Spacefarers: How Humans Will Settle the Moon, Mars, and Beyond

by Christopher Wanjek

A Telegraph Best Book of the Year

A wry and compelling take on the who, how, and why of near-future colonies in space. From bone-whittling microgravity to eye-popping profits, the risks and rewards of space settlement have never been so close at hand.

More than fifty years after the Apollo 11 moon landing, why is there so little human presence in space? Will we ever reach Mars? What will it take to become a multiplanet species, colonizing the solar system and traveling to other stars?

Spacefarers meets these questions head on. While many books have speculated on the possibility of living beyond the Earth, few have delved into the practical challenges or plausible motives for leaving the safe confines of our home planet. Christopher Wanjek argues that there is little doubt we will be returning to the Moon and exploring Mars in the coming decades, given the potential scientific and commercial bonanza. Private industry is already taking a leading role and earning profits from human space activity. This can be, Wanjek suggests, a sustainable venture and a natural extension of earthbound science, business, and leisure. He envisions hotels in low-earth orbit and mining, tourism, and science on the Moon. He also proposes the slow, steady development of science bases on Mars, to be followed by settlements if Martian gravity will permit reproduction and healthy child development.

An appetite for wonder will take us far, but if we really want to settle new worlds, we’ll need the earnest plans of engineers, scientists, and entrepreneurs. Wanjek introduces us to those planners, who are striving right now to make life in space a reality.

Genres: Science, Nonfiction, Space, Audiobook, Technology, Futurism, Physics

400 pages, Hardcover

Published April 14, 2020

Reviews

[Jim · Rating 5 out of 5]

Wanjek looks at space colonization through a very practical, economic lens which includes actual colonization. He defines the last with couples having children 'naturally'; very persuasive & practical arguments. He looks at energy requirements & the current technologies for producing it. This is a rather broad view that brings into focus what we need to explore & aim for to spread throughout space. He also points out possible services & goods that these outposts can provide to insure economic viability since without some ROI (preferably profit, of course) space remains the domain of countries & a slave to their current administration. Just how badly this has hurt NASA's various projects is both directly & indirectly addressed.

Like me, he's a fan of NASA's & doesn't forgive them for the space shuttle & ISS debacles. Yes, both were because they spent a huge portion of the budget without advancing our knowledge nearly as much as many shelved projects. I especially liked the way he pointed out how obvious it was that microgravity is bad (1% bone loss per month!) & that it's practically criminal that no experiments have been done with lesser gravity situations such as those equal to Mars or Luna. Just how much is 'enough' gravity? We still don't know & we should. We haven't even tested any ways of creating it at scale, so the long trip to Mars is not feasible at this time. The astronauts would arrive in such bad shape that it would threaten the mission.

He starts in the local solar system & works his way out as the book progresses. Of course, the opportunities for colonization & economic rewards vary a lot. They become scarcer, but still remain even in the outer reaches of the solar system. Many of the moons are mentioned, albeit briefly, but that fit well within the confines of the book & left me wanting to read more on some subjects. He also provides his own guesses as to what the future holds.

Table of Contents
Introduction: Pre-Launch
1.   Living on Earth
2.  Checkup before Countdown
3.  Living in Orbit
4.  Living on the Moon
5.  Living on Asteroids
6.  Living on Mars
7.  Living in the Inner and Outer Solar System and Beyond
Epilogue: Welcome Home

Well narrated, entertaining, & very interesting. Highly recommended.

Update 18Aug2021: I watched Disney's Man in Space (1955). This was one of their Sunday shows which came on at 7pm on channel 11 when I was a kid & was a time the whole family watched TV together. The show aired 2 years before Sputnik, so I was surprised by how well the basics were explained including the first quarter being a history of rockets. The explanations were enhanced by quirky cartoons, too. Werner Von Braun & other notable rocket pioneers were not only mentioned, but spoke at some length on their parts of the space program. Von Braun describes a 4 stage rocket that boosted a space shuttle nose cone carrying 1o people into orbit which then glided back down. The 1300 degree hull temp they projected was less than half that of the space shuttle (3000F) but I was still impressed by how much they got right. It's well worth watching.

[Terri · Rating 5 out of 5]

Space is infinite. Humans and robots will build space hotels and explore and settle the moon and Mars. We will than go beyond Mars. Astronomy writer, Christopher Wanjek, writes a fascinating and balanced book about human space exploration, policy and commercialization. I especially appreciated how realistic he was about our future in timing the space ventures and the financial plus scientific gains that could be attained. Equally interesting was the Mars Direct plan which was explained to the reader in very clear terms. I also learned about the practical challenges facing us such as gravity issues on the human body and fuel problems. The two reasons to explore seem to be military race (China has two space stations already which they don't publicize)) and business such as tourism and mining. Five stars.

