This week the planet Mars will be low in the western sky for an hour or two after sunset. It’s visible only as a pale, ruddy light, hardly distinguishable from the few stars that start blinking on in the night sky as the dusk deepens. You may notice, however, that its tiny flame burns steadily, more steadily than that of any impossibly distant, impossible-to-touch star. Once you find it, you may not want to look away.
For more than a century now, the fourth planet from the sun has drawn intense interest from those of us on the third. We viewed it, first, as a place where life and intelligence might flourish. The mistaken identification of artificial water channels on its surface in the late 19th century seemed to prove that they did. More recently, terrestrials have gazed at the arid, cratered, wind-swept landscape and seen a world worth traveling to. With increasingly intense longing, we’ve now begun to think of it as a newfound land that men and women can settle and colonize. It’s the only planet in the solar system—rocky, almost temperate, and relatively close—where something like that can be conceived of as remotely plausible.
Since the last moonwalk, in 1972, Mars has drawn the fitful attention of American presidents and blue-ribbon commissions. As the Apollo program was winding down, Richard Nixon declared, “We will eventually send men to explore the planet Mars.” During the Reagan Administration, the National Commission on Space, chartered by Congress, proposed actual dates: a return to the moon by 2005 and a landing on Mars by 2015. President George H. W. Bush declared “a new age of exploration with not only a goal but also a timetable: I believe that before Apollo celebrates the fiftieth anniversary of its landing on the Moon, the American flag should be planted on Mars.” That would have been in 2019. George W. Bush came up with yet another set of dates. He renewed the call to extend “human presence across the solar system, starting with a human return to the Moon by the year 2020, in preparation for human exploration of Mars and other destinations.”
In 2010, Barack Obama rejected Bush’s plan to go back to the moon, canceling the Constellation program and the heavy-lift Ares rockets that would have taken astronauts there. In his reboot of the human spaceflight program, Obama said, “we will start by sending astronauts to an asteroid for the first time in history,” by 2025. He added that “by the mid-2030s, I believe we can send humans to orbit Mars and return them safely to Earth. And a landing on Mars will follow. And I expect to be around to see it.”
A half-century after the conclusion of the Apollo mission, we have entered a new age of space fantasy—one with Mars as its ruling hallucination. Once again stirring goals have been set, determined timetables have been laid down, and artist’s renderings of futuristic spacecraft have been issued. The latest NASA Authorization Act projects Mars as the destination for its human spaceflight program. Last month’s successful test flight of the Orion space vehicle was called by NASA Administrator Charles Bolden “another extraordinary milestone toward a human journey to Mars.” The space agency’s officials regularly justify the development of new rockets, like the Space Launch System, as crucial to an eventual Mars mission.
But human beings won’t be going to Mars anytime soon, if ever. In June, a congressionally commissioned report by the National Research Council, an arm of the National Academy of Sciences and the National Academy of Engineering, punctured any hope that with its current and anticipated level of funding NASA will get human beings anywhere within the vicinity of the red planet. To continue on a course for Mars without a sustained increase in the budget, the report said, “is to invite failure, disillusionment, and the loss of the longstanding international perception that human spaceflight is something the United States does best.”
The new report warns against making dates with Mars we cannot keep. It endorses a human mission to the red planet, but only mildly and without setting a firm timetable. Its “pathways” approach comprises intermediate missions, such as a return to the moon or a visit to an asteroid. No intermediate mission would be embarked upon without a budgetary commitment to complete it; each step would lead to the next. Each could conclude the human exploration of space if future Congresses and presidential administrations decide the technical and budgetary challenges for a flight to Mars are too steep.
The technical and budgetary challenges are very steep. A reader contemplating them may reasonably wonder if it’s worth sending people to Mars at all.
The panel’s report, Pathways to Exploration: Rationales and Approaches to a U.S. Program of Human Space Exploration, reminds us why human travel to Mars will be a difficult proposition, several orders of magnitude more difficult than the Apollo missions, and much more expensive. Mars in its typical approach to Earth is about two hundred times farther than the moon. The shortest round-trip journey would take about nine hundred days. Mars’ gravitational pull, about one third as strong as the Earth’s, is twice that of the Moon, making the descent to its surface a lot more complicated than the graceful hovering and settling down performed by Apollo’s spindly lunar “bug.” And then astronauts would need a correspondingly more powerful fuel system to lift them off the planet for the flight home.
