Posts Tagged ‘space colonization’
[LINK] “Spaced out”
Via Bruce Sterling I came across an article by Greg Klerkx at Aeon Magazine, “Spaced out”. The author takes a look at the apparent paradox that in our post-Cold War era, just as the technology necessary to support a viable manned presence in space is appearing, interest in space colonization is dropping off. He draws interesting parallels with ocean colonization.
Most of what we have learned about living in space is that we should not live in space. We are designed for gravity; without it, strange things happen to both body and mind. For each month spent in space, humans can lose up to two per cent of their bone mass. This means that each day, for hours on end, the ISS becomes the world’s highest-flying gym to keep its occupants fit. But even with such precautions, some returning space travellers require months of rehabilitation to readjust to life on Earth. Others, despite having access to the best facilities and treatments available, experience headaches, sight loss, and undiagnosed physical and psychological frailty for the rest of their lives.
But these are mere hardships, not showstoppers, and those who’ve pioneered at the edges of human experience have always managed to endure them. Physiological challenges aside, life aboard the ISS is not unlike life on a submarine or in an Antarctic research station: isolated, cramped, and relentlessly task-focused. ‘But,’ the space futurist will say, ‘who is to say these limitations are permanent?’ After all, we might one day be able to create artificial gravity, which would significantly minimise the damage done to the human body in space. We might one day be able to build, launch and populate some version of the floating paradise envisioned by Tsiolkovsky and O’Neill, giving us greenery and companionship in space — and some measure of Earthly elbow room.
‘One day’ is the sustaining trope of today’s astropreneurs, and it is mother’s milk to the clever engineers and researchers at NASA and the European Space Agency, who continue to churn out studies and CGI animations pushing, ever pushing, for a humans-in-space future. One day, anything is possible: science and science fiction, hand in hand, have conspired to make us believe this is true. One day, living in space might be as easy as living on Earth.
But will it matter to anyone? That we might be able to live in space does not mean that we still want to, or that the arguments put forward for doing so will still resonate across the cultural landscape. Indeed, a closer look at the four space stations now in orbit reveals that the living-in-space dream is, in fact, in serious trouble.
No amount of spin can mask the incredible expense of the International Space Station, which has thus far cost an estimated $150 billion to build and operate. For that price, NASA could build, launch and operate several dozen Mars Curiosity rovers. The station’s scientific value is routinely criticised as being paltry, particularly when compared with other high-end science projects such the Large Hadron Collider, which was built for about $10 billion, less than a tenth of the price of the ISS. The ISS is routinely promoted as a stellar example of cross-cultural collaboration, but it’s unclear whether the multi-national consortium that runs it will keep it operating past 2020.
[LINK] Centauri Dreams on cometary civilizations
Writing at his blog Centauri Dreams, Paul Gilster in the previous days has made three posts about the audacious possibility of colonizing the Oort cloud, drawing on earlier writers referenced in the posts. The Kuiper belt and the scattered disc, zones of the solar system stretching far beyond the orbit of Neptune, are remote enough: frigid, distant, icy. The Oort cloud, the cloud of innumerable comets orbiting our sun at a distance of sizable fractions of a light-year, are more remote yet.
The first post was “Into the Oort Cloud: A Cometary Civilization?”. Resources are available.
Embedded with rock, dust and organic molecules, comets are composed of water ice as well as frozen gases like methane, carbon dioxide, carbon monoxide, ammonia and an assortment of compounds containing nitrogen, oxygen and sulfur. Porous and undifferentiated, these bodies are malleable enough to make them interesting from the standpoint of resource extraction.
[. . .]
Put a human infrastructure out in the realm of the comets, in other words, and resource extraction should be a workable proposition. Terra talks about colonies operating in the Oort Cloud but we can also consider it, as he does, a proving ground for even deeper space technologies aimed at crossing the gulf between the stars. Either way, as permanent settlements or as way stations offering resources on millennial journeys, comets should be plentiful given that the Oort Cloud may extend half the distance to Alpha Centauri.
The second was “Life Among the Comets”. This one imagined sources of energy for these deep-space colonies, including nuclear energy but also mirror farms.