[CatReader · Rating 4 out of 5]

Christopher Wanjek is a science journalist; his 2020 book Spacefarers is an imaginative exploration on how humans might explore, utilize, and ultimately settle in areas of our solar system beyond Earth. This was an interesting, engaging listen, though it remains to be seen how much of Wanjek's starry-eyed (pun intended) aspirations may ultimately come into fruition.

Further reading: other books on solar system exploration I'd recommend
The Sirens of Mars: Searching for Life on Another World by Sarah Stewart Johnson
Chasing New Horizons: Inside the Epic First Mission to Pluto by Alan Stern
The Interstellar Age: Inside the Forty-Year Voyager Mission by Jim Bell

My statistics:
Book 276 for 2025
Book 2202 cumulatively

[Gendou · Rating 4 out of 5]

This is a decent book on one of my favorite topics. It runs through the reasons for, challenges with, and paths towards going into space beyond this one rock we call home.

The author presents his informed, balanced views in a relatable way. I feel like it could have gone into more detail on some of the science stuff, like off-earth ecosystems and health under differnet gravity. He actually put a lot of effort into these. He sticks closely to what's been experimentally proven. But these are big topics and I'm hungry for more, including the speculative and theoretical. He does go into the most depth on the economic questions.

[Kay · Rating 5 out of 5]

Very interesting and entertaining read. Highly informative, if a bit opinionated (though, as a writer for NASA, he is definitely entitled to those opinions!).

[Paul Spence · Rating 5 out of 5]

Spacefarers considers, as the subtitle has it, How Humans Will Settle the Moon, Mars, and Beyond -- though the 'how' is fairly flexible here: in some cases, necessary technology is already available (though often still cost-prohibitive); in others it remains largely theoretical (though plausible, in some form) for now -- and then there are the issues which seem likely to always be an issue: (lack of) gravitation, cosmic radiation, and the sheer length of time it takes to get almost anywhere in space (the problem not so much one of speed -- that can be achieved -- but rather acceleration (and deceleration), which the human body can only tolerate so much of). The technical difficulty of shooting something into space, or at least to a (relatively) nearby specific place, like Mars, is almost the least of the problems (though, for example, simply landing something on Mars -- that last little step -- without breaking it has proven to be very hard); human requirements are such that travelling and living in space with a reasonable chance of survival really complicates matters. As Wanjek notes, most present-day 'space' travel is pretty low orbit, still well within the earth's protective shell of the magnetosphere. Beyond that, the challenges quickly grow quite daunting.

Wanjek is no space-romantic. He's intrigued by space travel, and also sees it as inevitable, but emphasises that, especially as far as lifestyle goes, it will be a long, long, long time, if ever, before anywhere out there is even just anywhere near as good as earth, much less an improvement on terrestrial conditions. For him: "Human space exploration is not a plan B for Earth", arguing that even if the worst were to happen -- nuclear Armageddon, for example -- those on earth will still have it better than anywhere in outer space for the foreseeable (and long beyond) future. Indeed, much of the fun of Spacefarers is in his detailed overview of just how bad conditions are out there -- in any vehicle transporting humans, and then everywhere they might set(tle) down, from the moon and Mars to asteroids, comets, and more distant planets and their moons.

Wanjek begins with a look at 'Living on Earth', and experiences in the most extreme conditions available here -- and how humans can handle these: high altitude or Antarctic cold and isolation, for example, or months in a submarine. Terrestrial efforts to practice for space travel and self-sufficient living away from earth -- NASA's Human Exploration Research Analog or Biosphere 2, for example -- give some sense of some the difficulties spacefarers face -- but, as Wanjek shows, there's a whole lot more to deal with .. out there.

Wanjek progressively makes his way up from 'Living in Orbit' -- the close-to-the-earth travel that has dominated human space travel to date -- before moving progressively on to living and working on the moon, asteroids, Mars, and then beyond. He concludes each of these sections with his predictions, as to what is likely and how soon -- taking into account not only what is and will be (technically) possible but also whether it will be worthwhile: sure, valuable mineral wealth, for example, can be mined on extraterrestrial bodies near and far, but you really need to get a lot of bang for your mining-buck investment to bother with it. His predictions range from what he sees as likely, soon -- "the first space hotels open by 2025" (explaining also how very rudimentary these will be, as far as comfort goes -- but also why they'll still appeal to (some of) the ultra-well-heeled) -- to the more distant ("science and technology have advanced by the end of the twenty-second century to allow for human scientific exploration throughout the Solar System, yet there remains no need for commercial activity or residency beyond Uranus").

