Mankind’s journey out into the black has been goaded on by many great thinkers: some, storytellers who craft amazing and fantastical worlds of science-fiction that we yearn to attain, while others are visionary scientists who challenge us with ambitious plans of how that might be achieved (while some, like Robert Heinlein, dabble in both). I’d like to change tack today and look at the latter category.
Over twenty years ago, Robert Zubrin wrote The Case for Mars, the book that inspired me as a young man (and many others, I’m sure) to grow up to study and become an engineer. It’s remained a bestseller in publication ever since, undergoing new revisions/editions every few years or so as new scientific discoveries about the red planet are revealed. More rarely, he’d add a note or two about some development in space policy or the industry that he felt worthy of note. Then, a few years ago, the “SpaceX revolution” broke onto the scene, with the advent of dramatically reduced launch prices and reusable vehicles, and it begged the question of whether Zubrin would revisit his thesis in light of these developments. The Case for Space, published in 2019, is his answer. But does it measure up to the pivotal, groundbreaking volume that started it all for so many of us?
Ex Astra, Context
The Case for Mars is aerospace engineer and entrepreneur Robert Zubrin’s detailed proposal for a rapid yet affordable effort to explore and colonize the planet Mars, a plan he refers to as “Mars Direct.” While he made a compelling case for the use of already-existing technology to save costs and to re-engineer the mission plan itself to better accommodate the founding of a permanent colony, it was the book’s accessibility that was the reason for its success. While there were math equations and chemical formulae for those who were looking for them, Zubrin made a point of keeping technical jargon to a minimum, instead relying upon logic and reason that any average laymen could understand. The genius of The Case for Mars is not that it proves its point, but that it does so by showing readers that in the end, rocket science isn’t about charts and equations — it’s about common sense.
If you haven’t read it, at this point I’ll save you some time by saying you should stop here and do so before going any further, let alone checking out Zubrin’s newest publication. You’ll be glad you did, and you will, in turn, derive the same sort of conspiratorial glee that we all get from successfully goading a friend into watching Firefly for the first time and hooking them on it.
Years later, in 1999, Zubrin wrote a follow-up, Entering Space, which began with a survey of the state of Earth-orbiting spaceflight, posited how it may be augmented and improved, retread his plans for Mars, then expanded its scope far beyond Earth’s neighbor to worlds and stars beyond the Solar system. To say that this sweeping volume of his was ambitious doesn’t do it justice — one of the final chapters postulates how, with further advances down the road, a spacefaring human race could conceivably go about helioforming — not “terraforming,” the science of altering a planet’s climate to enable it to support terrestrial life, which is already familiar to just about anyone with so much as a passing acquaintance with science-fiction, but the science behind creating brand-new suns to bring light and warmth to new worlds. Really mind-blowing stuff.
The Latest Chapter
So, given all of this, where does Zubrin’s latest offering fit within his bibliography? From the way the book is organized, it’s clear that he intended it to be “Entering Space 2.0,” with updated information, plus a decidedly more philosophical bent. Did Zubrin succeed in this aim as an author? To answer this, I’ll summarize the book and my thoughts on it on a more or less chapter-by-chapter basis.
The author’s first chapter briefly describes the stagnation of the field of spaceflight due to how “cost-plus” contract awards work in the United States. The term “briefly” is key, here, and to my mind, is the first and greatest flaw of the book. It’s split into two parts, “How We Can” and “Why We Must.” Makes sense, right? The problem is, it’s not starting in the right place. Before Entering Space got into any discussion of mass budgets to prove how affordable launches, satellites and space stations can really be, Zubrin actually spent a great deal of time chronicling what came before and why it didn’t work. He seemingly understood at the time that before he could introduce radically new ideas and upend the status quo, it served his argument well to patiently explain to readers why throwing taxpayer and investor money after “more of the same” just would not work. Most of what he related isn’t commonly known to the public, such as the fact that SpaceX’s Falcon 9 (including the Grasshopper test vehicle) was not the first rocket to successfully launch and land vertically, it was only the first to survive bureaucracy and political intrigue and persist as a commercially viable launch vehicle.