The report identifies two show-stopping challenges whose solutions so far are either “unknown or unattainable with current technology”: the high-radiation space environment through which the astronauts will have to travel and the design of the Mars landing craft. It also names six critical areas where “no relevant systems exist or have existed at the appropriate scale,” including a life-support system capable of functioning for years without regular supplies from Earth. Much of the equipment the astronauts will need for their survival will have to be robotically pre-positioned at the landing site, which itself presents challenges in precision landing and remote operation that are unprecedented. Some of that robotic equipment may be tasked to produce rocket fuel and other consumables from the martian atmosphere and the raw materials it finds on site—if they’re there.
The committee doesn’t put a definite price tag on the Mars mission. The final cost would depend on which pathways we chose, how quickly we wanted to get there, and what solutions we found for the technical challenges—but the ballpark figure is in the hundreds of billions. Citing polls that reflect the public’s lukewarm interest in the space program, the panel doubts that this could be raised in the current or anticipated political environment.
When we think of space, we’re inspired mostly by our deepest hopes for companionship, which would be realized by contact with an alien intelligence, and by our deepest fears about the future of humanity. Now that the Earth’s inevitable uninhabitability has become a staple of popular culture, we seem to have acquired the expectation that our species will save itself by moving to other planets. Pathways to Exploration notes the argument that the space program should emphasize colonization and the ultimate expansion of our species throughout the solar system, so that, eventually, the species may develop the capability to “outlive [the] human presence on Earth.” Christopher Nolan’s new blockbuster Interstellar depends on this premise too, with the tagline: “Mankind Was Born On Earth. It Was Never Meant To Die Here.”
The romance of outer space as refuge is amplified in Apollo 11 astronaut Buzz Aldrin’s 2013 manifesto Mission to Mars: My Vision for Space Exploration, in which he appeals for a new national Apollo-like effort to make Mars “our future second home.” The book—bearing endorsements by Neil deGrasse Tyson and Stephen Hawking—is part self-aggrandizing memoir, part crazy self-promotion, and part windy speculation about the technologies that would make travel to Mars possible. Aldrin appropriates an established concept, the orbital cycler (a spaceship that would remain in permanent orbit between two planets, ferrying settlers), and brands it the “Aldrin cycler.” He also reaches for the kind of empty rhetoric that the panel tries to avoid when it examines the space program’s motivations: he asks, “What does human spaceflight do for America? First of all, it reminds the American people that nothing is impossible if free people work together to accomplish great things.”
Aldrin calls for the landing of astronauts on the planet by 2035, a date chosen not out of any consideration of the technological hurdles that would have to be overcome or the funds that would need to be raised: rather, what is significant about 2035 is that it’s “66 years after Neil Armstrong and I flew the quarter-million miles through the blackness of space to touch down onto Tranquillity Base [in 1969]. . . . 66 years after the Wright brothers’ first flight [in 1903].” He would like to have the program announced in 2019, because it will be fifty years after the Apollo landing. Space enthusiasts cherish a kabbalistic belief in the importance of anniversaries and in the magical power of certain dates to inspire the nation or the world.
Similarly, the glow of warm feeling conjured by memories of the first moonwalk—and the supposedly forward-thinking era that produced it—motivates contemporary encomia to a potential Mars mission. Aldrin declares that “Apollo 11 symbolized the ability of the nation to conceive a truly pathbreaking idea, prioritize it, create the technology to advance the idea and then ride it to completion. Apollo is a case where we got it right. If we are to resurrect the profound feeling of participation that accompanied Apollo, we will need a Kennedy-like commitment to human exploration.” The nostalgia for the Apollo-era NASA—which at its peak was allowed to consume nearly 4 percent of the federal budget—ignores the reaction against the space program that it engendered. The “profound feeling of participation” in the space program was not as national as Aldrin recalls. The counterculture of the 1960s that became the dominant culture of the 1970s was largely distinguished by its distrust of science and technology and its indifference to the space program.