[M]irror farms are themselves components of even larger arrays, spread out perhaps 200,000 kilometers from the cometary nucleus. Growing the community would mean creating comet clusters by moving new comets into range, which would allow populations up to 100,000 or so to exist, though spread out widely through the cluster. With perhaps a light-day of separation between communities living in such clusters, the colonists would be in constant electromagnetic communication with other settlements scattered throughout the inner and outer Oort.
As wondrous a science fictional setting as this provides (and vast mirrors inevitably call to mind the continent-sized sails of Cordwainer Smith’s “The Lady Who Sailed the Soul”), I’d like to think there are more practical ways to produce the needed energy. But what? Fission doesn’t fly out here because the heavy elements are found in only minute amounts. Remember, we’re not talking about a colony world that is sustained by regular supplies from the inner system. We have to exploit local resources, and that takes us to the deuterium available in comets.
The third, “Into the Orion Arm”.
A small but growing human population in the Oort Cloud will master cometary motion, taking advantage of the fact that at 10,000 AU, the speed needed to orbit the Sun is just 300 meters per second. Compare this to the Earth’s 30,000 meters per second and it should be obvious that it takes only a small change in velocity to alter a comet’s orbit. We’ll have learned this in theory if not in practice because it factors into the engineering needed to divert a potentially dangerous comet from striking our planet decades in the future. Learn how to bump comets to change their orbits and you start thinking about what else you might do with such an object.
Interstellar space must be littered with comets that have been ejected from our system through the 4.6 billion years of its existence. Some estimates run as high as 1000 Earth masses in cometary material, so the resource base between us and the nearby stars should be plentiful. If Oort Cloud comets are separated by about 20 AU, these interstellar comets may be hundreds of thousands of AU from each other. The Oort Cloud should be in perpetual flux as some interstellar comets enter and move through it while other comets are pushed back out.
The whole idea strikes me as very implausible, given the vast distances and scarcity of resources needed to support life. Even if there are–quite plausibly–rogue worlds, dwarf planets like Pluto and even larger worlds, in the area of the Oort cloud, that still leaves vast spaces without resources. The whole area of the Oort cloud is likely to be lacking in the metals–conventional metals such as iron and copper, not just elements heavier than hydrogen–that play critical roles in industry, even if other materials are present. As for the sociology of scattered groups of dozens of people separated from realistic likelihoods of physical context, I’m confident in fearing the worst.
[LINK[ Centauri Dreams on colonizing the Kuiper Belt and beyond
A couple of posts in the past week by Centauri Dreams’ Paul Gilster have considered the question of a far-future colonization of the ice dwarfs of the Kuiper belt, the cloud of icy bodies orbiting beyond Neptune’s orbit of which Pluto is the most prominent member. Inspired by Karl Schroeder’s blog post about the distinction between habitable and colonizable worlds, and by a recent talk given by engineer Ken Roy, Gilster speculates. In “Interstellar Expansion: Colonizing Ice Dwarfs”, he sets things up.
Pluto is a case in point. Here we have a surface that appears to be a shell of nitrogen ice covering water ice. When New Horizons gets to the Pluto/Charon binary in 2015, one thing to look for is an equatorial bulge that could have been left over from the early days of Pluto’s formation. No bulge makes the case for stretching of the ice shell over Pluto’s lifetime, strengthening the possibility some are noting that the ice dwarf could contain an ocean beneath about 165 kilometers of crust, an ocean that may be just as deep as the crust is thick
[. . .]
Build a settlement on an ice dwarf in the outer system and you are not only creating space for living and doing science, but also building the technologies that will one day be used in interstellar colonization missions. But Roy noted that the science fictional image of a domed city in a harsh landscape just won’t work here. Induce Earth-class atmospheric pressure inside such a dome and even a small one (1000 feet in radius) would require a four-inch thick layer of steel to keep the dome intact. Moreover, ice dwarfs have but feeble gravity, creating medical issues from muscle atrophy to bone problems, loss of body mass, sleep disturbance and more. A better choice, then, is to move inward, creating the colony deep within the ice dwarf itself.