This historical background is largely absent from The Case for Space, and I would say that his arguments are weaker for it. If he’d only left some more of it in, he’d have something truly great on his hands, here.
Immediately after that, though, the book takes an…awkward turn. Recall that Zubrin’s prior non-fiction book on spaceflight well predated SpaceX’s most high-profile successes, such as the first landing of a first stage, the Falcon Heavy’s maiden flight, etc. If you go back and read his work from back in the day, you see a guarded, cautious optimism on Zubrin’s part with regards to SpaceX’s efforts. He has always voiced support and hope for the development of private and independent launch providers, but at the same time, made it clear in no unmistakable terms that the success of Mars Direct depended on “heavy lift,” the largest class of rockets, a launch vehicle that, he claimed, could only realistically be built by state-run programs. With a gigantic stainless-steel “Starship” being built on the Gulf Coast as of this writing, did Zubrin wind up eating his words?
No. He wrote a love letter instead.
Much of the early portions of The Case for Space is spent fawning over the accomplishments of SpaceX and its CEO, Elon Musk — and I say that as a fanboy of both of these men myself, yet it gets downright cringe-inducing. Whether he’s really hoping readers will forget his previous skepticism or is just really, really desperate to be “hip” and relevant to the young people who are inspired by SpaceX’s achievements, he goes out of his way to show, “Look, I totally met him at this party once, here’s a picture,” and includes more than one open call or open letter to appeal for Musk’s attention for a proposed mission architecture utilizing SpaceX’s product line. It’s unlike him, and feels out of place here.
After that, Zubrin finally discusses some areas of space-based industry and markets for launch vehicles that are poised for profound growth and expansion. Again, though, it feels a little more shallow than his treatment of the subject in Entering Space, and it doesn’t help that he continually uses a term that he seems very proud of thinking up, “fighter sats,” to describe potential defense applications for something both laymen and servicemen alike under the age of 50 would refer to as a drone.
The Moon: Once More, With Feeling
Readers may not be aware of the schism that divides the community of spaceflight advocacy into two camps, “moon first” and “Mars first.” As you may guess, Zubrin is a staunch advocate for the latter (and made a convert out of me). In spite of the scientific evidence that the moon is — surprise — an airless rock with no resources to work with aside from an unknown quantity of ice, while on Mars one can make rocket fuel from the air for free, the “moon first” faction’s enthusiasm has never faltered nor failed. So, in recent years, Zubrin has begrudgingly adapted his Mars Direct plan general architecture to say, “Okay, if we really can’t avoid going to the moon right now, what’s the best way to do it efficiently and effectively?”
To his credit as an author and a man of science, he approaches the subject with admirable impartiality and gives it no less sincere an effort than he did for Mars Direct.
Little needs to be said regarding his chapter dedicated to colonizing Mars: It’s no less ingenious and radical than its original incarnation, the only difference here is “now, with SpaceX rockets!” It is worth examination, of course, but it doesn’t change the fact that you’ll find a far more complete and articulated blueprint in The Case for Mars.
Following that, interestingly enough, he dedicates an entire chapter to asteroids — not just mining, a concept that entered the public consciousness during the early exploits of Planetary Resources, Inc, but he even goes so far as to detail at length the logistics of permanent habitation on different types of asteroids, even positing the sort of diverse cultures and the economic structures that would arise there. It’s an enjoyable read for fans of The Expanse.
