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Posts from the ‘Science and Technology’ Category

A New Space Race? Con’t.

By Taylor Marvin

Daryl Morini has a thoughtful response to my piece challenging his previous argument in The Diplomat that a new space race between America and a growing China is likely in the near future.

I think the core of our disagreement comes down to the likelihood of China jumping the gap between a purely military “ASAT race” and a prestige driven exploratory competition, motivating a newly-revitalized American space effort in response. Morini argues that as China grows wealthier and more technologically capable, this jump is likely:

“But if money is the sinews of war, then this space race will be more formidable than the last.

The U.S.-China competition is not about ideology; perhaps the Cold War never truly was either. Regardless, this modern great power stand-off has the potential to redefine the international pecking order. The motive of prestige – associated with great power status since nations went to war over diplomatic protocol and seating orders – will drive the new space race as it did the last.

Those who point to this time being different to the Cold War are right. But this is the main difference: China has the economic foundation and perhaps ambition to see this race through. This might yet fuel the U.S. motivation to run it, too. Ignoring the problem is not a prudent option.”

Do read the whole piece.

‘Through Struggle, the Stars’: What’s a Interstellar Humanity Look Like?

By Taylor Marvin

I just finished John J. Lumpkin’s excellent novel Through Struggle, the Starsand highly recommend it. In addition to being a very respectable first novel by an excitingly original author Through Struggle, which depicts a — to steal Rick Robinson’s term — plausible mid-future interstellar conflict, admirably tries to accurately depict realistic space combat. Set in 2139, the novel attempts to plausibly extrapolate a future global political and economic system incorporating extensive off-world colonization, and with the exception of “limited” wormholes (the opening must be physically transported to its ultimate destination;  meaning a roughly ten light year travel limit and no causality violations) the space technology does not violate our understanding of what’s possible.

While the novel’s protagonist is engaging and the narrative interesting, Lumpkin’s worldbuilding is what I found most intriguing. In imaging humanity 130 years in the future Lumpkin reaches some interesting conclusions. Some I find plausible, others less so. Some scattered thoughts [no spoilers]:

Lumpkin has obviously thought a lot about the the shape of human society over a century into the future. The United States of 2139 is refreshingly multiethnic, with lots of Hispanic names in evidence. It’s also mentioned offhand that the average skin tone of Americans is a “light brown”; again, an encouraging acknowledgment of the US’ changing ethnic makeup. However, the humans the 22nd century seem to be very similar to today’s: aside from retina displays, little “posthuman” genetic augmentation, technological implants, or pharmaceutical alteration is seen. To be sure, social factors will probably play a greater role in determining the future prevalence of posthuman-type augumentation than technology, but their absence feels strange.

Through Struggle depicts a world where nation-states have extensively colonized nearby systems — China, Japan, the US, and UK, among others, are all shown to possess colony worlds home to millions of people (the US is 52 states strong; presumably two are off-Earth). The international order of Through Struggle is significantly more adversarial and unstable than today’s. Lumpkin cleverly suggests that off-Earth activity is destabilizing: individuals who mature in mono-ethnic colonies are more bigoted than those on Earth, and mercantilist trade between nations and their colony worlds has reduced international trade.

I’ve previously discussed why I find mid-future space colonization implausible: current humans don’t seem to meet the requirements of an expansionistic species, and living off-Earth will always be more expensive and less comfortable than remaining in the cradle. Lumpkin partially adresses these concerns by implying that colonization is more driven by a Scramble for Africa-style pressure to keep pace with competing states than rational expansion, but his depiction of colonizing “ranchers” lured off Earth by the prospect of free land seems antiquated at best. Population pressures sparked by extreme life extension could arguably justify off-Earth colonization — though I’m skeptical that humans will ever command the resources necessary to move a significant portion of humanity out of Earth’s gravity well — but Lumpkin never mentions life extension, aside from off-handed references to ‘sixty year’ careers.

In his imagined  future, the United States is a distant third ranked power behind China and Japan, which at the novel’s opening are on the brink of war. China’s global leadership position is more than plausible — in fact, it’s difficult to imagine any ‘not-awful/nation states exist’ future where China’s massive population doesn’t guarantee it superpower status. But Japan as a future superpower crosses the line from plausible to extremely unlikely, at least in my mind. Japan’s population is expected to fall to under fifty million by the 22nd century, and its strategic outlook will likely be dominated by attempting to counter growing Chinese regional hegemony — a future not conductive to attaining great power status. I understand that, for narrative purposes, Lumpkin requires the the novel’s American protagonists to not represent the world’s most powerful state. But assuming that the United States loses its position of global preeminence in the next century, India would be a much more realistic leadership choice in a bi- to multipolar world, alongside China.

I do find Lumpkin’s depiction of Iran as a future US ally credible. If China continues to grow economically and incorporates central Asia into its sphere of influence, a realist Iranian government could find closer ties with Washington an attractive counterbalance to Chinese influence, especially assuming (as Lumpkin seems to) that India remains a minor power.

In Lumpkin’s future, numerous nations field space combat fleets, including smaller states like Korea, Iran, various Latin American nations, and the UK. I find this very unlikely. Even assuming that technological progress, the advent of autonomous construction techniques, and off-planet economies of scale, interstellar spacecraft are extremely expensive. Today there’s only a single superpower capable of fielding a fleet of nuclear aircraft carriers, which are maybe an order of magnitude less complex than a starship. If the international order of a future starfaring humanity remains structured around competing nation states, I would expect only a few of the largest and richest countries to command the resources necessary to construct starships, if any elect to at all.

On the economic side, Through Struggle makes no mention of space elevators, even though constructing one would appear well within the technological and organizational capabilities of civilizations capable of constructing wormhole networks. I’m skeptical that the type of space economy that Lumpkin imagines is possible with out space elevators to ease transport out of Earth’s gravity well. This seems a missed opportunity for geopolitical drama as well: in a balkanized world nations without territory along the equator would have a much more difficult time constructing an elevator of their own, an enormous strategic handicap. (Most designs for space elevators rely on centrifugal force from Earth’s rotation to support the elevator, meaning they must be built near the equator).

Through Struggle is a war story. This raises some problems; while speculating about future space combat is an interesting thought experiment, there are reasons to suspect that open, large-scale wars in space are unlikely. Almost by definition, a future politically stable and rich enough to build starships means a world where humanity will continue to grow wealthier and more educated, and presumably be less inclined towards major wars. Starship construction also arguably implies post-scarcity, reducing the material payoffs from victory. If we accept the common ‘naval warfare as space warfare analog’ premise, then the fact that humanity has not fought a naval war in seventy years is also certainly suggestive.