Each more distant layer -- low terrestrial orbit, moon, Mars, and beyond -- brings additional complications, and Wanjek does a good job of presenting these, and discussing possible work-arounds. Gravity is a constant problem: the human body doesn't seem to fare well in low or no gravity over the long term, and he points out that a critical issue will be at what level of gravity humans can procreate -- will Mars' 0.38G be sufficient for full gestation, for example ? Radiation -- "nearly manageable solar radiation and the more menacing cosmic radiation" -- are significant issues in getting from any point A to B, as well as on those bodies without an atmosphere. And then there are the difficult local conditions: among the issues on the moon is the omnipresent lunar dust ("razor-sharp and abrasive like asbestos"), while the minuscule atmospheric pressure on the surface of Mars (6 millibars, compared to 1,000 on earth at sea level) means humans can only work 'outside' in unwieldy pressurised spacesuits. Never mind places like Jupiter -- uncolonizable, Wanjek points out, because: "There's no surface" -- or Uranus, where the planet's extreme tilt (97 degrees, meaning its: "poles essentially face the sun") means the poles get: "forty-two years of perpetual (dim) sunlight followed by forty-two years of darkness during Uranus's eighty-four year journey around the Sun". Venus, meanwhile, is: "both the worst and best in the Solar System to establish an off-Earth colony", with its reasonable gravity (0.9G) but consistently extreme temperature (hotter than Mercury ...).

Wanjek considers the trade-offs and risks -- and how much is still unknown about these. Technological advances continue apace, but fundamental issues remain: earth's strong gravity will long remain an issue, requiring a great deal of energy (in the form of heavy fuel) to lift anything into space, and cosmic radiation is a hard-to-shield against universal on any space voyage (for now best protected against by what amount to half-measures). He points out life anywhere else in space will not conform to the cinematic-idyllic, most of the time: in many places, it's only sensible to shelter underground, or in heavily protected structures, with windows a luxury: those impressive vistas won't be what you wake up to every morning. Space will always be at a premium, both on the way to anywhere and then anywhere you settle down.

Spacefarers usefully gives a good overview of what has been achieved and what is in the works -- complete with missteps along the way -- along with the more speculative, making for a realistically grounded overview. A great deal can be accomplished and learned without a human presence, as many space probes have demonstrated, but Wanjek also understands the human yearning to explore in person, and to go where no one has gone before; he also understands the appeal (and value, in that it is revenue-generating) of space tourism.

It makes for a good, quite thorough tour of all the possibilities as well as the issues and dangers, realistic and not too simply wide-eyed, and written with a helpful dash of humour. Certainly of interest to anyone curious about space travel and the (possible) human colonisation of outer space.

[Pete · Rating 4 out of 5]

Spacefarers: How Humans Will Settle the Moon, Mars, and Beyond (2020) by Christopher Wanjek is an excellent book about space travel. The book carefully goes through just how hard space travel and living in space will be. But despite the difficulty Wanjek writes with optimism. Wanjek writes on health and science and has worked at NASA.

The book starts by looking at just what earth provides. We take air, food, water, gravity and radiation shielding for granted on earth. In space all these things are hard. Wanjek also looks at the justifications for space exploration. In addition he argues how Antarctica is an easier, but still very difficult place to live on earth and what we can learn from that.

The second chapter more closely describes the health issues that will be encountered in space. Wanjek writes really interestingly about gravity and how the lack of it causes problems. He also outlines how spinning spacecraft could generate a force like gravity but curiously how little exploration has been done on this. Wanjek points out that we don’t know if some fraction of gravity helps a lot.

The next chapter is on living in space and considers travel and living in giant space stations. This sort of development was written about by Gerard K O’Neil in his book ‘The High Frontier’ . Wanjek writes about the International Space Station (ISS) and what was learned from that. He points out the staggering cost and that the science results from the ISS were disappointing.

Wanjek then writes about living on the moon. He again argues how hard it would be but how it is very possible. The Lunar regolith is useful but the dust is terrible. It cuts. It’s like Asbestos if it gets breathed in. There is chapter that considers living on Asteroids and what resources can be obtained from them. Again, it’s hard but it is plausible and could potentially be profitable.

The longest chapter in the book examines how Mars could be explored and settled and also why this should be done. Wanjek carefully goes through why Mars would be worth exploring and how difficult it would be. Protection from radiation and growing food on Mars would be really hard. Also the time for travelling of several months at best becomes a major issue. Possibilities for terraforming Mars are also examined. Wanjek also references Robert Rubin’s books on Mars exploration.