At 160 meters, the ceiling of a colony hollowed out within Pluto would be fully supported by the air pressure inside. Artificial light would be essential, of course, and we still have a gravity problem, for Pluto’s gravity is only 6.7 percent that of the Earth — a 200 pound person on Earth weighs but 14 pounds on Pluto. Roy suggests a rotating torus in this setting could provide living and working spaces at 1 Earth gravity. At 1 revolution per minute, a 1790-meter torus supported by maglev rails could accommodate, by Roy’s estimation, 10,000 people living in conditions that would more or less resemble the worldships so often imagined by science fiction writers.
We’re assuming technologies that can create large rotating structures in low-gravity environments, with the ability to move spacecraft at velocities of 0.001 c to build and supply the colony. We’re also assuming proven fusion power plants and considerable expertise in mining and construction. We would put these tools to work to extract local silicates and metals from the surface and, perhaps, rock from buried impactors. We would be working in an environment rich in H2O, but also in methanol, hydrogen cyanide, formaldehyde, ethanol, ethane and long-chain hydrocarbons, all within a salty ice mantle.
In “Resources Between the Stars”, Gilster concedes that these icy worlds are likely to be very poor in the metals and other heavier elements necessary for life, never mind civilization. He turns to rogue planets, too.
We know little about these worlds, but it’s assumed that great numbers of them are out there, doubtless the result of gravitational interactions in young solar systems that caused them to be ejected. Dorian Abbot and Eric Switzer (University of Chicago) call these ‘steppenwolf’ planets because they ‘exist like a lone wolf wandering over the galactic steppe.’
Louis Strigari (Stanford University) has estimated that as many as 105 objects larger than Pluto exist for every main sequence star. If that’s anywhere like the case, then rogue planets ranging between the size of Ceres and Jupiter should be out there in abundance, and we can hope to put some constraints on their numbers through future gravitational microlensing surveys and even exoplanet transit studies, which may catch a rogue planet’s transit. Some studies show that radiogenic heating from the planetary core could keep an ocean under crustal ice liquid for billions of years even out here, where there is no star to provide warmth.
Deep space is not without resources, as we’re learning every day. Roy told the audience in Huntsville that cometary objects from the Kuiper Belt to the Oort Cloud should offer CO2, ammonia, methane, oxygen, carbon and nitrogen, while we can exploit asteroids for silicates and metals. We can only imagine what resources might be available in unattached worlds moving between the stars. This is all work for a civilization that has built a thriving deep space infrastructure, but then, thinking about the future is what we do here.
[LINK] “A tale of two worlds: habitable, or colonizable?”
In a post at his blog, Canadian science fiction writer Karl Schroeder makes the distinction between “habitable” worlds and “colonizable” worlds. To illutrate, he uses two recently discovered exoplanets: Alpha Centauri Bb, a planet somewhat more massive than the Earth orbiting Alpha Centauri B in a scorching three-day orbit; and, Gliese 667Cc, a super-Earth that orbits stable red dwarf Gliese 667Cc squarely in its habitable zone. Gliese 667Cc could support liquid water on its surface, and thus conceivably an Earth-like environment. Alpha Centauri’s world, though, might be a better prospect, for all that the half of its surface permanently exposed to its sun is a magma sea. Why?
Because 581g is a super-earth, the gravity on its surface is going to be greater than Earth’s. Estimates vary, but the upper end of the range puts it at 1.7g. If you weigh 150 lbs on Earth, you’d weigh 255 lbs on 581g. This is with your current musculature; convert all your body fat to muscle and you might just be able to get around without having to use leg braces or a wheelchair. However, your cardiovascular system is going to be under a permanent strain on this world–and there’s no way to engineer your habitat to comfortably compensate.
On the other hand, Centauri Bb is about the same size as Earth. Its surface gravity is likely to be around the same. Since it’s tidally locked, half of its surface is indeed a lava hell–but the other hemisphere will be cooler, and potentially much cooler. I wouldn’t bet there’s any breathable atmosphere or open water there, but as a place to build sealed domes to live in, it’s not off the table.