Another barrier to open space warfare is the cost of space assets themselves. As previously mentioned, spaceships are very expensive, and likely always will be. Today the cost of major naval combatants has kept a global blue water navy the sole preserve of the United States since World War II — even the Soviets were unwilling to attempt to gain the US’ naval power projection capabilities, preferring to invest in asymmetrical sea denial assets like submarines and anti-ship missile systems. China appears to be following a similar path today.

Following this analogy, the first nation to field space combat forces would enjoy a massive advantage, perhaps one strong enough to steer potential rising adversaries towards “space-denial” asymmetric strategies rather than a “black-space” power projection force. Similarly, space combat assets could be so expensive that militaries are loath to risk them, and adversaries refrain from directly targeting opponents’ major assets out of fear of mutual losses or escalation.

That said, what would space combat look like? Fiction provides plenty of examples. Despite fielding directed energy weapons and immensely powerful engines, the warships of Star Trek and Star Wars inexplicably engage at extremely close range. The (comparatively) primitive warships of 2004’s Battlestar Galactica similarly close to a few kilometers before pounding away with artillery and defending themselves with close-in weapons systems similar to those modern navies use today (in the vacuum of space conventional artillery is a perfectly credible weapons scheme). However, while dramatic these depictions of space combat aren’t that realistic.

Lumpkin’s depiction of space conflict is obviously very carefully researched, and is impressive. Like Rick Robinson and Winchell Chung, Lumpkin discounts the possibility of stealth in space — a spacecraft will always be a hot target against a very cold background, with detection ranges in the millions of kilometers, at least. However, unlike Lumpkin I’m not convinced that stealthed weapons systems are impossible, at least under certain conditions. As some of the commenters at Robinson’s blog have speculated, it could be possible to soft-launch an missile actively cooled to the temperature of the cosmic background from a ship that wouldn’t accelerate until it was within the minimum kill range of the target’s defensive close-in weapons systems. Such a missile would be very hard to detect. However, I’m skeptical about the real world combat utility of stealthed kinetic missiles. To maintain a low signature, these weapons would have to maneuver by using their liquid helium cooling fluid. But this type of thruster would be capable of only low delta-v, making it very difficult for a low observable cold weapon to catch a maneuvering target at all, even if the target never knew it was there!

Here Lumpkin’s mix of lasers, nuclear and conventionally armed missiles and kinetic weapons is accurate. One use of stealthed remotely-fired weapons he doesn’t mention is nuclear-pumped x-ray lasers. One ship could eject several of these devices, which would then move laterally away from each other. Before firing they would be largely undetectable, negating the danger of counter-laser-lasers damaging your laser system, a frequent occurrence in the novel.  Firing several at once from different angles would increase the chances of killing the enemy ship, and the firing could be timed to coincide with the impact of kinetic weapons, similar to the Russian air combat practice of firing two missiles with different targeting systems at a single target to increase the chance of a kill. These weapons would be a low-cost augment to Lumpkin’s ship-based laser systems and mass drivers.

These speculative differences aside, John J. Lumpkin has authored an impressive debut novel. I highly recommend it.

A New Space Race? Not So Fast

By Taylor Marvin

A vision of what’s to come? NASA photo.

Over at The Diplomat, Daryl Morini has a though provoking piece arguing that NASA’s dramatic Mars Science Laboratory mission foretells “the coming US-China space race.”

To be sure, high profile NASA successes carry a nationalistic subtext. A failure of the highly-public Curiosity lander, in the words of prominent Mars exploration expert Robert Zubrin as paraphrased by Sydney Morning Herald writer Michael Hanlon, “could have meant effectively an end to the US venturing into space for at least a generation, and the keys to the solar system would have been handed to the Chinese.”

Zubrin’s warning is certainly grim, but is wildly overblown. The loss of the Curiosity lander would have been a major blow to the American planetary exploration program. But handing “the keys of the solar system” to the Chinese?* Unlikely — aside from Curiosity, NASA and the European Space Agency currently have four operational orbiters or rovers studying Mars: the 2001 Mars Odyssey, Mars Express, and Mars Reconnaissance Orbiter spacecraft, and the MER-B Opportunity rover. More importantly, this prediction underestimates just how important the trail-and-error experience is to successful space exploration, which China’s young space program lacks. China has never successfully dispatched an exploratory mission to Mars, and the recent launch failure of the joint Chinese-Russian Yinghuo-1/Fobos-Grunt probes reemphasizes how difficult these missions really are. We have every reason to expect Chinese exploratory successes in the future, but it’s worth remembering that the US and Russia’s dramatic successes in space are based on decades of painful but informative failures.

The Unites States has been dispatching missions to the Red Planet since the 1960s, missions that have grown more complex and less failure-prone over time. It’s likely that NASA’s recent string of dramatic Mars successes is due to technical and managerial lessons learned during the agency’s equally dramatic — and humiliating — failures in 1998 and 1999. For example, investigations in the wake of the loss of the Mars Polar Lander related Deep Space 2 impactor found that NASA projects were consistently under-resourced and under-tested, and a 2001 internal audit reported that Mars programs conceived under the 1990s ‘Faster Better Cheaper’ cost-cutting mantra lacked “appropriate number of staff or competencies needed to effectively carry out its strategic goals and objectives”. Today’s NASA Mars probes, which have not experienced a major failure since 1999, benefit from this experience. Even if Curiosity had failed, it will take decades of Chinese space exploration for the PRC to build up the institutional knowledge and experience NASA benefits from.

More importantly, Morini argues that the success of Curiosity and China’s nascent space ambitions herald a new space race:

“This amazing feat in human space exploration is revealing of the geopolitical context back on Planet Earth. In particular, this event marks a milestone in the present trend of an expanding US-China rivalry, and a budding military-technological space race.”

The last space race put humans into space, and left footprints on the moon. America and China are beginning to militarily compete in space, but the term “space race”, with its grand historical allusions, poorly characterizes this rivalry. In fact, I’d be very surprised if the US-China geopolitical rivalry likely to dominate this century results in a space competition similar to the Cold War’s, for numerous reasons.

First off, the US-Soviet space race was enormously expensive. At its peak the Apollo moon program consumed 2.2 percent of federal outlays; while figures for the Soviets are hard to come by, a combination of chronic resource shortages in the Soviet space program and a tangled bureaucracy crippled the Russians’ moon shot despite the Soviets’ impressive engineering credentials. Uncrewed exploratory probes were also expensive, though of course paled in comparison to crewed space programs. The massive government pushes of the space race were only possible because the conflict between the US and USSR was so intense — remember, while American and the Soviet engineers were scrambling to put a man on the moon there was a distinct possibility that their two countries could blow each other to hell at any moment.

