If our exoplanet hunters eventually discover an Earth-class planet in the habitable zone of its star — a world, moreover, with interesting biosignatures — interest in sending a robotic probe and perhaps a human follow-up mission would be intense. In fact, I’m always surprised to get press questions whenever an interesting exoplanet is found, asking what it would take to get there. The interest is gratifying but I always find myself having to describe just how tough a challenge a robotic interstellar mission would be, much less a crewed one.
But we should keep thinking along these lines because the odds are that exoplanetary science may well uncover a truly Earth-like world long before we are in any position to make the journey. I would expect public fascination with such a discovery to be strong. Dana Andrews (Andrews Space, now retired) has been pondering these matters and recently forwarded a paper he presented at the International Astronautical Congress meeting in Toronto in early October. It’s an intriguing survey of what could be done in the near-term.
How we define ‘near-term’ is of course the key here. Is fusion near-term or not? Let’s think about this in context of the mission Andrews proposes. He’s looking at a minimum transit speed of 2 percent of the speed of light (fifty years per light year), making for transit times in the neighborhood of hundreds of years, depending on destination. A key requirement is the ability to decelerate and rendezvous with the destination planet using a magnetic sail (magsail) that can be built using high-temperature superconductors. Andrews also assumes 20-30 years of research and development before construction actually begins.
The R&D alone takes us out to, say, 2040, but there are other factors we have to look at. As Andrews also notes, we have to assume that a space-based infrastructure sufficient to begin active asteroid mining will be in place, for it would be needed to build any of the systems we can imagine to make a starship. He cites a thirty-five year timeframe for getting these needed systems operational. Some of the R&D could presumably be underway even as this infrastructure is being built, but we also have to take into account what we know about the destination. Remember, it’s the Earth-like world discovery that sets all this in motion.
The ability to detect not just biosignatures but data of the kind needed for a human mission to an Earth-class planet may take twenty years or more to develop, and I think even that is a highly conservative estimate. For naturally we’re not going to launch a mission unless we have not just a hint of a biosignature but solid data about the world to which we are committing the mission. That might mean instruments like a starshade and perhaps interferometric techniques by a flotilla of observatories to pull up information about the planet’s surface, its continents and seas, and its compatibility to Earth-like life.
I’d say that backs us off at least to the mid-2030’s just for the beginning of exoplanet analysis of the destination, after which the planet is declared suitable and mission planning can begin. What technologies, then, might be available to us to begin interstellar R&D for a specific starship mission in, say, 2045, when we may conceivably have such detailed data, aiming at a 2070 departure if all goes well? Andrews doubts that high specific impulse, low power density fusion rockets will be available within the century, if then, and thinks that antimatter, if it ever becomes viable for interstellar propulsion, will follow fusion. That leaves us with a number of interesting alternatives that the paper goes on to analyze.
An Interstellar Point of Departure
Andrews develops an interesting take on using space-based lasers, working in combination with four-grid ion thrusters using hydrogen propellant and optimized for a boost period of thirty-two days. The specific impulse is 316,000 seconds. The lasers are mounted on a small asteroid (one or two kilometers) and take advantage of a 500-meter Fresnel lens that directs their beam to a laser reflector on the spacecraft. Let me take this directly out of the paper:
An actively steered 500 m diameter Fresnel lens (risk scale 3) directs the beam to the laser reflector on the Generation Ship Spacecraft, where it is focused onto hydrogen-cooled solar panels (risk factor 1), using a light-pressure supported ¼ wave Silicon Carbide reflector (risk factor 2.5). The light conversion panels operate at thousands of volts at multiple suns (risk factor 2) to allow direct-drive of four-grid Ion thrusters using hydrogen propellant and optimized for short life (30 days) and very low weight (risk factor 3). The four-grid thrusters provide a Specific Impulse (Isp) of 316,000 seconds operating at 50,000 volts using hydrogen. The triple point liquid hydrogen propellant is stored in the habitat torus during boost (the crew rides in the landing pods for the duration of the 32 day boost period), so there is no mass for propellant tanks. After acceleration the crew warms up the insulated torus, fills it with air, and moves in.
Image: The ‘point of departure’ design with associated infrastructure. Credit: Dana Andrews.