There is then a chapter on living on planets and other places that haven’t been considered as much. The possibility of living on Venus in balloon cities is amazing. It’s remarkable that floating cities could be plausibly be built. Wanjek also discusses how it may be possible to terraform Venus. The outer solar system, living and exploring moons of Saturn and Jupiter is also described. It’s fascinating to ponder how this could be done with different types of probes for the different moons. Living on the Oort Cloud and near Uranus and Pluto are also considered.

Finally Wanjek summarises the book and puts forward some timelines for space exploration. Despite carefully writing about how hard space exploration is Wanjek finishes with hope.

The book does mention probes and robots regularly but there could be more on this. There is limited discussion of interstellar travel but this is where unmanned ships with frozen DNA could potentially be much easier. Von Neumann probe type things.

Spacefarers is a really good book. Wanjek does a great job of carefully writing about how hard space travel is but does so without cynicism. The book is very readable and informative. Anyone interested in space travel should enjoy the book. It changed my thinking about space exploration by describing just how hard the challenges are but that they could be overcome.

[Art Enyedy · Rating 3 out of 5]

The complete title for this book is Spacefarers: How Humans Will Settle the Moon, Mars and Beyond. This book, published in 2020, it is an up to date synopsis of mankind's next ventures into space. The opening chapters are explain some history (it's been 50 years since anyone last walked on the moon!) and describes the challenges of visiting space. Basically, it is both dangerous and expensive to boost any payload out of our deep gravity well, and once you get to space, humans are vulnerable to weightlessness and radiation. Living in space is hard. Providing food, water, air, pressure, shielding - all of these things are difficult. There needs to be a good reason to travel to space.

The presence of water on the moon makes a return to the lunar surface more attractive. By now, most readers will have already heard of the discovery of ancient ice in the deep craters at the moon's poles. The axis of the moon tilts only 1.5% (as opposed to the 23% tilt of the Earth), so sunlight never reaches the depths of the polar craters, which means that literally tons of water could be extracted. I did not realize how hard it would be to extract this frozen ice, it exists at temperatures so cold that chiseling the ice out would require a feat of engineering. I did not know that radiation danger is so great on the airless surface that a permanent base would require a layer of regolith 15 feet(!) thick to protect the shelter from cosmic rays. The moon rotates slowly, it takes a month to complete one rotation, which means its days and nights are two weeks long.
Temperatures soar during the two week day, and then plunge to frigid lows during the night. I had not known that the Apollo missions were carefully timed to be on the lunar surface during the transition from night to day, the astronauts were only there at the dawn hours. If they had stayed longer, they would have roasted. I was also unaware of just how deadly the lunar dust is. It is statically charged, so it clings to everything, and because there is never any erosion due to wind or rain, the edges of the dust are sharp and corrosive.

So why go to the moon? The biggest lure is the molecules of He3 that have been embedded in the lunar surface by the sun over billions of years. He3 is ideal for powering fusion reactors. Unfortunately, we are still a decade away from being a decade away of having commercial fusion power. The second best incentive for returning to the moon is to extract water and materials. Once infrastructure is in place, it would be cheaper to send materials from the low-gravity lunar surface to Earth orbit, than it would be to lift those same materials up from the deep gravity well of Earth. The key, of course, is "once the infrastructure is in place". I wish that Wanjek had spent a lot more time discussing how mining robots would function and then the lunar base would transport the extracted resources to Low Earth Orbit.

The asteroids are the most intriguing. Wanjek says that there is enough material in the asteroid belt to support 10 trillion humans. I don't know that humanity could or should expand to such numbers, but that does indicate how much raw material is available to a future space faring civilization. There are three types of asteroids: C-type (Carbonaceous or primarily carbon based) which make up 75% of the total rocks, S-type (Silicaceous or primarily silicon based) which are another 20%, and remainder are M-type (Metal). Near Earth Asteroid UW158 is about 300 meters long but is estimated to contain billions of dollars worth of platinum (How do they know the composition of an asteroid we have never visited?). NASA had a plan, called the Asteroid Redirect Mission to visit an asteroid and retrieve a boulder for study, until the Trump White House killed it. I wish Wanjek had talked more about how to mine asteroids, and how to change their orbits. It seems to me that asteroids are the way to go - platinum, gold, titanium, cobalt and rare earth in incredible abundance is too juicy a target to pass up. Maybe use all those asteroid resources to build vast L-5 style colonies to house recreated ecosystems - could we build a forest, jungle or alpine wilderness in space, and stock it with endangered species, while humans lived beside them?

The case for Mars didn't sound too convincing to me - unless the goal is scientific research and the quest for life. Mars is so far away that astronauts would need to travel in a rotating ship to create artificial gravity, and if we can build rotating ships, we can colonize near space by building habitats with materials from the Moon and asteroids. Terraforming Mars by bombarding it with comets is theoretically possible, but currently way beyond our present technology.