Many space enthusiasts have long since given up on the idea that NASA will ever regain its leadership in human spaceflight, and they hate talk of fiscal year budgets, intermediate paths, and long test flight programs. They just want to get to Mars, and they think they can do it independently, looking to find fresh thinking and mission-saving economies in private enterprise. Many proponents contend that any Mars trip should be one-way, for the purpose of establishing a permanent colony, eliminating the need for ascent and return vehicles. The Mars astronauts would have to live out the rest of their lives on the red planet, within a strictly controlled artificial environment.
Dying on a distant planet holds more appeal than you may think. One such project, the Netherlands-based non-profit Mars One, has drawn credulous press with its promise to land people on Mars in the next decade: Mars One has produced a drawing of its landing craft, but it hasn’t identified the vehicle that’s supposed to transport the settlers. This hasn’t stopped the company from beginning its astronaut selection process. Seventy-eight thousand people have applied for the one-way trip, and the company raised more than $300,000 in its initial crowdfunding campaign. Mars One implausibly claims it can put the first men and women on Mars for $6 billion, a fraction of what it cost to send astronauts to the moon. It says it will raise the rest of the money through the sale of television rights to the Survivor-style selection process and the flight to follow.
Elon Musk, the inventor of PayPal and the head of Tesla motors, has already put his money into a Mars mission that he says can be launched by the end of the 2020s. Other billionaires, like Dennis Tito and Richard Branson, are pursuing their own Mars projects. Aldrin himself has called for public access to space, including Mars, to be financed by lottery, with the prizes being seats on the next generation of space vehicles. But whether they’re selected by lottery or a reality TV show or, as in Musk’s case, they pay their own way ($500,000, he says), astronauts will still face serious radiation hazards, will still need to breathe and be fed, and will still have to land a multi-ton spacecraft onto a hard, cratered, rock-strewn landscape.
The urge to explore may be deeply engrained in human psychology, but space travel is a dream generated primarily by 20th-century science fiction and given form and durability, remarkably, by a single story-cycle within the genre. The panel observes, “Many space scientists, space enthusiasts, and the general public frequently cite aspects of the Star Trek franchise as their aspirational vision for the kind of future that should be pursued through human spaceflight.” (A footnote helpfully explains that Star Trek is “the well-known TV series in which humans explore on a galactic scale.”) Star Trek and Star Wars, like most contemporary science fiction set in space, depend on travel in ship-like vessels, with captains and first mates, ports of call in strange places, ship-to-ship encounters far from the sight of land, and travel times measurable in hours or days. The governing metaphor, in our thinking about outer space, is that it extends across the universe like a terrestrial ocean, dangerous but traversable, islanded with many inhabited or inhabitable planets—a notion that disregards realities about vast interplanetary distances in favor of pleasing, elevating, self-mythologizing fantasies.
The powerful, long-lived maritime analogy leads us further astray when it compares astronauts to the great European navigators who sailed to the Americas in the 15th and 16th centuries and to the colonists who followed them. In 1907, a writer of popular science, Garrett P. Serviss, was among the first to employ this analogy, in his novel about an “inter-atomic”-powered journey to Venus, A Columbus of Space. President Kennedy, noting that “this country was conquered by those who moved forward—and so will space,” invoked the Plymouth Bay Colony. In declaring his own space initiative in 1989, George H. W. Bush also recalled Columbus and then the settlers blazing the Oregon Trail.
In fact, North America may have been new to the Europeans, but human beings had been living there for thousands of years, and the land provided every necessity of life. To consider pre-Columbian America equivalent to the Moon and to the uninhabited planets is to deny the precedence of its indigenous people and the wealth of the natural world in which they lived. And while Mars enthusiasts project that someday they’ll be able to turn the raw materials of the red planet, including vast quantities of water that haven’t yet been located, into vital resources, the technology for doing so hasn’t been developed, and the means of transporting it there hasn’t been either. Mars is a desolate, radiation-seared, frigid, dim (receiving less than half the sunlight received by the Earth), probably lifeless world.