Curiosity on its way to Mars. USAF photo by George Roberts, via Wikimedia.

Fortunately, the rivalry between economically interdependent America and China is nowhere near as severe its Cold War predecessor, and has little prospect of becoming so. This makes it difficult to imagine America’s rivalry with China justifying massive space expenditures. Furthermore, the space race of the Cold War was a competition played for external audiences just as much as domestic consumption: both the US and USSR sought to demonstrate their system’s scientific and industrial superiority to non-aligned nations. Outside of the bipolar international structure of the Cold War, these audience considerations have less merit; Washington and Beijing alone will not dominate this century’s world affairs to the extent that the rivalry with Moscow did during the second half of the 20th.

The relatively balmy relations between Washington and Beijing make aggressive space expenditures unlikely. As I argued earlier this year [slightly edited for clarity]

“The Apollo program was an enormously expensive effort, costing $98 billion over 14 years. Yes, this expenditure is dwarfed by the US defense budget — in 1969 alone the US spent nearly $500 billion in 2009 dollars on military spending — but 2.2% of federal spending comes with large opportunity costs. Governments don’t spend these kinds of funds lightly, especially if there’s little apparent electoral benefit from massive space spending. The Apollo program only scraped above a 50 percent approval rating in the immediate aftermath of the Apollo 11 landing, and without the external Soviet threat it’s unlikely that the massive space expenditure of the 1960s would have been possible.”

Without a dramatic, and unlikely, worsening in US-China relations it is difficult to imagine any political appetite for these kind of expenditures.

It’s also difficult to imagine the target of a US-China space race. Transient excitement over Curiosity aside, uncrewed space exploration just doesn’t capture the hearts of the world: few people will retell where they were when Curiosity landed to their children. To be sure, competition between the US and Soviet space programs included unmanned planetary exploration, but these probes were always a minor — and often publicly ignored — chapter in the space race. After all, while most Americans today can likely identify that the USSR launched the first man into orbit (hopefully!), few are aware of the Soviets’ impressive successes landing probes on the surface of Venus.

A return to the Moon is a natural target for a US-China space race. However, I’m not sure the Moon retains a powerful draw. Sending taikonauts to the Moon by 2030 is an official goal of the Chinese space program, but replicating an American achievement half a century old doesn’t exactly fit the dramatic definition of a space race. Even establishing a manned base on the moon, the eventual goal of the Chinese lunar program, is unlikely to stimulate a competing American base. A permanent human presence on the moon is of little scientific value and, contrary to many claims, would be of little use as a base for expeditions to Mars or other extraterrestrial targets. Similarly, mining operations on the Moon are likely decades away. China may go through with its lunar goals — though it’s worth remembering that very few grand long-term space goals articulated by any national space agencies ever progress beyond the paper stage  — but it is unlikely that replicating the US lunar landing in grander form will motivate aggressive competing American space spending.

Mars, of course, is the logical target of a US-China space race; a crewed mission to Mars by either country would be a truly impressive accomplishment. But just as the technical difficulty of Apollo far surpassed those the earlier Vostok program faced, a crewed mission to Mars would be far more difficult, dangerous, and expensive than traveling to the Moon. A crewed Mars mission would require major advances in spacecraft and mission design, and keeping humans healthy during the isolated and radiation-heavy four to eight month (depending on the propulsion technology used) trip to the red planet is a daunting challenge. A crewed Mars program would require numerous heavy lift launches and establishing a comsat system around Mars, and more ambitious mission designs require advances in orbital construction. These difficulties do not mean that crewed missions to Mars are impossible, but it is worth noting that the Apollo program is not a good predictor of their cost or difficulty. Colonizing space — which Morini likens to the pre-WWI Scramble for Africa — is even more expensive, and technically challenging.

Secondly, the space race of the Cold War was not solely an exercise in peaceful competition. Instead, the space race was an organic outgrowth of the missile race between the US and USSR. As Greg Goebel’s extensive history of the space race emphasizes, early investment by Washington and Moscow in rocket technology was motivated by the desire to develop intercontinental ballistic missiles; Sputnik, humanity’s first satellite, was launched almost as an afterthought. The real focus of both programs was fielding missiles capable of heavy throw weights, and later on developing rockets capable of putting heavy spy satellites in orbit. Of course, a rocket capable of carrying a heavy warhead across the world is not conceptional very different from one capable of lifting a civilian payload to orbit. While the extremely heavy-lift rockets of the later moon race had no connection to military use, they leveraged off technologies developed in the missile race — technologies like working solid and liquid fueled engines, staging, and ablative reentry heat shields all grew out of early ICBM design. It is doubtful that the Cold War space race would have taken off the way it did if the military enthusiasm for early rocket development didn’t guarantee funding for nascent space programs.

Does the current military rivalry between the US and China reflect this dynamic? Not really. The military already has ICBMs and spy satellites, and little motivation to invest in further innovative space projects, at least compared to the innovation of Cold War rocket development. The technological developments necessary for more ambitious US/Soviet space race-style exploration have no relevance to today’s militaries. If another true space race occurs, politicians must justify it entirely on civilian grounds.

Morini focuses on this military rivalry, cautioning against forgetting “the military significance of technological superiority in space in any modern war.” This is certainly true. China is heavily investing in anti-satellite weapons as part of its asymmetric area-denial/anti-access strategy, the US Air Force recently developed the impressive X-37 uncrewed spaceplane, there is the future possibility of the US and China competing to acquire the ability to mission-kill each other’s surveillance satellites, and a broad area maritime satellite surveillance capability is a requirement for China to operationally deploy its anti-ship ballistic missile capability. However, unlike during the Cold War this is a rivalry of deployment rather than innovation. The US and USSR both possessed rudimentary to advanced anti-satellite capabilities during the Cold War, though both sides avoided frequently demonstrating their capabilities for fear of creating dangerous orbital derbies. Current space militarization is more accurately characterized as expanding neglected existing capabilities than truly pushing the technical envelope. While the rivalry between the US and China could lead to fielding more comprehensive anti-satellite capabilities, it’s difficult to term this a “space race” — certainly when compared to the theatrics of the Cold War. While this may be a question of semantics, I have trouble believing that the public will acknowledge that competing surveillance and anti-satellite systems warrant the title.

If you define a space race as gradually improving space military capabilities, then yes, one is “now in full swing”. But the Space Race of the Cold War, where the US and USSR competed to match each others dramatic and daring exploration, is a memory and one’s that’s unlikely to soon be repeated.

*Note that these aren’t Zubrin’s direct words; I was unable to find the direct quote Hanlon paraphrases. Also note that Zubrin is a long-time advocate of crewed missions to Mars (check out his excellent book The Case for Mars), and certainly has an incentive to play up fears of a new space race.

