to unexplored sites beyond our planet.

In addition to nuclear radiation on other planets, the possibility of microbial contamination presented risks in the search for life beyond Earth. A spacecraft landing on Mars, for example, might bring terrestrial hitchhikers, risking a false detection of organic biochemistry that would muddle attempts to theorize the origin of life in the solar system and possibly the cosmos beyond. Throughout the late 1950s and the 60s, exobiologists’ reports urged sterilization protocols be taken so as to preserve possible “planetary biota” on Mars.

At the same time, exobiologists worried that possible Martian microbes might infect Earth; through incautious activity by either the U.S. or the Soviet Union, a “dramatic hazard would be the introduction of a new disease, imperiling human health,” as Lederberg wrote in 1960. This particular threat took center stage in Michael Crichton’s 1969 science fiction book (and subsequent film) “The Andromeda Strain,” in which a mysterious and fatal extraterrestrial microorganism appears in Arizona and threatens to end life on Earth. Merging apocalypses, the characters consider annihilating the infected laboratory with a nuclear bomb.

Civilian scientists’ goals to detect extraterrestrials were often at odds with those of the national agencies they answered to. While John F. Kennedy’s 1962 “We choose to go to the moon” speech mandated the priority of manned missions to outer space that would showcase national prestige, exobiologists advocated for international efforts to preserve (extra)terrestrial life forms. A 1961 SSB report suggested that the U.S. and the Soviet Union work together on sterilization protocols to “simplify the problem of protection against possible contamination of the planets and of the Earth.” The planetary struggle for political dominance, which threatened to plunge Earth into a nuclear apocalypse, was thus shaping extraplanetary pursuits.

As they considered Earth and extraterrestrial sites of possible life (Mars’s subsurface, Venus’s atmosphere and even, possibly, the moon’s dust) in tandem, exobiologists began to imagine interconnected, but distinct, planetary wholes. Linking Earth to planets beyond, two exobiologists wrote in a 1961 report, “The planets of the solar system are part of a whole — in their origins, in their present states and in their futures.” Such exercises that forecasted other worlds soon came to intersect with growing concerns about the fragility of our own planet.

“Musk has reshuffled space exploration: individualism over nationalism, money power over patriotism, the adventure or even salvation of the few over the many.”

Amid the persistent threat of nuclear apocalypse that defined the Cold War era, exobiologists began to call for planetary protection protocols for both Earth and extraterrestrial sites — concerns that became increasingly aligned with a burgeoning consciousness about humans’ harmful activities on Earth. Rachel Carson’s 1962 book “Silent Spring” introduced the idea that synthetic chemicals, especially pesticides — which she argued should be called “biocides” — were fundamentally altering life on Earth. The ensuing environmental movement of the 1960s and 70s culminated in the creation of the U.S. Environmental Protection Agency and made “the environment” a widespread public concern, fortifying the concept that life systems were interconnected, malleable and fragile.

Stewart Brand’s “Whole Earth Catalog” often advocated for ecological issues and featured images of Earth from space on its early covers, from a mosaic made of satellite photos to Apollo 8’s “Earthrise.” Images of Earth from outer space cast it as a planetary whole, one that was both precious and under increasing peril. From above, the planet’s dynamism and liveliness, found in swirling white clouds layered over placid blue oceans, was contraposed to the Stygian blackness of space. The void circumscribed and encircled Earth, framing it as an enclosed and lively gem.

Apollo 11’s “Blue Marble” photograph especially embodied the environmental movement’s push to consider the Earth as an entangled system whose longevity should supersede politics and profit. As the scholar Sheila Jasanoff put it in a 2001 paper, “subordinating as it does the notional boundaries of sovereign power in favor of swirling clouds that do not respect the lines configured by human conquest or legislation,” the Blue Marble image became a “fitting emblem of Western environmentalism’s transnational ambitions.”

“Will humans transport terrestrial troubles to outer space?”

For biologists exploring the conditions and contexts of life beyond Earth, the planetary whole constructed by these images was fertile ground for theory and experiment. Take James Lovelock and Lynn Margulis’s Gaia theory, which articulated the idea of Earth as a self-regulating organism. Later, in the early 1990s, the Biosphere 2 project in Arizona created a closed ecosystem of various biomes (among them, mangrove, rainforest and savannah) meant to simulate the construction of habitable environments in future missions to colonize other planets.

In a 1979 SSB report, scientists drew inspiration from Earth’s interconnected biosystems as they sought to understand how life might function not only in the closed environment of a spacecraft, but also on other worlds that humans would colonize. Seeking to approximate “the only ecological system that is certainly self-regulating” — that is, “Earth itself” — the scientists struggled to transport what they viewed as the overwhelming complexity of intertwined factors (species adaption, variation in temperature, reaction to stress) to the environment of a spacecraft.

To tackle what they called the “ecological uncertainty principle,” the scientists recommended a completely closed system that mixed “natural” components (Earth’s gravity, atmosphere, an environment that would produce complex molecules) with “artificial” ones (human control, forced adjustments to chemicals). As they put it, “The appropriate conceptual picture of a space station is an array of separate apartments for vegetation, animals and humans for chemical processes, each with its own optimum light, temperature and atmospheric requirements, but with interconnecting links and storage facilities.” Predicting how mammals would thrive and even reproduce in space, the report suggested that such research would have “obvious implications for the feasibility of eventual colonization of space.”