It’s Chapter 6, though, that justifies the cost of the book alone for me. It’s the single most detailed and thought-out description of what colonies on and around the moons of Jupiter and Saturn would actually look like. For decades, science-fiction writers, policy advocates, and other visionaries have proclaimed that the gas giants and their satellites would be the next generation’s “Persian Gulf” — that is, the source from which Earth would derive most of its fuel for generating energy, pending a “SpaceX moment” to revive the efforts towards achieving sustained fusion reactions. Most envisioned space stations orbiting these great untapped resources, likened to isolated oil drilling platforms in the middle of the ocean, or the oft-drawn comparison of Antarctic research bases. What these analogies miss, though, is that their chosen analogues are all places of work only, where the inhabitants are only there for temporary stints and have the option to return home at some point. Zubrin, by contrast, approaches the alien world of Titan, a frigid moon of Saturn of strategic and economic value, with the assumption that its residents are permanent and wholly invested in their community’s success. I personally found myself downright enchanted by the picture he painted of everyday life for ordinary people living on Titan:
In certain ways, Titan is the most hospitable extraterrestrial world within our Solar system for human colonization. In the almost Earth-normal atmospheric pressure of Titan, you would not need a pressure suit, just a dry suit to keep out the cold. On your back, you could carry a tank of liquid oxygen, which would need no refrigeration in Titan’s environment, would weigh almost nothing, and which could supply your breathing needs for a weeklong trip outside the settlement. A small bleed valve off the tank would allow a trickle of oxygen to burn against the methane atmosphere, heating your breathing air and suit to desirable temperatures. With one-seventh Earth gravity and 4.5 times the atmospheric density of terrestrial sea level, humans on Titan would be able to strap on wings and fly like birds…Electricity could be produced in great abundance, as the 100-K heat sink available in Titan’s atmosphere would allow for easy conversion of thermal energy [to electricity]…with heat and light from large-scale nuclear fusion reactors, adding seeds and some breeding pairs of livestock from Earth, a sizable agricultural base could be created within a protected biosphere on Titan.Robert Zubrin, The Case for Space
To hear Zubrin describe it, such a foreign world sounds less like the Antarctic workplace, and more like the communities of the northernmost reaches of Scandanavia. In particular, it reminds me of a vlog by a resident of Longyearbyen, the northernmost town in the world, that has recently begun trending on YouTube. Not an unsympathetic state-run facility (important though their research might be), but an actual village filled with families and the average sort of folk you’d find populating the universe in Firefly. This is what I come for in Zubrin’s work.
The Improbable Drive
The following chapter examines in turn each of the proposed technological means of propelling a spacecraft (i.e. chemical fuel, nuclear fusion, antimatter drives, etc.) beyond our Solar system into interstellar flight. I can’t help but compare it against its counterpart chapter in Entering Space, and find it markedly less optimistic in tone. He sort of discredits his own work with his repeated disclaimer of “as an engineer…I apply physics. I don’t invent it” as he explains that these various methods will work, but will take longer than a human lifetime (at least, with today’s current understanding).
Yet, at the same time, he directly confronts the assertion made by many that, as mankind learns to harness greater sources of energy, its potential for destruction will likewise increase:
We are the children of warriors–but also of loving parents, incurable tinkerers, explorers, and reasoners. We bear the genes, instincts, and capabilities of all of these. From the warriors, we have inherited not only the instincts that threaten us but the courage to try the unknown. From the explorers, we have inherited the drive to take us to the stars; from the tinkerers, the spirit that will give us the tools to get there; and from the lovers and the reasoners, we have received that which will allow us to use our expanding powers for good instead of evil.
There is no turning back. The spirit of the tinkerers and explorers cannot be suppressed without destroying our humanity. Safety at the cost of doing so would come at too high a price.Robert Zubrin, The Case for Space
This framing prepares the reader for one of the most controversial subjects in space exploration, the terraforming of other worlds to support human life. Opposition to the idea used to be related to concerns about “playing God,” but more recently have bent more towards the claim that humans have no “right” to because we all collectively guilty about global warming.
It is here that he rather bravely pauses to consider the subject of climate change with admirable neutrality. As a former skeptic myself, I can honestly say that Zubrin made a “convert” out of me, if you’ll pardon the metaphor, with the strongest case in favor of anthropogenic global warming I’ve ever heard. Not by arguing, shouting, or shaming, but by calmly presenting all sides and data for the issue as science instead of as religion which climate activists often do. I don’t want to do him or you a disservice by paraphrasing a rare voice of reason in an age that lacks it more with each passing day, so I’ll say this much: He starts by presenting what’s right and what’s wrong with both sides, and admits where there are flaws in the arguments — then he uses completely different, far more compelling data than average temperature readings to suggest that global warming is occurring faster than would be expected from the natural trends that have taken place in recent centuries, correlating with the advent of fossil fuels. He also shows real evidence that this does have an adverse effect on the biosphere — it’s just not what we’re often told that it is, and it’s less known because it is not the kind of thing that makes for dramatic television, viral posts or sound bytes that could make a politician or a corporation look good.