The Future of Driverless Cars

By Taylor Marvin

Kevin Drum flags a provocative quote from Alex Tabarrock on the future of driverless cars:

“At first when there is an accident people will ask, ‘did he have the driverless option on?’ But soon they will start to say ‘if only he had the driverless option on.”‘

There’s a fun parlor game — apologies, I can’t remember where I first saw this — in trying to imagine what aspects of our society future generations will judge as barbaric. We’re appalled that the earlier generations accepted slavery and racism as the natural order of the world, and often enthusiastically supported eugenics. What do we accept without thought that future generations will look upon with horror?

Typical answers include eating animals, punishing crimes with isolating prison sentences, and so on. However, I’ve always thought that future generations will be amazed that we let nearly everyone drive a car, and accepted over 30,ooo motor vehicle deaths a year as perfectly normal. Of course, the freedom of private cars, and their costs, are a valued and necessary part of our society. But when driverless cars come into their own in the next few decades, I’m certain that the expectation that traffic deaths are a part of life will change.

Reconsidering “First Contact”

By Taylor Marvin

Staying on the subject of aliens, what would a human first contact with an intelligent alien species be like? Science fiction typically presents two possibilities: violent confrontation, or cooperation that benefits humanity — think human’s first contact with the Vulcans in Star Trek, whose good example led to the banishment of human violence and poverty. In any case first contact is nearly always assumed to have a unprecedented effect on the human experience.

However, both these scenarios assume direct contact, and communication, between us and the aliens.  This is unlikely. Instead, human “encounters” with aliens are much more likely to be discoveries of distance evidence of extraterrestrial civilizations.

How would humans react to such a discovery? I’m not convinced the results would be especially dramatic. Let’s imagine that next week astronomers detect a discarded debris shield from an alien spaceship by pure chance zipping through our solar system. If this shield is similar to the one utilized on the proposed Project Daedalus fusion interstellar probe, it would be a 50 ton beryllium disk — not a particularly informative artifact, even if we could examine it in detail. Assuming the shield(s) traveled independently just in front of the alien spacecraft — Project Daedalus does not use this scheme, but increasing the distance between a shield and the main body of a spacecraft could increase protection from interstellar debris — the shield would continue on its path after the spaceship decelerated, and would spend only a short time in the solar system before continuing on its way.

The Project Daedalus spacecraft, compared to a Saturn V rocket. Note the meteor shield. Image via Icarus Interstellar.

My point is that while encountering such a shield would be absolute proof of an intelligent alien civilization, it would tell us next to nothing about who created it. All we would know is that sometime in the last 9 billion years an interstellar alien civilization did exist, and that they utilized spacecraft roughly similar to those proposed by humans — that’s it. What effect would this knowledge have on humanity?

Of course it’s impossible to tell, but I suspect not much. Knowing that someone else is — or, more likely, was — out there would challenge humanity’s understanding of its place in the cosmos, but probably would not dramatically alter human culture. In contrast to Star Trek’s wide-eyed optimism, humans’ propensity for conflict would likely continue. Beyond that, who knows?

Exploring the repercussions of such a fleeting encounter could make a great premise for a short story.

What Would an Expansionist Alien Species Be Like?

By Taylor Marvin

One of the more interesting questions about the universe is the apparent rarity of intelligent life. It is reasonable to suspect that given the vast size of the universe and apparent frequency of rocky planets intelligent civilizations are common in galactic habitable zones, even disregarding the possibility of exotic biologies. However, humans have not encountered aliens and observed no evidence of these civilizations, despite the fact that evidence of both extant and extinct sufficiently advanced civilizations should be apparent across galactic distances. This is especially puzzling because today’s humans are not far from the technological requirements — conservatively, fusion drives and generation ships — required to colonize a significant portion of the galaxy.

This puzzle — if aliens are common, where are they? — is termed the Fermi Parodox. Scientific America author Ian Crawford elegantly summarized the possible solutions to the paradox:

“There are only four conceivable ways of reconciling the absence of ETs with the widely held view that advanced civilizations are common. Perhaps interstellar spaceflight is infeasible, in which case ETs could never have come here even if they had wanted to. Perhaps ET civilizations are indeed actively exploring the galaxy but have not reached us yet.

Perhaps interstellar travel is feasible, but ETs choose not to undertake it. Or perhaps ETs have been, or still are, active in Earth’s vicinity but have decided not to interfere with us. If we can eliminate each of these explanations of the Fermi Paradox, we will have to face the possibility that we are the most advanced life-forms in the galaxy.”

There’s a lot to explore here, but I’d like to focus on two of the four potential answers: that intelligent civilizations are chose not to expand through the galaxy, or are somehow prevented from doing so. Importantly, it appears that this “prevention” is not based on an inherent difficulty of interstellar colonization. Again quoting Crawford:

“Any civilization with advanced rocket technology would be able to colonize the entire galaxy on a cosmically short timescale. For example, consider a civilization that sends colonists to a few of the planetary systems closest to it. After those colonies have established themselves, they send out secondary colonies of their own, and so on. The number of colonies grows exponentially. A colonization wave front will move outward with a speed determined by the speed of the starships and by the time required by each colony to establish itself. New settlements will quickly fill in the volume of space behind this wave front.”

In a famous 1998 paper “The Great Filter – Are We Almost Past It?”, economist Robin Hanson suggests that humans do not observe aliens because life encounter a “great filter between death and expanding lasting life” that prevents it from colonizing the galaxy.

“No alien civilizations have substantially colonized our solar system or systems nearby. Thus among the billion trillion stars in our past universe, none has reached the level of technology and growth that we may soon reach. This one data point implies that a Great Filter stands between ordinary dead matter and advanced exploding lasting life.”

Either intelligent life evolves extremely rarely, or it is extinguished before expanding. While Hanson believes this filter is best explained by the presumed rarity of the evolution of intelligence, he provides a fascinating description of social hypothesis that explain the theorized short lifespan of intelligent civilizations. Interestingly, as humans appear to be relatively close to interstellar capability, this suggests that — rejecting a biological Great Filter mechanism — that humans are also close to encountering the Great Filter.

Confounding the puzzle, Hanson argues that evolutionary theory suggests that civilizations that do arise tend towards expansion, making their absence harder to explain:

“In general, it only takes a few individuals of one species to try to fill an ecological niche, even if all other life is uninterested. And mutations that encourage such trials can be richly rewarded. Similarly, we expect internally-competitive populations of our surviving descendants to continue to advance technologically, and to fill new niches as they become technologically and economically feasible.”