The ‘risk factors’ mentioned above refer to a ranking of relative risk for the development of various technologies that Andrews introduces early in the paper. Low Earth Orbit tourism, for example, ranks as a risk factor of 1, with development time in 10 years. Faster than light transport ranks as a risk factor 10, with development time (if ever) of over 1000 years. Low risk factor elements within the needed time-frame include asteroid-based mining and possible colonies, gigawatt-level beamed power, thorium fluoride nuclear space power and — this is critical for everything that follows — fully closed-cycle biological life support systems.
Image: Candidate generation ship configuration. Credit: Dana Andrews.
The habitation torus is assumed to be 312 meters in radius, rotating at two revolutions per minute to provide artificial gravity for the crew. The paper assumes a crew of 250, selected to provide differing skillsets and large enough to prevent problems of inbreeding — remember, we’re talking about a generation ship. The craft uses two thorium fluoride liquid reactors to provide power, acting as breeder reactors to reprocess fuel during the mission. Andrews comments:
The challenge to the spacecraft designer is to include everything needed within the 4000 mT allocated for end of thrust… This design closes but there is very little margin. For instance, there is only 15% replacement air and only 200 kg of survival equipment per person. All generation ships here use the same basic habitat and power systems.
Image: Laser-powered ion propulsion generation ship description. Credit: Dana Andrews.
The magsail needed for deceleration takes, by Andrews’ calculations, 73 years to slow from 2 percent of c, with deployment at approximately 17000 AU from a star like the Sun, with the goal of entering orbit around the star at 3 AU, after which time the magsail can be used to maneuver within the system. Electric sails seem to work for operating inside the stellar wind, but Andrews notes that their mass scales linearly with drag, whereas a magsail’s mass scales as the square root of the drag desired. The magsail is thus the lighter option for this mission, envisioned here as a 6000 kilometer sail using high temperature superconductors, a technology the author believes will fit the proposed chronology.
The propulsion methods outlined here are what Andrews calls a “straw man point of departure (PoD) design,” with other near-term propulsion possibilities enumerated. Tomorrow I’ll take a look at these alternatives, all of them relatively low on the paper’s risk scale. The paper is Andrews, “Defining a Near-Term Interstellar Colony Ship,” presented at the IAC’s Toronto meeting and now being submitted to Acta Astronautica.
Excellent article and a real food for thought. The potential for discovery of exoplanet Earth being impulse for increased funds for space exploration shouldn’t be ignored. It would certainly be a inspiration to a part of the public.
This is what I though the minimum size of relatively low tech Interstellar
arkship would be, I have played around with such numbers and concluded
that a living space about the size and mass of Mid sized WWII aircraft carrier (28 MT) would be a reasonable size. But on the other details.
This is a high risk mission IMO for the following reasons.
1) Not much protection and redundancy against significant meteorite strike.
2) Crew must grow their own food.
3) The mission time is too long. Even at 10ly distance it’s 500 years.
There would have to be a compelling reason to accept such risks.
Columbus felt the payoff would be worth risk.
The Apollo moon landing was less risky that this mission.
In this case I don’t think the chance of success is much beyond single digits.
I think the risk of social breakdown starts to increase dramatically with the 1st generation of crew that have no parent that can remember a deceased crewmember who was alive during the launching. I think that’s a generation 6 or 7 crewmember. or about 180 years. Maybe the risk at
250 years of travel is worth it, but certainly not 500 years. 200 years takes
us to Alpha C. or one the closer uninteresting Red dwarves.
Recommendation:
1) Wait for technology to increase the launch speed to 5% C minimum
2) launch more than one mission with a partial crew to get redundancy.
3) It would better if the a portion of the crew could hibernate, that way
you could send food packets to take the place of or supplement, the farming
Reading through the article I note two first points of debate:
1-the timeframe when we will be able to detect not just biosignatures but more date(shapes of continents, seas, first images even if just pixels), 2030-2040 seems reasonable, but I can’t but wonder how a FOCAL mission or Hypertelescope swarms would change our understanding of the universe with potential images of hundreds of exoplanets)
2-Based on the above, a generation ship is a tough animal to take on as an idea. Modern humanity has problems with determinist undertakings like this, and I fear that there would be a backlash against anything that would potentially force offspring into life of hardship and lack of choice. I think the pressure would be rather on increasing the speed for a two-generational system(with travel time of around 50-70 years to nearby planet making it possible for some members of first generation to survive the journey) or making more faster robotic autonomous probes(for the kind of astronomic discoveries we will certainly need already advanced software and robotic space telescopes capable of working independent from direct human control).
Of course another potential factor would be increasing human longevity or breakthrough in hibernation.
But a generation ship created by current model of democratic state seems unlikely. The ethical questions of course would be overcome by autocratic or religious state entities.