The Earth as a self-regulating organism was a blueprint not only for how to imagine spacecraft, but for how to imagine (extra)terrestrial worlds as well. The concept of “Spaceship Earth” — a term popularized by American author and inventor Buckminster Fuller — described the planet as a confined and sensitive biological system, bearing passengers from humans to microbes who depended on its continuity as they braved the sea of space. Could Spaceship Mars soon join this planetary fleet of life?

“‘It is possible that on Mars there are pathogens, organisms which, if transported to the terrestrial environment, might do enormous biological damage.’”
—Carl Sagan

When Tesla stock surged in January this year, the company’s CEO (and SpaceX founder) Elon Musk surpassed Amazon’s Jeff Bezos to become the richest person in the world. Now worth $195 billion dollars, Musk pinned a past tweet to his account as pro-Trump insurgents stormed the U.S. Capitol building:

That a single billionaire imagines he might divide his personal fortune to ameliorate terrestrial problems and establish an extraterrestrial colony speaks not only to the staggering inequalities wrought in the maw of late capitalism, but also to the ideological shifts in how humans have approached space exploration since the Space Age. If Lederberg and Haldane represented divergent political paradigms of the Cold War era, yet nonetheless sought to engage their international colleagues for basic science research, Musk’s SpaceX has reshuffled the hierarchies and priorities of space exploration: individualism over nationalism, money power over patriotism, adventure or even salvation of the few over the dreams of the many.

Late capitalism’s increasing privatization and commercialization of space promises off-world living to the uber-rich. SpaceX, which bills itself as building “the road to making humanity multiplanetary,” is testing and perfecting the “Starship” spacecraft to take private passengers to Mars by 2026. Commercial flights that would flirt with the lunar orbit might cost tens of millions of dollars. SpaceX and its ilk — Richard Branson’s Virgin Galactic, Jeff Bezos’s Blue Origin — could provide vehicles to leave a troubled or toxic planet to colonize Mars or, later, some Earth-like planet beyond the solar system.

Hatched in the Anthropocene to “solve” apocalypses, such survival projects are what anthropologist David Valentine calls “exit strategies”: neoliberal, capitalist-driven projects that seek to make space profitable and to establish off-world colonies — havens from the perils of Earth. Yet they raise the question: Will humans transport terrestrial troubles to outer space?

Plans to privatize space are becoming a reality as a third new specter of peril, the novel coronavirus, rips through global health systems, disproportionately sickening and killing those already more vulnerable. More than 2.4 million people have died so far, and recent mutations are further complicating global efforts to control its spread. Thwarting national borders, the virus is a leaky and fluctuating problem that demands planetary cooperation.

Past apocalypses are colliding with the present: Fears of dying from a potent microscopic virus recall exobiologists’ anxieties of decades past that previously latent alien microbes might colonize the lush environment of Earth and end life as we know it. Looking ahead to the Viking missions that would explore the surface of Mars, Carl Sagan wrote in 1973: “Precisely because Mars is an environment of great potential biological interest, it is possible that on Mars there are pathogens, organisms which, if transported to the terrestrial environment, might do enormous biological damage.”

In another recapitulation of apocalypses past, Musk has laid tentative plans to bring atomic bombs off-world, terraforming Mars to transform its environment for human habitability (a plan that NASA has dismissed). In response to challenges to his “Nuke Mars!” tweet in 2019, Musk indicated he would need 10,000 atomic bombs to thaw the planet’s ice caps. Doing so, he predicts, would trigger the release of greenhouse gasses that would create an atmosphere, and solar reflector satellites would heat the planet.

“In response to challenges to his ‘Nuke Mars!’ tweet, Musk indicated he would need 10,000 atomic bombs to thaw the planet’s ice caps.”

Also consider Musk and geneticist Craig Venter’s plan to print bacteria and other organisms on Mars to aid this process; others have suggested that microbes would be “primary colonists and assets, rather than serendipitous accidents, for future plans of extraterrestrial colonization.” Projects to establish human life off-world, now, have inverted historical fears that nuclear bombs and microorganisms would destroy (extra)terrestrial life. Instead, they have been reimagined as tools to make other worlds habitable.

That future of life is far from guaranteed. A recent astrophysics paper postulates that even while simple life forms in the Milky Way are probably common, the emergence of one technology-using species will be tempered by another’s self-annihilation: birth and death in a cosmic equilibrium. Here, the concept of the self-regulating biosphere of Earth, in which life is maintained in homeostatic balance, extrapolates to our galaxy.

Strange resonances continue to animate the concepts of annihilation, interconnection and escape here on Earth. The coronavirus moves from host to host, shadowing human plans to create enclosed biospheres (spacecraft, glass domes) to sustain life as we travel through space. Russia named its COVID vaccine Sputnik V, pointing like its namesake to power gained through science and technology. The conception of Gaia, a self-regulating biosphere, propels a sense of interdependence between Earth and the greater cosmos. Now, billionaire kings of our techno-capitalist society reimagine terrestrial assets, both monetary and organic, to aid their fantasies of escape off-world.

Hopes for human futures — both on Earth and off — represent not only an enduring projection of space, but a projection of time. Extending human habitability to outer space requires learning to live more carefully and sensitively as a species whose longevity is interlocked with others. The planetary and the extraplanetary remain in ongoing conversation and negotiation as they continue to redefine what life is on Earth, and what it could be in worlds beyond ours.