Hanson argues that energy constraints, desire to outpace potential competitors, and concerns over local disasters would motivate even sedentary civilizations to expand — the galaxy is not full of hermit civilizations. Similarly, the finite lifespans of main-sequence stars would eventually force all civilizations that reach the end of their sun’s life to expand or die. This suggests that most intelligent civilizations eventually expand, leading it to the Fermi paradox — if intelligent civilizations are common and expansionist, why don’t we observe them?

There are three broad possibilities: aliens are expansionist but hide, either on purpose or inadvertently; civilizations are routinely destroyed before they can expand; or that civilizations elect not to expand.

Because evidence of advanced civilization is typically thought to be detectable on galactic scales, if expansionist civilizations exist in our galaxy something must be preventing us from detecting them. Typical explanations include that we have detected but cannot recognize evidence of very alien extraterrestrial civilizations for what it is, by chance aliens avoid technology detectable over vast distances, or that the galaxy is dangerous and technological civilizations are actively hiding.

Another possibility: rather than electing not to expand, planets are somehow routinely prevented from developing interstellar civilizations. Science fiction suggests a few fictional answers. In Alastair Reynolds Revelation Spacenascent interstellar civilizations inevitably attract the malevolent attention of the “Inhibitors”, dormant machines left over from an early interstellar war, or, more fancifully, in Charles Stross’ A Colder War ill-advisedly meddle with H.P. Lovecraft’s monsters. Other commonly theorized dangers are nuclear or biological warfare, or environmental disaster. More exotic theorized perils include civilization-destroying experiments with strong artificial intelligence, or attracting the attention of rapacious hidden aliens (I find this unlikely).

Another potential “Great Filter” mechanism is that alien civilizations do arise, are not prevented from expanding but instead elect not to. There are numerous explanations for this tendency. An early, widespread alien civilization could have imposed a “no-expansion” norm on following civilizations; Reynold’s long-lived Inhibitors could be considered a particularly violent way of enforcing this norm across deep time. Civilization could be universally cautious, and avoid expansion at all costs for fear of attracting the attention of hidden malevolent aliens; however, it is difficult to reconcile this with the death of stars — why would a solar system-bound civilization fear a potential danger over certain death at the end of their sun’s life? Alien civilizations could also universally prize preserving the natural state of the galaxy, though again it is doubtful that this naturalistic impulse would survive the death of civilization’s stars. Or, advanced civilizations could universally embrace virtual reality or lose physical form while somehow avoiding the resource and survivability incentives to expand.

Another potential solution is that advanced civilizations commonly arise, but are prevented from expanding due to for purely economic or organizational reasons; in this case, the solution to the Fermi paradox would be the “it is too expensive to physically spread throughout the galaxy” hypothesis. As Hanson notes, there are numerous problems with this theory; most notably, evolutionary pressures tend to select expansionary traits in successful or long-lived societies. However, I’d like to examine this possibility in more detail: why would civilizations chose not to expand in the absence of external pressures (previously set non-expansion norms, fear), innate non-expansion traits (tendency towards naturalism), or disinterest (move to virtual reality without a local resource constraint, etc.)?

There are clearly long-term benefits to galactic expansion. Civilizations that do expand would have access to much greater energy resources and vastly increased security. However, it is important to remember these benefits are collective, long-term benefits, and species with finite lives have little reason to invest in the extreme long-term. If we restrict our discussion to human-like species composed of reproducing, autonomous, sentient individuals, it is possible to argue (speculatively!) that the drive for galactic expansion largely vanishes. Interstellar colonization is a collective effort that likely fails a human-based cost-benefit test scaled around a few human generations; when rational short-lifespan individual utility maximizers are the decisionmakers, under conditions roughly similar to foreseeable future humanity interstellar colonization seems unlikely. It is even possible that individual species like our own would be unable to organize interstellar expansion when motivated by the impending death of their sun.

I am not arguing that the “it is too expensive to physically spread throughout the galaxy” is a particularly convincing universal solution to the Fermi paradox, but instead that economic constraints are a more likely explanation for supposing that near-baseline humans will not expand widely in the foreseeable future than astronomical or social-triggered destruction.

Of course, “conditions roughly similar to foreseeable future humanity” benchmarked on the early 21st century certainly leaves a lot of leeway for future humans, not to mention other species broadly similar to our own. That said, we can broadly speculate about the qualities of expansionist species with biology (again, reproducing, autonomous, sentient individuals) similar to our own:

  • Exponential reproduction: In the last half century the world total fertility has fallen precipitously, from a mean of 4.95 in the 1950-55 era to 2.36 today. This fall is well understood, and is associated with the advent of birth control, rising incomes, and women’s’ increased social empowerment and education. But importantly, falling total fertility is only possible because birth control allows sex to be decoupled from reproduction, and the human reproductive drive is a sex drive. It’s entirely possible that an alien species would have a reproductive, rather than sex, drive that negated the entire idea of birth control and made exponential population growth difficult to avoid. Massive population growth could be a powerful incentive to invest in interstellar expansion.
  • Extreme life extension: I’ve previously wondered if human’s falling birthrates would prevent humanity from ever investing in space colonization — after all, barring some catastrophe living in off-world will in the medium-run always been more expensive and uncomfortable than living on Earth. If humans don’t have a pressing reason to leave in large numbers, they likely won’t. While human colonies off of the Earth would significantly improve the survivability of the human species, it’s difficult to imagine this is a sufficient reason to motivate investing in these colonies. However, medical advances resulting in extreme life extension would undo the population control gains from stable world total fertility and again raise the specter of global overpopulation, perhaps prompting investment in off-world colonization. The same logic could apply to other species.
  • Competing local societies: As Hanson notes, competition creates strong pressure to expand into unexploited niches. Competition among local societies could create incentives to expand in otherwise non-expansionistic species. However, it is difficult to imagine sufficient competition among human-like species to prompt interstellar expansion while avoiding local war that destroys the capability for extensive interstellar travel, though perhaps strong prohibitions on armed conflict could avoid this.
  • Innate expansionistic tendencies: To move into more speculative factors, it’s possible to imagine alien species with an innate desire to expand — just as human behavioral evolution appears to have favored aggression. An innate desire for expansion would motivate investment in colonization beyond that justified by human cost/benefit calculations.
  • Low/High risk tolerance: Space exploration is risky, both in direct risk and its high opportunity cost. Space colonization is much more risky. It’s conceivable that a species with a higher innate psychological tolerance for risk would elect to invest in risky expansion for reasons that don’t make sense to humans. Conversely, an species with a tolerance for risk much lower than humans could judge the long-term security of space colonization worth the risk and opportunity cost. Lifespan could conceivable play a role as well; assuming species consisting of sentient individuals, longer-lived species could either have lower (more to lose) or higher (boredom) tolerance for risk than humans.
  • Extreme technological advancement: All of these previous traits alter the benefit side of an expansion cost/benefit ratio. However, extremely advanced technology developed for other purposes could justify expansion by radically reducing the cost of expansion. For example, self-replicating von Neumann machines could make expansion much cheaper. This relative affordability could prompt highly advanced species to expand when they otherwise would elect not to.