The end of the book discusses the more exotic destinations: Mercury, the clouds of Venus, the moons of the gas giants, and colonizing comets. Given the huge amount of resources available in the asteroids, it would seem unnecessary for humans to travel to such challenging and distant locations, except perhaps on missions of science. There is no talk about destinations beyond our solar system. Did you know that the Oort Cloud doesn't begin until 10,000 AU? I had no idea it was so remote. The Oort Cloud extends from 0.8 to 3 light years from the sun. If we ever run out of asteroids to mine, we can send self-replicating robots out to those empty depths to tow home more rare materials, in some distant century hence...

Wanjek is an optimistic guy. At the end of the chapters, he predicts dates when mankind will achieve certain milestones. The first space hotels will open in 2025 (remember, this book was published in 2020, so that is very optimistic!). The first orbital ring station becomes operational early in the 22nd century. Humans back on the lunar surface in the 2020s, permanent lunar presence starting in the 2030s. Robot mining of asteroids commences in the 2030s. He predicts a Chinese / US race to Mars in the 2040s, with permanent presence in the 2050s. Humans will have solar sails and ion rockets and use them to visit the clouds of Venus and moons of Jupiter by the end of the 21st century. In the beginning of the book, Wanjek details the fifty years of frustration and inaction since the Apollo mission, so it is a surprise to see such hopeful predictions. People alive today could live to see these adventures come true. If only it were so.

[MJ Tian · Rating 5 out of 5]

2nd Audiobook - again, still faced the same kinds of difficulties that I experienced with "When the heavens went on sale" about the retention.

On the content, extremely clear and concise summary of what it will take for humans to become a spacefaring species.

I really appreciate how this book jumped right into the history of tests that we have done about the impacts of space on the human body ... and it is not a pretty picture. I had initially thought that the astronomical (no pun intended) costs of sending humans into space and the general lack of a compelling economical justification might be reasons why intergalactic travel might never become possible. However, it might seem that the negative health impacts might actually be the real culprit. To put simply - 1) our bodies have evolved to thrive in 1G and living in anything but that could cause irreversible health complications, 2) there are many features of Earth (e.g., magnetic fields, water) that enables life on Earth that is simply not present in Space.

Space aside, this book did spark me to ponder ... how much of what we think we know about space are actually known with certainty, and how much are just extrapolations or "statistically significant" guesses. Maybe I should have studied astrophysics...

[Jacob Hay · Rating 4 out of 5]

Excellent analysis of the future of human space flight. My only gripe is that of any futurism book, the predictions are too early, even in this very conservative estimate.

[Conan McCann · Rating 4 out of 5]

Good summary of the progress on permanent space settlements by humans. The author is way more sceptical of the prospects for permanent cities on Mars than Elon Musk. Author cites issues of money (who pays for it, and why?), low or zero gravity (if humans turn into boneless blobs of withered muscle on Mars or the moon, then cities there with families and kids are a non-starter), and ionizing radiation (better have a lot of shielding!). But still predicts we will get there eventually, so he's optimistic in the (very) long term. If you are interested in space and space travel, this is a gripping book, but if you're fine with living on Earth forever, then you'll find this book boring. Also, has some annoying typos.

[Kiril Valchev · Rating 5 out of 5]

„Human space exploration is not a plan B for Earth. Rather, our activities in space make living on Earth better. ….Space technology and exploration is far from futuristic escapism. It is the here and now.“

„Spacefarers“ е сред най-добрите заглавия, излезли през последните години, посветени на усвояването на космоса и колонизирането на Слънчевата система. На Кристофър Уанджек не му липсва оптимизъм, относно бъдещето на вида ни сред планетите, луните и астероидите около родната звезда, но подхожда с резервираност, обсъждайки реализирането му (средствата, причините и сроковете). След като ни среща с „най-космическоподобните“ места на Земята – Антарктида, ядрените подводници и високите пустинни плата, Уанджек отправя взор към бъдещите хабитати в ниска околоземна орбита, изследователските станции на Луната, мините в астероидния пояс, колониите на Марс, евентуалното ни присъствие сред облаците на Венера, около терминатора на Меркурий, върху луните на газовите и ледените гиганти и, в много по-далечна перспектива, отвъд Слънчевата с-ма. Всеки етап е съпътстван от обстойни описания на изключителните предизвикателсва, които Homo sapiens ще срещне по пътя си към Homo futuris.