Some of recent history’s greatest thinkers, even when they don’t evoke the European settlement of the Americas, share this sloppy, unrealistic vision of human beings living off the planet. Carl Sagan, writing expansively in A Pale Blue Dot: A Vision of the Human Future in Space, declared in 1994 that, “Every surviving civilization is obliged to become spacefaring—not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive. . . . The more of us beyond the Earth, the greater the diversity of worlds we inhabit . . . the safer the human species will be.” Stephen Hawking, speaking in 2013, added, “We must continue to go into space for humanity. . . . We won’t survive another 1,000 years without escaping our fragile planet.”
But it’s not the planet Earth that’s fragile—it’s the human organism that’s extraordinarily delicate and needy, unable to survive beyond very narrow physical limits, the conditions for which exist naturally nowhere else in our solar system. To keep even a few people alive in space or on another planet requires from those left behind the expenditure of enormous resources. It’s not necessarily backwards-thinking, or anti-technology, or anti-exploration, to wonder if those resources could be better employed. The fantasy of a future new life for the species allows us to shrug off climate change and other global challenges with the thought that if we fail to make this planet livable for the billions of people who inhabit it, another is promised for us somewhere else.
A belief in life extending beyond the Day of Judgment, after this compromised, faithless, corrupt, and undeserving world has been destroyed, is another deeply engrained theme in human history. It has inspired not a few religions over the course of civilization, often distracting us from our earthly cares and griefs. Millennialist or afterlife doctrines bind us to the leaders who promote them and elicit tremendous sacrifices on their behalf. The promise of rebirth in a fresh landscape is also held out by extraterrestrial settlement. As with other kinds of transcendence, the actual mechanism of conveyance to the better world poses a daunting technical problem.
Meanwhile, outer space remains a mysterious realm of compelling questions. Their answers may not have practical benefits, but they continue to enrich and enliven the human experience, inviting us to contemplate our place in the cosmos. Beyond the search for alien life, we’d like to know what the universe is made of, especially that pesky dark matter stuff that makes up 85 percent of its mass. We want to determine the large-scale structure of the universe, its history, its future, and its mind-bending variety of natural objects, including the thousands of planets that have been discovered orbiting other stars in just the last twenty years.
Fortunately, marvelously, devices built by men and women and under the control of men and women continue to orbit the Earth and fan out across the solar system. Last week’s report that the Curiosity rover has discovered what could be microbially-produced methane reminds us that Mars is an alluring planet—whose secrets can be disclosed by robotic instruments. The New Horizons spacecraft, launched in 2006, will reach Pluto next July, achieve the first reconnaissance of the dwarf planet, and fly on to other icy Kuiper Belt Objects in the 2020s and 2030s. After traveling beyond Mars in 2012, NASA’s Juno probe returned last year to the vicinity of Earth for a gravity assist, and it’s now on its accelerated way to enter orbit around Jupiter on July 4, 2016. We live in a golden age of exploration, conducted by heroic navigators who sit at computer consoles, pursuing 21st century virtues like intellect, ingenuity and teamwork.
NASA’s effort to develop a crewed Mars mission, without the reasonable expectation of long-term funding, compromises the effort to explore the rest of the solar system, as well as research specifically designed to look for life. It makes more sense now to follow up the discoveries made by the Kepler space telescope by using advanced telescopes to search for life on the newly found planets around other stars. In our solar system, if there’s alien life, it may be found in the ocean beneath the surface of Jupiter’s moon Europa, or within the water vapor geysers erupting from Saturn’s moon Enceladus. We should send new robotic spacecraft there. The dogma about sending people to Mars will only impede the discovery of extraterrestrial life in our time.
Looking beyond our time, and still thinking boldly about going where no human-built machine has gone before, it may not be too early to start talking about launching a robotic mission to the nearest star system: the three stars located four light years away, including the bright double-star system of Alpha Centauri. You can easily see Alpha Centauri tonight, if you’re reading this in the southern hemisphere. It’s the third brightest star in the night sky, outshone only by Sirius and Canopus. One of the double stars is the same color and type as our sun. We’ve found tentative evidence of at least one planet in orbit around it. Costly and technologically intimidating, the flight would take many generations or even centuries, while history wrought its changes on our nations and our politics, our science, our culture and our mores. We would have to wait patiently for the signal of its arrival and for its first discoveries. But this project can be embarked upon in this century. Rather than indulging in fantasies about settling other planets, we would be expressing the commitment to get our act together here on Earth, our only home in a vast, inhospitable universe.