If this theory holds (and I’m not entirely convinced that it does; for example, extreme life expansion could be very common even in relatively young intelligent species), we would expect human-type civilizations that do expand to be dominated by those with innate high population growth, or extremely high technological capabilities (i.e. no expensive generation ships or warp drives). More speculatively, we could expect the most expansionist species to be those where policy is not set by individual utility maximizers. These “non-individually rational” species could include hive minds a la Star Trek’s Borg, machine races, or something else entirely.

If we accept the argument that species composed of short-lived, individual utility maximizers are not particularly inclined to expansion, and these civilizations tend to not delegate social decisions to non-individual utility maximizing actors like “God computers”, then a potential solution to the Fermi Paradox is that civilizations with the expansionist traits listed above arise only rarely. This, however, does not address the problem that expansionist societies would tend to out-compete and displace non-expansionist societies.


The Cloud Makes Facebook Durable

By Taylor Marvin

Alexis Madrigal makes a convincing case that Facebook’s business model is durable, despite its fiasco of an IPO. In particular, Madrigal argues, comparing Facebook to the defunct MySpace isn’t informative, because Facebook enjoys a huge international monopoly that would be extraordinarily difficult for an upstart competitor to challenge:

“It has long been trendy to compare Facebook to MySpace and Friendster, two social networks that were once dominant. But let’s get real here. There’s dominant and there’s DOMINANT. No social network has ever commanded a greater share of Internet users, their time, or their shared media. And it is not even close. MySpace got passed by Facebook when they had something like 120 million worldwide visitors a month. That makes Facebook 7.5 times larger than MySpace ever got. Friendster? They were in the single-digit millions.”

Social media users, especially influential young consumers, are finicky, and it’s easy to imagine some users abandoning Facebook for a newer competitor that’s perceived to be more exclusive. However, Facebook’s enormous user base — nearly 1/7th of the entire human species — is an enormous barrier for a smaller competitor to overcome.

In addition to Facebook’s much larger market penetration, the way people share photos on Facebook makes it difficult for them to leave the site:

“And it’s not just *your* photos that matter on Facebook. It’s all those photos other people have taken of you and your friends. That means you can’t simply take your ball and go home; all the other memories captured by friends that you have easy access to through the system? You can’t have them without everyone sitting on the same system.”

This is an important feature of Facebook’s durability, and I think the social media’s approach to storing photos has fundamentally changed since the period of MySpace dominance. Before Facebook, social media users primarily stored photos on their own hard drives, rather than on social media servers. Today that’s different: faster internet connections and lower server costs mean that most Facebook users use the site as their primary photo storage option, rather than their own computer. This is especially true after the advent of smartphones, which removes computers entirely from the photo to social media uploading process. If a Facebook user leaves the site they aren’t just losing access to photos other people have taken of them, but to any of their own photos not stored elsewhere. Of course, it’s possible to download individual photos, but it’s time consuming and Facebook doesn’t provide an easy way to download entire albums — probably deliberately. It’s in Facebook’s interest to make it as inconvenient to leave the site as possible, and as more and more users’ photos reside exclusively on Facebook’s servers leaving the social network will become more difficult.

However, I’m really too young to be making this observation — I joined Facebook in 2007, and never used MySpace. Does this theory sound credible to readers who’ve used both sites?

Update: Michael Wolff has an interesting counterpoint (via Andrew Sullivan):

“On the one hand, Facebook is mired in the same relentless downward pressure of falling per-user revenues as the rest of Web-based media. The company makes a pitiful and shrinking $5 per customer per year, which puts it somewhat ahead of the Huffington Post and somewhat behind the New York Times’ digital business. (Here’s the heartbreaking truth about the difference between new media and old: even in the New York Times’ declining traditional business, a subscriber is still worth more than $1,000 a year.) Facebook’s business only grows on the unsustainable basis that it can add new customers at a faster rate than the value of individual customers declines. It is peddling as fast as it can. And the present scenario gets much worse as its users increasingly interact with the social service on mobile devices, because it is vastly harder, on a small screen, to sell ads and profitably monetize users.”

Read the whole thing.

“Putting Your Mind” to Space Industrialization

By Taylor Marvin

I’m currently reading my way through the works of Welsh science fiction author Alastair Reynolds. A standout is Pushing Ice, which chronicles a human mining crew in the outer solar system encounter an alien artifact. The novel begins in 2057, a date that seems a hopelessly optimistic time frame for routine exploration of the outer solar system. Pushing Ice was published in 2005 — Reynolds is only leaving half a century for the development of fusion drives, life support systems much more complicated than today’s, and the infrastructure to manufacture large spacecraft, presumably in orbit.

Reynolds has clarified that Pushing Ice’s near future setting is less of a forecast than a narrative tool to make the characters and setting more relatable to modern day readers (for comparison, the bulk of Reynold’s Revelation Space series is set in the 2600-2700s), and acknowledges critiques that question the plausibility of his timeline as perfectly understandable. However, Reynold’s argues rapid technological advances aren’t unprecedented, noting that the moon landing followed simple wooden aircraft by only half a century:

“Which, when you think about it, is pretty astonishing. Even more so when you appreciate that many of the key technologies of the Apollo program were essentially mature by the start of the 1960s. The Saturn F1 main engines were part of a program that originated in 1955, a full 14 years before the Moon landings – and a mere 36 after Alcock and Brown made the first non-stop crossing of the Atlantic in a Vickers Vimy.

So you can do quite a lot in 50 years, if you put your mind to it.”

This is a valid point — technological progress can occur extremely rapidly, and often in unpredictable ways. Science fiction authors, whose plots often require them to predict or at least image the future, are often acutely aware of their predecessors’ often hilarious mistaken predictions. In retrospect these are often obvious; the routine space travel of 2001: A Space Odyssey is hilariously — or depressingly — out of place today, merely 4o years after its 1968 premiere and a decade beyond its setting. The point here isn’t that these predictions were foolish but that it’s very difficult to forecast the direction that technological advancements will go; while science fiction authors of the mid-20th century were hugely optimistic about manned spaceflight, authors writing as recently as the 1980’s completely missed the huge advancements in information technology that completely revolutionized the last two decades. This oversight is understandable. All prediction involves some form of extrapolation, and it’s easy to superficially extrapolate our own contemporary assumptions to uncredible ends. Authors writing in the 1960s had experienced two decades of wild advances in human spaceflight that would have seemed unimaginable only a few years before, and saw no reason why these advancements would suddenly come to a grinding halt at the moon. Similarly, while it was possible to predict internet and massive data aggregation technologies, few foresaw how completely they have altered the modern world.