[Kevin Orrman-Rossiter · Rating 4 out of 5]

this review was first posted here: https://almostlucidthoughts.tumblr.co...
It is more than fifty years since NASA placed men, twelve in total, ‘for all mankind’ on the Moon. Since the heady days of the Apollo missions humans have not set foot on another celestial body. We have sent robotic missions to many parts of the solar system, including numerous rovers to Mars. Yes we have a presence on the International Space Station, orbiting some 400 kilometres above the earth’s surface. But astronauts orbiting in microgravity in a near earth orbit is a far cry from habitations on the Moon or Mars or the asteroids. Why is this? More particularly what will it take to become a spacefaring society? In Spacefarers, science writer, Christopher Wanjek tackles the first question, while answering the second question, in a clear, pragmatic and interesting style.

Wanjek starts by challenging us to answer the question 'What’s the reason for human space exploration celestial bodies?’ the trite response that exploration is part of the human spirit will not suffice. Probing this critical question provides a sound start to exploring what next. the past was driven by national pride and the threat of war - leading to landings but no settlement. In the future, he argues, 'a war may get us to Moon or Mars; economic sustainability will keep us there.’ This may sound trite but Wanjek explores it in detail and returns to these points in each successive chapter on living on the Moon, asteroids, Mars and the inner and outer solar system and beyond. Asking and answering this critical question also leads him to see what he sees as the failure of the ISS.

Wanjek has his preferences and ideas clear from the start, he does not find much merit in the ISS, if its intention, as is often stated, is to prepare us for habitation on any celestial bodies. Microgravity he states clearly is not an environment for humans at all. Living in orbit yes, but under artificial gravity, not the microgravity of the ISS. Wanjek is all for space exploration, Spacefarers, as he unambiguously states, is about space settlements - which he clearly defines as habitats in which humans can successfully have babies and rear them to being functional adults. Wanjek does explore, very adequately, the benefits that commercial 'space tourism’ will provide as an interim and possibly ongoing part of space exploration. But he maintains it will always be a modest input into the commercial viability of settlements. The viability will be from mining and/or the provision, directly or indirectly of energy to either earth or the off-Earth settlements. Without this there will be no settlements, there may be scientific stations - similar to what is currently on Antarctica - but no settlements.

He questions the ludicrous health-focussed efforts on the ISS which make no attempts to understand the health effects of low gravity, the 0.16G of the Moon or 0.38G of Mars, in comparison to the (almost) zero gravity on the ISS, on the human body. There have been no attempts to test artificial gravity to understand whether we could survive without the 1.0G of earth - microgravity provides no indication of that - other than it is detrimental to humans.

Gravity is a key for human settlement, next is understanding the impacts of temperature, pressure and radiation on the ability of humans to have babies and rear children. The book is very strong on assessing these factors - something that the more fanciful 'space is our destiny’ type of writing under-play or glibly misrepresent. There are a number of specific books that provide well-researched and worthwhile reading that support aspects of human settlement on the Moon and Mars - I recommend Harrison Schmitt’s Return to the Moon, Robert Zubrin’s The case for Mars, and Buzz Aldrin’s Mission to Mars, particularly. Spacefarers is an imaginatively written, well-researched and very accessible broad-brush perspective on the next steps in human space exploration with the intent to settle.

[Joseph Hirsch · Rating 5 out of 5]

It is a tricky balancing act, to write something that is accessible to the layman and yet rich enough in information that the more knowledgeable don't feel shortchanged. It's a tightrope that author Christopher Wanjek walks quite well (and in zero G, no less) in "Spacefarers." He knows his science thoroughly, but he knows his science fiction, too, and also how to keep the reader engaged.

Spacefarers is a well-organized, thoroughly engrossing look at the human presence in space, in the past, present, and the future. It starts by describing efforts to mimic life on another planets by conducting experiments in harsh-but-earthbound environments (Antarctica, etc.), then moves on to the forays of the Super Powers who were spurred on toward the stars less by their imaginations than by the hard exigencies of the Cold War. From there the book moves on to cutting edge efforts by mostly private firms and maverick billionaires to beat the state-sponsored Leviathans to the farthest reaches of the stars. What's most impressive about the book (and it's all impressive) is that even when it becomes theoretical, it feels grounded in the thoroughly plausible. The author has all the pluck and can-do of a Golden Age SF writer, but he also understands those with mundane concerns who feel that perhaps we should worry about the Earth and its problems before looking upward. It's a tribute to Dr. Wanjek's skill as a writer and his intelligence as a scientist that he can make the argument that our melioristic instincts can best be satiated by searching out the riches of other planets, comets, and moons. This isn't a "Planet B" argument about what we should do after we trigger runaway greenhouse gasses on Earth and need to find another world to wreck, but rather a long-range plan to satisfy the prerogatives of everyone on Earth, from the richest to the poorest of us. Whether it can work or not, I don't know, but "Spacefarers" makes a strong, fascinating, and heck, fun case for continued space exploration and settlement. Highest recommendation, with plenty of photos and cool conceptual art included.