Also consider that it’s easier to get stuff onto and off of the surface of Bb than the surface of a high-gravity super-earth. Add to that the very thick atmosphere that 581g is likely to have, and human subsistence on 581g–even if it’s a paradise for local life–is looking more and more awkward.
Colonizable worlds, Schroeder goes on to suggest, have accessible surfaces, elements needed for life and industry in sufficient quantity, and a “manageable flow of energy at the surface” (Venus’ surface fails as its uniformly superhot). Mars comes off badly, actually, on account of its low nitrogen content.
[REVIEW] Goldstein, Goldstein and Sternbach, Star Trek Spaceflight Chronology
Back in July 2011, after only a brief amount of hesitation I bought at BMV on Bloor West in downtown Toronto, a copy of Spaceflight Chronology, written by Stan and Fred Goldstein and illustrated by Rick Sternbach. I was really lucky: The book may have been printed back in 1980, but not only I was able to find a good copy, but I was able to find a cheap one, too! (A side note: I’d never have come across it if not for a physical bookstore where I could actually browse for books. Physical bookstores matter.) *
The Spaceflight Chronology is a good read. Between its detailed and engrossing chronology–progress always happens, people learn, technologies advance, frontiers retreat–and the very high qualty of Rick Sternbach‘s colour and sketch illustrations, both colour and sketch, I’d say it bears comparison with the classic Terran Trade Authority series.
This book is very much a product of its time, as the Spaceflight Chronology is a double alternate history. Star Trek itself is an alternate history, describing a world that is fundamentally different from our own, but more, the Spaceflight Chronology recounts a version of Star Trek radically different from the canon that has been developed since its publication. In the Spaceflight Chronology, for instance, the Eugenics Wars of the 1990s was Earth’s final conflict, following which space travel and colonization flourished along with Earth’s unification, with an aggressive blue-algae-driven terraforming of Venus succeeding by the mid-21st century even as the Moon and Mars were colonized and the first STL ships sent to Earth’ neighbours entirely independently of any other power. In the current Star Trek universe, Earth continued to struggle through its geopolitical turmoil, seeing space travel and space colonization develop at a rather slower rate than above finally suffering a global nuclear war before Cochrane’s development of warp drive led to a rather necessary Vulcan protectorate and, ultimately, to the emergence of Earth as an autonomous power in the galaxy. **
Why these differences? The Spaceflight Chronology was published at a time when all there was to Star Trek were the three seasons of the original series from the 1960s, the 22 episodes of the animated series from the early 1970s, and, just barely, the first Star Trek movie from 1979. There really wasn’t much canon at all for fans of the show. The Spaceflight Chronology ended up playing a major role in providing a broader depiction of the Star Trek universe for fans, its timeline and details inspiring both the FASA Star Trek roleplaying game and the 1980s Pocket Books novel continuity. Roddenberry began to enforce his copyright against these non-canonical perspectives on his universe in the late 1980s, stripping the RPG license from FASA, putting editors in place to make sure that the novels could never come close to challenging his writ, and–of course–producing Star Trek: The Next Generation with its own backstory. Only isolated elements from this earlier continuity have survived to the present, even in the more liberal realm of the novels. It’s still fun to read this, the fount of so much Trek.
The Spaceflight Chronology is also a sterling example of the science fiction of its time, a carefully-detailed and charted history of humanity’s expansion into the universe. Solar power satellites cheaply provide the abundant energy needed for the betterment of life on Earth; the space shuttle provides rapid and efficient access to space and is itself but the precursor multiple O’Neill cylinders occupy the LaGrange points of cislunar space while a Mars base was founded last year; Venus is successfully terraformed within a century via Sagan’s blue-green algae and imported water from comets; and, with increasing confidence, humanity reaches out to neighbouring stars and makes there not only new homes but new friends. Space travel can be easy, space colonization even easier, and the universe is a potentially warm, friendly, and comprehensible place. I really have to give props to everyone involved in this book for making it work so well.
* This review is derived from this Trekbbs.com post and subsequent discussion.