The problem with Reynold’s example is that technological progress doesn’t follow a linear growth pattern. It isn’t a question of saying that since humanity advanced from simple aircraft to the Apollo program in half a century that routine expeditions to the outer solar system will be possible in another fifty years. First, the technological requirements of an outer solar system-capable spacecraft aren’t a linear extrapolation of the advance from a Vickers Vimy to the Saturn V; it’s much more of an exponential jump. Reynolds is right to point out that the main technological hurdles of the Apollo mission were solved in 1955, and it’s arguable that humans possessed the necessary theoretical information to produce a moon rocket in the late 1940s. However, there’s a huge leap between theoretically simple and relatively easily machined F1 engines and a pulsed fusion drive. Arguably more complex is the life support systems, material sciences, and orbital manufacturing infrastructure required to construct large spacecraft. While a Saturn V was at its core a derivative of the early 1940s-era V2 ballistic missile, these technological requirements are fay beyond anything humans have ever pursued.

More importantly, viewing space capability advancements as a purely technological problem is a mistake. There’s a common tendency to look at capability gains in an organization through hardware, rather than the more important institutional software. Contemporary discussions of the Chinese military often suffer from this fallacy — it’s easy to talk about new ships and planes, and harder to discuss the institutional culture, communication systems, and officer corp that are much more important to the quality of a military force than their equipment.

The greatest achievement of the Apollo program wasn’t its the sum of its technological parts, but creating the organizational capability to bind hundreds of discrete technologies into one of the most complex engineering projects humans have ever attempted. In the nearly half century since the end of the Apollo program humans have become much better at managing large scale technological projects. However, outer solar system-capability needs to be understood as part of a larger infrastructural framework, one that is a much greater organizational challenge than building a fusion spacecraft. Building a large inter-planetary ship requires advanced orbital construction techniques, and intensive mining of the solar system probably requires an Earth space elevator to be profitable. Even with intense private competition there isn’t reason to suspect that the costs of reaching orbit will ever become economical as long as they rely on chemical rockets, and the technological barriers to cheap LEO will likely remain in to the foreseeable future.

It’s perfectly fine that Reynold’s sets Pushing Ice in the near future — after all it is fiction, and good science fiction’s assumptions should serve the story, not the other way around. However, it’s a mistake to view human space exploration outside of its political and economic determinants. Reynolds remarks that technology can advance quickly, “if you put your mind to it.” But the real issue is whether there’s sufficient motivation for humanity to put its mind to space technology. After all, the opportunity costs of space development are enormous, and the political barriers to large-scale government space development formidable. This isn’t a question of simple will.

The Apollo program was an enormously  expensive effort: costing $98 billion over 14 years at its height consuming 2.2% of the federal budget. Yes, this expenditure is dwarfed by the US defense budget — in 1969 alone the US spent nearly $500 billion in 2009 dollars on military spending — but 2.2% of federal spending comes with large opportunity costs. Governments don’t spend these kinds of funds lightly, especially if there’s little apparent electoral benefit from massive space spending. The Apollo program only scraped above a 50 percent approval rating in the immediate aftermath of the Apollo 11 landing, and without the external Soviet threat it’s unlikely that the massive space expenditure of the 1960s would have been possible.

Unfortunately, once you consider space development within an political economy framework incentives for high-opportunity cost space development tend to disappear. As I’ve argued before, stabilizing world demographics makes the prospect of significant human off-world settlements unlikely. Current UN medium fertility variant-projections forecast a human population that stabilizes at roughly 10 billion mid-century. Of course, there’s uncertainty in any forecast — notably, the 2004 UN population forecast predicted a 2100 world population of 9.1 billion, a figures that less than a decade later has been revised upwards by a billion, an 11% revision. But it’s hard to imagine a plausible scenario where a significant number of humans ever live off planet. Even assuming huge technological advances dramatically reduce the cost of space transport and allow for robust off-world industrial infrastructure, costs of living away from Earth will always be unimaginably high. On Earth atmosphere and surface pressure are free; anywhere else they aren’t. If the world population peaks this century there likely won’t be any pressing demographic reason humans have to live off planet, and it is difficult to imagine any other incentive to leave that satisfies any plausible cost/benefit criteria.

Like many science fiction futures, Pushing Ice avoids this problem by imagining industrial, rather than settlement, human activity in space. This is more plausible, but it is still difficult to imagine an economic environment that would justify intensive industrial activity off world. Even if most of the R&D funding for an outer solar system commercial mining fleet comes from private industry, huge government expenditures would be necessary to lay the infrastructural groundwork. It is possible that competition for increasingly scarce and economically vital rare earth elements could motivate increased space expenditures in the near future. But extracting minerals from asteroids will always be enormously expensive, especially in the absence of economies of scale. Large-scale mining that floods the market and forces down prices would be equally unprofitable. Both are barriers to private investment in space resource extraction, recent news aside.

I’m not arguing that a human future in space is improbable. But narrative considerations aside, Pushing Ice’s regular flights to the outer solar system are not probable this century, for reasons more economic than technological. Ignoring this reality isn’t a fault — after all, science fiction more concerned with government budgets and resource economics would be dry reading compared to encounters with aliens. But it is important for futurists to remember that human institutions, not technology, are the real barrier to space industrialization.

Say What You Want, the Galactic Empire Had Its Defense Procurement Down

By Taylor Marvin

Note: I’m not super familiar with the Star Wars universe. If I mess anything up don’t hesitate to call me an idiot.

Kevin Drum ponders the Death Star, and concludes it’s a cost-effective investment:

“I figure that the price tag on the latest and greatest Ford-class supercarrier is about 100x the cost of the raw steel that goes into it. If the Death Star is similar, its final cost would be about 1.3 million times the world’s GDP.

But there’s more. Star Wars may have taken place “a long time ago,” but the technology of the Star Wars universe is well in our future. How far into our future? Well, Star Trek is about 300 years in our future, and the technology of Star Wars is obviously well beyond that. Let’s call it 500 years. What will the world’s GDP be in the year 2500? Answer: assuming a modest 2% real growth rate, it will be about 20,000 times higher than today. So we can figure that the average world in the Star Wars universe is about 20,000x richer than present-day Earth, which means the Death Star would cost about 65x the average world’s GDP.

However, the original Death Star took a couple of decades to build. So its annual budget is something on the order of 3x the average world’s GDP.