[Matt Conger · Rating 5 out of 5]

Easily one of my favorite books of 2021. The author talks about the logistics of what colonization in various places outside of Earth would entail. He combines economic, scientific, ethical, and geopolitical concerns. And he organizes the book with the most practical stuff first (space tourism) and the most fanciful stuff at the end (commandeering a comet).

His writing style is also amusing. He talks about a discovery made by the Italian Space Agency and, in a footnote, noted that this was a double-discovery for most people: not only the space-related discovery, but also the fact that Italy had a space program.

The biggest thing I learned is that the US squandered a chance for leadership in terms of actual spacefaring (that is, colonizing space).

Most of the resources given to NASA after the Apollo missions were focused on incremental improvements to terrestrial (Earthbound) science. And making it worse is that NASA doesn't have the autonomy to create its own direction. Not only do US presidential administration micromanage NASA far more than other countries' space programs, but those administrations rarely want to continue the priorities of their predecessors. Adding insult to injury is that there is a horribly inefficient supply chain for space-related stuff, as politicians have individually demanded that their districts get awarded certain contracts. One of the easiest-to-understand predictions is therefore that China will beat the US to Mars and thus set off another space race.

Another reason why I liked this book is that my son will, like nearly all children, inevitably get obsessed with space at some point. We live near NASA's JPL and he'll most likely be at that precocious, impressionable age of 10 when humans may set foot on Mars. So I can totally see myself handing him my heavily-annotated copy of this book and him loving it.

[Barb · Rating 4 out of 5]

Guess this is my month for reading science books about space exploration and colonization. Not long ago, I listened to Stephen Hawking's Brief Answers to the Big Questions and Carl Sagan's Pale Blue Dot. While the covers of those two were much more appealing than this cartoon-ish cover, the content of the book (which is what really matters) was almost as good.

The author starts with a brief look at what we, as humans, have accomplished to date regarding space travel - and it isn't much. It's been 50 years since anyone walked on the moon! He then moves on to the somewhat practical issues (like space tourism), the dream of actual colonization of the moon, Mars and other celestial bodies, and ends with the highly fanciful (like harnessing and commandeering a comet).

At each stage, he discusses the practical, financial, scientific, ethical and political concerns, raising thought-provoking questions along the way. For example: If the absence of gravity isn't conquered, all talk of colonization in space are moot, if only because human procreation won't be possible.

I hope to persuade Hubby and Son to listen to (or read) this book. They are both much more familiar with our current space "situation" than I am, and I'd love to hear their thoughts on the author's thoughts.

[Thomas · Rating 4 out of 5]

Wanjek, Christopher. Spacefarers: How Humans Will Settle the Moon, Mars, and Beyond. Harvard UP, 2020.
Science writer Christopher Wanjek is nowhere near as optimistic about near-off-planet space colonies as his subtitle makes it sound. He is cold-eyed about the politics and economics of space exploration. He gives Johnson more credit for the moon landing than Kennedy and argues that if Nixon had won the 1964 election, the moon landing would not have happened. The space shuttle program was, to say the least, inefficient. Near future efforts in space will probably be motivated by an attempt to make a profit, through space tourism perhaps, or by political competition with China. Settlements on the moon will be more like settlements on Antarctica than anything more romantic. Permanent settlement will depend on whether or not low-gravity interferes with human gestation. Mars is the best hope for permanent residency, but he explains why farming on Mars is not easy. Perchlorates in the Martian regolith, for example, would have made any potatoes Mark Watney grew there poisonous. Wanjek is ultimately hopeful about human futures in space, but he does not underestimate the challenges or the time it will take to get there.

[Liquidlasagna · Rating 2 out of 5]

A strange book, lots of accurate details, but he seems wildly overly optimistic, with that slightly off-putting free-enterprise "we can do it", and "there's a slight chance it could be a reeeeeeal Gold Rush"

but the real disturbing part if when his glowing reviews come from the flaky hard-skeptic crowd, and he's written some questionable books on "bad medicine" with that creepy skeptoid vibe that rings as weird as Scientology!

[skeptics are fanatics, and sadly they hijacked the word to say 'my opinion' is fact, and 'your opinions' are worthless. Be skeptical of skeptics!]

It's got that slightly creepy Newt Gingrich and Jerry Pournelle free enterprise space futurism to it, but i think i did say optimistic.....

..........