Then, related to that, rather than excoriate the reader, or preach doom, gloom and panic, he actually proposes a realistic, science-base solution (as opposed to a punishment for all mankind) that both sides should be able to get behind in a sane, rational world. One that solves a real problem with the environment in a realistic, proven way that’s inexpensive and benefits flora, fauna, and human beings alike (and is even a legit boon to local economies). Not bad for an aside in a book about spaceflight.
He ends the chapter and Part One of The Case for Space with another topic that he did more justice in Entering Space, the helioforming I mentioned earlier. Here, it gets barely a passing mention, maybe a page and a half of discussion. In Entering Space, it got downright wild with the possibilities, going so far as to work out the actual math of the energy and chemical/physical processes that would be involved with stoking the fires of a “dead” star to bring new warmth to the worlds around it. Awesome stuff; it’s disappointing to not see it get that same treatment again.
“We Choose to Go to the Moon, Because…”
Zubrin essentially chose to write two books, one explaining the how of space, and one explaining the why. On paper, this bifurcated approach sounds like a good idea. And it almost works, too — except that in practice, he failed to completely separate the two, and was forced to make a few ethical and moral justifications along the way. This is something you just can’t avoid when it comes to space, and is not to be blamed on Zubrin.
Why? Because sailing the black ocean isn’t just a journey of scientific exploration, it’s more than expanding a frontier, it’s a bold and provocative statement on the nature and character of the human race. Advocating for the colonization of other worlds is an unequivocal declaration of belief that men and women have inherent worth, are noble, and worthy of not just surviving and continuing to live, but doing so without restraint and flourishing. These things used to be accepted as universal truths, and therefore were never discussed in books on spaceflight in decades past. Sure, the likes of Robert Heinlein and Isaac Asimov used the black velvet backdrop of space as they explored different ideas of political philosophy, but it was more or less taken for granted that people would seek answers out there, let alone be permitted to by society.
Which brings me to another profound problem with The Case for Space as a whole. The entire second half is dedicated to Zubrin’s arguments described in the chapter titles:
- For the Knowledge
- For the Challenge
- For Our Survival
- For Our Freedom
- For the Future
It’s assumed that the reader agrees that there’s inherent value in the goals these chapters describe: Expanding human understanding, enriching our stagnant culture, ensuring the survival of the human race, and preserving freedom and liberty. The problem is that can no longer be assumed, especially with rapidly growing numbers of young people declaring that, for example, freedom of speech is “dangerous,” and that the best possible moral outcome for the human race would be extinction so as to avoid “damaging” the Earth any further. Zubrin seems to have missed the boat here, and may not be aware that a large part of the general public no longer has this shared basic foundation to build upon or “holds these truths to be self-evident.”
Answering such nihilism decisively can be done, but it is beyond the scope of a book about rockets to the stars (and becomes less technical and science-related the more you get into the weeds), and at the very least requires that it be a book in and of itself. It can’t be properly handled as an afterword in a popular engineering book.
If this seemed a little “all over the place,” it’s because that’s my final, greatest criticism of The Case for Space. While Entering Space was a seamless narrative that tells a story of mankind progressing from dipping its toes in Low-Earth Orbit to eventually creating new stars, this new version feels disjointed and less cohesive. The Case for Space is more of a collection of different, separate ideas, some shining more brilliantly than others. Had I been Zubrin’s editor or publisher, I would have strongly urged him to consider simply inserting some of these truly wonderful new concepts into his earlier work and publish it as a new revised edition of Entering Space.
So, do I recommend reading it at the end of the day? Yes — but only if you’ve already read Zubrin’s other works. It simply doesn’t work as an “introduction” to his nonfiction books, much less as a primer on spaceflight itself to an uninformed laymen. For that, I still recommend Zubrin’s The Case for Mars without hesitation, regardless of whether you’re a card-carrying rocket scientist, or can’t pass a chemistry class to save your life (I happen to fall in both categories).