There’s so much to like in this concept! The use of sails for breaking, since that doesn’t use reaction mass (avoiding huge initial mass for carrying breaking reaction mass). And use of beamed power for acceleration, avoiding speculative and heavy on-board powerplants. Also, I’ve always thought that optimal (in cost sense) beamed power solution most probably uses at least some reaction mass, not just reflecting off all the precious energy and relying on light sailing. Pure lightsail necessitates not just huge available beam power, but also huge focusing infrastructure (the Fresnell lens), since low impulse of pure light means low acceleration, which means that beam must be available for longer time and thus be kept focused further away.
And if you’re in process of sending people, it’s much less of a speculation to send them alive, since any sleeper concept at 2% of c would need to handle hundreds of years worth of accumulated radiation damage once waking the sleepers at end of the trip (if freezing turns out to be possible at all).
I think this is as modest and no-nonsense sketch of interstellar colonization plan as they get. I like it a lot.
I’m having problems following this. He has a mass ratio of 6020 and an exhaust velocity of 3097 km/s, which should give a cruise speed of 26,950 km/s = 0.09 c rather than the 0.02 c you state.
He has a ship mass of 4000 tonnes for 250 people, which is 16 tonnes/person. This is only a quarter of the mass allowance per person on the ISS, but the ISS is not remotely capable of supporting its crew without constant resupply, or of supporting the raising of families over multiple generations.
If a 2070 departure is being aimed at, how many generations will have been raised in space by then? Will there really be sufficient of an experience base to commit to an interstellar flight?
Stephen
Oxford, UK
This vehicle is about 10x Boeing 747’s, and has to house 250 crew. The actual living volume is about 150 m^3 per crew, or about 750 sqft. So it is like living in an apartment for your whole life (more like a very small apartment with common space).
I cannot understand the mass ratio (~ 6000) if the Isp (316,000 s) implies an exhaust velocity of approximately 1% c and the final cruise velocity is 2% c (6000 km/s). Shouldn’t it be of the order of just 7.5x, IOW the LH2 propellant for the ion engines needs to be ~30,000 mT? I must be missing something pretty substantial.
While I don’t buy such a ship by the mid-late C21st, what about a Cassini sized vehicle at 1/1000th the mass to survey the target world, land on it and send back the data? Is that feasible with the the resources we could muster?
Astronist writes:
I pushed the timeframe hard to get to 2070 — Andrews doesn’t specify such a date. But yes, I think 2070 is far too optimistic — it’s just the earliest date I could conceive of to launch this. Trying to come up with a lower limit for ‘near-term.’
There is some similarity to what you are proposing here to our concept. We however feel the optical pump energy is not required and adds an expense and complexity not required especially for a mission headed out of the solar system.
Further, our ship design is such that we can accommodate the inhabitants during acceleration without moving them from their home. If funding were to begin today, our ship would be completed in 25 years.
Interesting article. I think the main problem is the 500 year transit time. Its too long to be socially and politically viable to decision makers on Earth. What do I mean by that? Basically, space activities – whether robotic or crewed – must occur within a political space, where decisions on whether to commit to a mission to a particular destination are determined not just by scientific interest or technological capability, but also by political interest (itself determined by popular interest) – which then determines economic viability. This particular aspect of space travel is not just relevant to future interstellar missions but is active here and now (i.e. the current debate on do we go to Mars, do we go back to the Moon, do we ‘capture an asteroid’). The nature of politics and politicians is that they are humans who have short-term narrow self-interest and certainly short-term vision – measured not in centuries and rarely in decades, but more commonly in years, to the next electoral cycle. Rarely do such people have ‘big vision’. The focus is on ‘what’s in it for me, or my political party or my national interest’, rather than ‘what’s possible for the benefit of humanity’. Cynical I know – but that’s how I read modern politics.
The politicians also think in terms economics – the money matters. If they are going to spend hundreds of billions of dollars on an interstellar mission that will then take 500 years to see any ‘payback’ on that investment, the money has to come from somewhere. Does the political leader make cuts in social welfare? Health? Education? Defence? How does that then effect his or her chances for re-election? The pie is only so big, and there is no limitless piggy bank to fund discretionary spending like space travel, be it to the Moon, to Mars or to Alpha Centauri.