But how big is the Republic/Empire? There’s probably a canonical figure somewhere, but I don’t know where. So I’ll just pull a number out of my ass based on the apparent size of the Old Senate, and figure a bare minimum of 10,000 planets. That means the Death Star requires .03% of the GDP of each planet in the Republic/Empire annually. By comparison, this is the equivalent of about $5 billion per year in the current-day United States.

In other words, not only is the Death Star affordable, it’s not even a big deal. Palpatine could embezzle that kind of money without so much as waving his midichlorian-infused little pinkie. If it weren’t for the unfortunate breakdown in anti-Bothan security and the shoddy workmanship on the thermal exhaust ports, it would have been a pretty good investment, too. In other words, yes: totally worth it.”

E.D. Kain disagrees:

“In order to keep the whole intergalactic society functioning, they had to make sure they could collect revenue – after all, the decline of the Roman Empire was as much its inability to keep collecting revenue from its colonies as anything. Stretch that out over a couple million worlds and a few thousand trillion people, and the expense of governance and infrastructure quickly outweighs any Death Star budget.

Governments shouldn’t put all their resources or tax dollars into big defense systems. Not only would the Death Star almost certainly go over budget, it would also only represent a small sliver of the total Imperial defense budget. Don’t forget all those Star Destroyers and the huge cost of mobilizing troops and keeping up maintenance on all those attack droids.

The Galactic Empire made lots of mistakes. Its hyper-focus on defense spending was one of them.”

I’m going to have to side with Kevin Drum on this one — I don’t see the Death Star as anything close to prohibitively expensive. We know the Galactic Empire was a society heavily dependent on robotic labor. Given that the Death Star’s size, its builders wouldn’t have manufactured it per se. Instead, you’d just find a small, iron dense moon (there are several in our solar system that could work), and land robotic factories on it. The robots would covert a small portion of the moon’s mass into construction infrastructure, and “carve” your technological station out of the moon — all the necessary raw materials are there. This process would take decades, but given the Empire’s highly advanced robotic technology it wouldn’t be very expensive. The project’s only concrete expenses would be the initial robotic infrastructure and design expenses, both of which the Empire’s technological advances would substantially reduce.

I’m more curious about why you’d build a Death Star in the first place — unless the planet-destroying laser is nearly all of the station’s mass, why would you build it so big? We know the first Death Star had “a crew of 265,675, as well as 52,276 gunners, 607,360 troops, 30,984 stormtroopers, 42,782 ship support staff, and 180,216 pilots and support crew.” Wouldn’t it make more sense to limit the Death Star to the minimum mass required for the superweapon, and use an accompanying fleet as troop transports? After all, today’s navy doesn’t use supercarriers for every role: air defense, troop transport, surface warfare and anti-submarine defense are all performed by specialized ships.

The best rational for the Death Star’s truly massive scale would be to make it invulnerable. Neglecting the stations’ weaknesses in the films (Imperial defense contractors: “hey, do you think this two-meter wide hole that leads straight to our insanely unstable reactor will be a problem?”), it’s hard to image how to significantly damage an object with a mass of 1.08 x 1015 tonnes. Speculative science fiction weapons aside, what could blow a meaningful hole in something so big? Even an antimatter warhead would have to be prohibitively large to damage the thing. Throw a few kilometers thick ice shield over it, and you have a weapon that’s pretty close to indestructible. Once the Empire made the political decision that destroying planets was in its long-term interest, the Death Star was a sound investment.

Space Colonies Probably Won’t Happen

By Taylor Marvin

Via Web Urbanist.

Via Web Urbanist.

At The Economist’s blog Democracy in America, N.L. takes a dim view of Gingrich’s beloved moon colony:

“Money can be made without creating a lunar colony, but it seems colonisation in and of itself is Mr Gingrich’s goal. And that presents a problem. We already know that short periods of near-zero gravity are extremely unhealthy for adults. They suffer significant losses in bone density and muscle atrophy after only six months on the space station. How about a lifetime on the low-gravity moon? And what about the children?! The human developmental process is designed for Earth’s gravity, meaning a moon pregnancy would involve serious risks. Any child that survived would be crushed by gravity if they tried to return to the Earth.

At this point one could mutter something about developments in technology that could overcome basic human biology, but even humanity’s mastery of technology cannot overcome the facts. The moon is a cold, airless, lifeless lump of rock a long way away. Only a lunatic would want to raise kids there.”

Daniel Larison piles on:

“On top of that, there is no need for any of this. Setting up such a colony, besides being bad for the colonists and a massive waste of resources, would serve no real purpose except to serve as a monument to our willingness to embark on useless, costly projects.”

Scientific space exploration is important, and it’s likely that an increasingly affluent and populous world population will drive resource extraction in the inner solar system sometime this century. But living off-world is a different story, and I don’t see any motivation for leaving Earth that could offset the incredible cost and dangers of doing so:

“Humans probably will have the propulsion and robotic technologies necessary to create asteroid habitats this century, and it’s probably safe to bet on the emergence of the types of fusion propulsion systems necessary for reasonably quick travel throughout the solar system in the next two hundred years. However, living outside the familiar environment of the Earth will always be enormously expensive. Even on Mars, whose terrestrial environment is relatively similar to Earth’s and possesses the space and atmospheric pressure to permit reasonably cheap agriculture and habitation, it will always be hugely expensive to house, feed, and protect settlers. The cost on low gravity, vacuum environments like moons or asteroids will be even greater, though somewhat reduced by the ease of escaping small bodies’ gravity well. Ultimately people won’t be willing to bear these enormous costs of settling the solar system unless there is a pressing reason to do so. Science fiction writer have always assumed that the specter of an unbearably crowded Earth would be this motivation. Fortunately, this future looks unlikely. Sure, a planet inhabited by 10 billion increasingly affluent consumers will represent enormous social and environmental challenges, some that may be extremely difficult to overcome. However it is unlikely that the costs of a 10 billion strong terrestrial population will ever be enough to offset the challenges of a significant portion of the human species living off the Earth. If today’s favorable demographic forecasts hold true there simply won’t be enough humans to ever justify investment in significant off-world settlement activity.”

Of course, the off-world settler’s motivations to leave Earth don’t have to be economic. Many libertarian and like-minded groups have fantasized about establishing societies at sea, beyond the reach of government inference. It’s possible that future malcontent idealists will feel a the desire to leave Earth behind completely. But that doesn’t change the fact that even in the medium-term establishing permanent colonies in space will be enormously expensive. Modern prospective “seasteaders” have floundered due to lack of funds — there’s no reason to suspect that this constraint will be easier to overcome in the future. Ultimately space is cold, dangerous, and lonely. If the Earth remains habitable, I don’t see very many people wanting to leave it.