** (Being even more geekier beyond these details of the past, the near-Sol environments differ markedly. In the Spaceflight Chronology, Earth’s first contact is made at Alpha Centauri in 2048, when the UNSS Icarus happens upon the astonishingly very-nearly-human Alpha Centauran civilization, opening up a productive relationship that sees the Centauran Zefram Cochrane start a joint Earth-Centauri program leading to the development of warp drive. The discovery of a damaged Vulcan scout craft in Sol system by the UNSS Amity and the return of its crew to the Vulcan homeworld in the Epsilon Eridani system follows, with contact made in 2073 with the Tellarites and at an undetermined point with the Andorians. By the end of the 21st century, these five states and Rigel have bounded together to form the United Federation of Planets. By the time of V’Ger’s visit just after the beginning of the 23rd century, the Federation is a thriving culture set to develop rapid intergalactic travel, ubiquitous psionic skill sets in anyone so interested, and the ability to move planets about. In the actual Star Trek universe, Vulcan is in the 40 (or, if you would, Omicron 2) Eridani system, not nearby Epsilon, Alpha Centauri’s extensive planetary system was unpopulated until Earth colonists set up an independent state there some time after the mid-21st century, contact with the Tellarites and the Andorians seems to have been limited by the Vulcan protectorate well into the 22nd century, Rigel was not a founding member of the UFP, and the development of the technologies I described at the end of the last paragraph is well, well into the future.)
[LINK] Two Centauri Dreams links on Alpha Centauri Bb
There’s an odd sort of symmetry in the title of this post, isn’t there? Centauri Dreams’ Paul Gilster has good coverage of Alpha Centauri, as one might expect given the title of the blog.
At the news conference, Laughlin likened our current state to halftime at a football game. We’ve pulled out a major detection but even as we start to speculate about rocky worlds further out in the system, we’re faced with increasingly difficult observations. We can expect the Alpha Centauri story to unfold slowly, but Xavier Dumusque (Centro de Astrofísica da Universidade do Porto) pointed out how much more difficult it becomes to find planets as we move further out in the Centauri B system, adding that it would take at least twice as many measurements as the Geneva team has now made. Right now the researchers are saying the HARPS spectrograph might be limited to a planet with a lower mass limit of about four Earth masses here, but Stéphane Udry added that new ESO instrumentation was in the works that offered, in the not so distant future, good prospects for finding an Earth-mass planet in the habitable zone.
A 230-day orbit around Centauri B should put us right in the middle of the habitable zone, the place we’d most like to find a terrestrial world. Fortunately, it’s a region of orbital stability — the effects of Centauri A only become problematic as we move as much as 3 AU out from the star. Before we can find a habitable zone planet, we’ll need to confirm Centauri B b and begin to study it, which is where that useful transit could come in. The probable picture is stark — a rocky, lava-world with a surface temperature somewhere around 1500 Kelvin, surely in a tidally locked orbit. Not exactly a clement place, but the implication of other worlds in this system will urge us forward.
Voyager 1, now 17 light hours from Earth, continues to be my touchstone when asked about getting to Alpha Centauri — and in the last few days, I’ve been asked that question a lot. At 17.1 kilometers per second, Voyager 1 would need 74,000 years to reach the blistering orb we now believe to be orbiting Centauri B. Voyager 1 is not the fastest thing we’ve ever launched — New Horizons at one point in its mission was moving with greater velocity, though no longer, and the Helios II Solar probe, no longer functional, reaches about 70 kilometers per second at perihelion. But Voyager 1 will be our first craft to reach interstellar space, and it continues to be a measure of how frustratingly far even the nearest stars happen to be.
Cautionary notes are needed when a sudden burst of enthusiasm comes to these subjects, as it seems to have done with the discovery of Centauri B b. What we need to avoid, if we’ve got our eyes on long-term prospects and a sustained effort that may take centuries to succeed, is minimizing the challenges of an interstellar journey. Making it sound like a simple extension of existing interplanetary missions would create a public backlash once the real issues become clear. Better to be straightforward, to note the vast energy budget needed by an interstellar mission, the conundrum of propulsion, the breathtaking scope of the distances involved.