So if indeed we do find a Earth like habitable planet orbiting a nearby star – lets say in the next ten to twenty years – and I believe we will – any planned mission to it has to be politically supportable and economically viable. That simply won’t happen if scientists and engineers tell political leaders “It will take us 500 years to reach this destination, but only after decades, or maybe a century, of preparation within our own solar system, creating massive infrastructure that will cost hundreds of billions of dollars”. Their response will be “Where is the political benefit to government?”. Some may even be so cynical as to say “Where is the political benefit to me?” (They of course, will be dead and buried by the time the ship gets to its destination). They will certainly say “where does the money come from?” It is political leaders who control the money, and therefore, determine where we go and when we go, and how is it all paid for. They would want their ‘pay-off’ soon – so a 500 year mission won’t fly. This is especially the case with a robotic mission – no ‘flags and footprints’ means they can’t leave their mark on human history in the way that JFK did with Apollo.
I enjoy reading Centauri Dreams, but too often the focus is on the technical and engineering aspects of interstellar flight, whilst the human aspect (in terms of practical political and economic realities) is ignored. You have to recognise these factors play a big impact.
I personally feel that such long transit times, whilst I accept are based on a solid understanding of engineering and scientific limitations at the moment, are not practical as a basis for interstellar flight because of these very reasons. At the very least the international scientific community should be investing time, knowledge, and money into developing much faster transit times to nearby stars, whilst keeping within the bounds of known principles of physics. That means decades – or better yet – years – not centuries. That means propulsion which can accelerate a vehicle much closer to the speed of light. Maybe ‘magsails’ can’t do that – so find a technology that can, and invest money, time and effort in developing that. Because it would be a terrible shame to spend decades developing a technology that does the job from a purely engineering perspective, but is unacceptable from a political perspective. The money has to come from somewhere, and politicians control the money – so they are the people whose support you must first get. If you start talking 500 years, very few political leaders would give you the time of day.
Secondly the risk is we could waste decades and billions of dollars, developing magsails, or other slow interstellar propulsion systems, only for it to be made obsolete over night by some sort of breakthrough in propulsion. Its the classical risk that we dispatch a ‘space ark’ that will take a thousand years to get to its destination, and at some point, other faster ships race past it, and by the time the generation ship arrives, human colonies have already been established. Obviously for some in the interstellar travel community that scenario does not pose a problem, but maybe rather than spending time and money on space arks, it would be better to develop the faster ships first?
I accept, we must stick within the currently understood limits of physics – sadly, no warp drive, no wormholes, no hyperspace. So we should be challenging ourselves to focus on what can we do within those limits, to get a ship (robotic or crewed) to somewhere like Alpha Centauri, or Tau Ceti within ‘decades’, and still achieve a departure date of the 2070s-80s! That to me should be the goal of the interstellar spaceflight community for the coming years. There are others on this group more informed on the engineering and the science to determine whether such a goal is practical, so I’d enjoy hearing their perspectives. But for me, being a specialist in international relations and strategic studies, I know the political mind. No matter how worthy the scientific goal, or viable a technology, it must be acceptable to political leaders and financiers, or it simply won’t happen.
Dr. Malcolm Davis
Bond University, QLD,
Australia
Malcolm Davis, There are ways around your issues … remove the politics and economics and develop a society that lives for the prospect of pioneering. This is the premise of our space habitat/colonial project.
While it is quite likely that the residents of our first orbital habitat choose not to “explore” we are not limited to the construction of one. Because of our cooperative structure, the more people are interested the more habitats we can build. Also, we are not limited to MY lifetime. While it is my vision that founded this project, it is the membership that will guide it through centuries, outside of global politics/economy.
Can this happen in a lifetime? We believe that if our funding were to begin today (minimum of 1000 members), we could house 1 million families in outer space within 25 years.
I suspect that the biggest issues to be faced by such a mission will be physiological/sociological rather than technological. Certainly, there are huge physical risks, such as mitigating ultra-high energy radiation events (rather than the background radiation environment), however, I suspect that a crew of 250 is a fraction of the number required for success, which I’d put at beyond 10,000 or even 100,000. A mission might commence with 250 highly gifted, multi-talented crew members but after even just a few generations, much of that capability will likely be lost. A big question is what following generations are told about Earth. They will have been condemned to lives without either the goal or the departure point in sight, a maddening existence. At some point, someone will say ‘not for me’, will have the capability of destroying the mission and quite likely will. The environment aboard will need to provide these generations a demonstrably far better existence than the one they would have enjoyed on Earth or we will have acted out of the utmost selfishness in sending the mission out there. (Noted, comments by Wojciech J., RobFlores, others?)