I like how he gives a fair dose of the history and technology

but it's utter dog-crap when he says idiotic stuff like

"the first space hotels open by 2025"

gag me with a spoon on mars please!

.......

and in 15 months, time to buy some of that hot space hotel stock, woo!

[Stuart · Rating 4 out of 5]

Our beloved 20th Century Science Fiction did us a great disservice as it omitted all of the hard problems that remain for humans to settle other than on the earth. So book looks at all the aspects of humanity's future in space.

One important factor that it beings up is that we don't yet know whether humans can thrive long-term in less than one 1G. We know that we can survive in 1G and that 0G causes many health problems but we have no experience, long term of anything in between.

Definitely, getting to Mars more quickly using nuclear rockets would be a huge advantage as we don't know if the astronauts will even be able to walk after a lengthy trip to Mars or how long it would take for them to recuperate in Mars' 38% gravity. Let alone the problems with dust once they got there.

If you are interested in the topic it is worth reading but note, even though it is a fairly contemporary book many of the projects it mentions have already been completed.

[Carlos · Rating 3 out of 5]

This was an interesting and accessible overview of what current and near term space exploration would look like. Wanjek is meticulous about showing the engineering difficulties, health risks and lacking motivations that have plagued space exploration since its height in the 1960s. He give the reader a brutally honest geostrategic context in which to understand the 1960s space race between the US and the Soviets and the first inklings of another race against the Chinese that may revitalize the US space program. He then gives realistic outlines of what it would take to go back to the moon, go to mars or even the rest of the solar system. He mostly sticks to the next few decades and takes the reader through the logical steps to ramp human presence in space and even the beginnings of an economic stimulus for it. Definitely worth the read for anyone who wonders what space exploration could look like in the next fifty years.

[Richard Jackson · Rating 5 out of 5]

A fascinating read. Not something to get through in a day or 2. The author takes a great deal of time explaining all the information we have on the moon, mars and the solar system and how we may someday seek to get leave our planet. What is great is he not only explains what is possible but what is not in terms of humans being able to withstand the rigors of many of these planetary environments. Similarly he also explains what could be done with just minor advancements in our current technology especially if we (humans) worked in synergy with each other rather than at cross purposes. I think anyone with a interest in space travel would be well served to read this one.

[Jake · Rating 5 out of 5]

Have you ever wondered why humans aren't further developed in the field of space exploration than we are currently? Have you questioned when, why and how we will see future space progress in our lifetimes? Do you wonder what life in space will be like for your descendants and what role it will play in Earth's economy? This book has clear, convincing arguments backed by good evidence for all these questions and a million more that you didn't know you had. You'll learn a ton about space, science, history, and more.

[Andrew Garvey · Rating 5 out of 5]

A fascinating, wide-ranging and accessible, clearly argued summary of the technological, economic and political opportunities in, and barriers to, exploring, exploiting and settling on the Moon, Mars and every other planet in our solar system (along with a variety of moons, comets and asteroids), Wanjek's book is a tremendous overview of a subject that takes in history, near-futurism and outlandish science fiction. I learned a lot and would definitely re-read it.

[Jonathan · Rating 4 out of 5]

I’m glad I came back to this while I have my audible sub. It was really interesting and informative. I don’t know how much I actually managed to absorb but I enjoyed listening to it nonetheless and honestly I wouldn’t mind listening to it again sometime in the future. It covered almost everything you can think of and more but never felt too overwhelming. I guess it helps that I’m already a huge space fan of both fiction & non-fiction!

[Faolitaruna · Rating 5 out of 5]

Most excellent, but wildly optimistic but comprehensive summary of prospects for space exploration.

The author is way too fast to believe such conmen like Elon Musk or Robert Zubin, but they are minor figures in the book.

[David Meyer · Rating 4 out of 5]

The occasional attempts at humor fall flat, and the opinions shared sometimes come off as oddly catty, but overall the book works well. The topic is taken seriously and the information presented is grounded in science in a meaningful way.

[Mattaniah Gibson · Rating 4 out of 5]

An excellent read, I enjoyed the grounded but imaginative approach to answering questions about the future of space travel. The comparisons to polar exploration were very helpful.
Four stars because Wanjek unfortunately buys into the Darwin myth but this does not impact the over all work.

[Sardonyx · Rating 5 out of 5]

This was a very pleasant reading experience. I daydreamed about gas giants and comets and planets lacking atmospheres when I wasn't reading the contents of this book.

[Scott Goldie · Rating 5 out of 5]

Excellent book. Detailed, interesting and really quite funny in places.

[Steve Lee · Rating 5 out of 5]

A thoroughly enjoyable read that fully met my expectations and matched my interests.