@ Dr Malcolm Davis
One of the hurdles that is currently being overcome is the notion that interstellar travel is simply impossible. The technical and engineering focus is aimed, I think, at overcoming that particular hurdle.
On the political and financial level, initiatives like the 100 Year Star Ship organisation are underway to address the outreach needed in various sectors and to foster a cultural environment supportive to this goal.
With regard to this site, many of the articles have focused on the existential risk and the role in space-based infrastructure and interstellar travel as means of addressing this risk. It is indeed unfortunate that the political and financial principles in the world do not and, it seems, cannot address existential risk but instead pursue policies that only exacerbate those conditions.
Some have even proposed that the precursors for interstellar travel will be those who are outcast or marginalised by mainstream society, much as the pirates, pilgrims of the westward expansion, or even the Polynesian seafarers who ventured forth across the Pacific. This discussion has assumes a space faring civilisation extending beyond the confines of the inner system where independent groups might find the means to slowly expand humanities footprint without the centralised authority of earth based governments and corporations.
Bad as politicians can be, they have longer-term visions than financiers do, who mostly seem to look at what they can get in the next three months.
That said, there are good reasons why few people consider projects that will only bear fruit in hundreds of years: based on history, there is little chance that we can figure out what will be useful to our descendants that far in the future. 500 years ago Henry VIII was king of England. While there are no doubt things from that time that are still of interest to us, it was a chance matter which things they were. There was no way people of that time could have guessed. Instead they did what we should do — focused on things that would be of foreseeable benefit to themselves, while leaving a rich heritage for their descendants (us) to work from.
I don’t think we need to find an Earth-like planet to launch a robotic probe. Probably the first probe will be launched to Alpha Centauri Bb, if that planet is confirmed. Also, I think that probably the first evidence of ET life will not be in an Earth-like planet (non Earth-like planets are nearer and thus easier to investigate).
Thanks for your comments all. I too share your desire to reach to the stars, not only for exploration, but also for the greater goal of ensuring the long-term survival of the human race aeons into the future. So my original post was certainly not meant to dismiss out of hand the notion of near-term interstellar flight. But I’m a political realist, and for the moment, and I think, the foreseeable future, it is the nation-state that must ultimately take the lead on deciding where humanity prioritises its focus on such endeavours. I think the commercialisation of space is an important development that could gradually eat away at the power of the state to control access to space, but this will take money, and lots of it, as well as vision and time. We need many more Space X’s and more Elon Musks out there. The alternative I think is to let government run the show, and you end up going nowhere fast – just see the stagnation of NASA. The old saying from the Mercury project days is apt – “no bucks, no Buck Rogers”. When we are talking about interstellar flight, its even more critical to get funding and lots of it.
That’s why I simply don’t believe political leaders and bankers will buy into slow interstellar travel. Talk starships and they imagine the USS Enterprise. We can’t do that yet – we don’t know how, and we don’t even know if super-luminal is even possible, given our limited understanding of physics. But we should be aiming to get there as fast as is possible with the technology of the day, because 500 year journeys just won’t get the broad political support. I even think that popular support may be lacking – some of the comments here about the social challenges of generation ships are well taken.
So we need to go as fast as we can. That may mean changing investment priorities in terms of where money goes for developing all the systems and requirements to send a ship – robotic or crewed – to a nearby star within decades – or better yet, years. Easier said than done, I know, given the huge energy it takes to accelerate even up to a small fraction of ‘c’. But if one day we want to go, I think that’s the only way we can go any time in the next 100 years. Its a physics and an engineering problem that should be solved as a first priority. We should not be investing precious time and money on slow technology that will never fly politically.
I also take the point above about an educational process for making people understand that interstellar flight is possible – and that is really important. And we do have to educate people to realise it’s not ‘Star Trek’ we are talking about. Louis…as for ‘removing the politics and economics’, I’m dubious about that idea. There has NEVER been a human civilisation without politics of some sort, from ancient tribes with leadership hierarchies through to modern democracies. Even so called ‘dictatorships of the proletariat’ – communist states – had the politics in the form of authoritarian dictatorships to impose its will on its citizens. If that is what is being suggested, then that’s hardly an ideal way to explore the universe. Utopian visions of such societies sound great, but I’m yet to see one exist. Prove to me it can work, and I’ll listen a bit more. Someone has to lead.
My broader point regarding this excellent site is that the technical discussions – fascinating as they are – need to be made against a broader human context, which must include the politics and economics. Or its just technical talk that won’t have a big impact where it must to make our visions reality. We need to be able to answer the questions “why should we go?”, and “how does going benefit society” – both to the general population and to the political and economic leaders who make the decisions. Scientific curiosity is not enough. Survival is – but Colonisation is also a vastly more ambitious goal than simply exploration.
That brings me to one final point before I close off from my hotel in Tokyo. I’ve read a lot of talk on here about sending ships not with humans on board, but with genetic material and somehow reproducing humans at the other end, to reduce complexity. The ships can be tiny, and somehow this makes it easier to get there, and cheaper. I understand the engineering vision, though I don’t understand how you ‘replicate’ and ‘hatch’ a human at the other end that is ‘me’. But my point is this – in terms of how we sell that to our political leaders, will be even more challenging, because ‘we’ are not going. I think interstellar flight must see human beings in corporeal form on the ship, and going to a star system, and getting there in years or decades, for it to be real in the eyes of most people and to capture the imagination, and thus support, of political and economic supporters. Call me old fashioned, but I think the average person in the street won’t support massive funding being directed to send genetic material to another star system, because they won’t see that as really being true interstellar exploration. They get left behind. I get the principle, but I don’t think many will.
To me, the important part here is the groundwork laid by telescopes and the expansion of human knowledge. At this point, do we really have a place to go to that’s worth the effort? I mean, there are plenty of planets/moons here in our solar system that uninhabitable or marginally habitable with enough work. I think it would take something like an earth clone for humans to go interstellar in the next century. Either it would have life and therefore would represent an incredible trove of discovery or it would be free from life but much closer to Earth than Mars. Otherwise, robotic missions are the way to go.
After reading articles here for a few years, I feel like we either need to focus on getting closer to at least 10% of c or on “exploring” the universe at light speed with new and advanced telescopes. I do love reading about work like this. It’s important speculative work that needs to be done and I appreciate every bit of it. But I wonder, if we really got someone excited enough to spend the amount of resources needed for a project like this, couldn’t we overcome some of the basic engineering challenges around getting the ship to go faster? Some really brilliant people have tackled the problems of interstellar travel, but I don’t think we’ve had the kind of funded and dedicated effort that is needed yet.
Actually (as some have mentioned before I am sure) the one of the best course of action to speed up the R&D and increase the Will to send a manned interstellar mission, is to build telescopes that enable us to image Earth Like Worlds. Once Continents & Oceans are imaged on a world with a G or K class star, the public will become enthralled.
Once we have a target that is compelling and reasonably close it will give tremendous impetus to a interstellar venture.
And as an additional primer , The public will want a mission that will arrive in their lifetime. (lets be generous and say that is about 70-80 years) that means a ship with a speed closer to 30% C. If the journey is beyond any beamed propulsion designs, anti-matter propulsion will be the ticket.
Now of course that means It may not launch within our lifetime but I would be nice to know at least that humanity is determined to travel to a ‘the next adventure’ and are working to such an end. Knowing a twin Earth is
out there assures it.
I truly liked the approach of Mr. Andrews. Simple, near term and focused. Goal driven engineering.
This is a fascinating “PoD” interstellar colony ship design… I must to read the full paper sometime soon for all the details. It is sobering, though, to see just how much of the basic technology needed for slow generation ship missions remains to be developed.
Particularly critical are the biological and sociological aspects of such trips- optimal crew size, social dynamics, and how exactly to keep them alive and healthy for many generations. The last requirement is subsumed in the phrase “closed cycle life support system”… easy to say, but perhaps not as easy to engineer and keep functioning for centuries!!
Dana Andrew’s take on the beamed energy rocket is quite interesting. One thing is clear- while nuclear propulsion might do the trick for an interstellar journey, it isn’t the only option we have for propulsion. Gregory Matloff’s solar sail concepts are another possibility (albeit a slow one!). Ion drives energized by remote lasers are another.
There are some interesting comments here as well. Malcom Davis makes a good point- we must keep in mind that starflight’s “curb appeal” can matter just as much as any engineering problem in obtaining long-term support from financiers and policymakers. Unfortunately, we do not currently live in a society that encourages long-term planning, or indeed thinking much beyond the next election cycle. A generation ship falls neatly in the category of long-term thinking (emphasis on looong).
Faster transit times would be nice, but we must play in the real of real mechanics barring any extraordinary development in wormhole physics or something (don’t hold your breath). Explaining the differences between fantasy starflight and real astronautics should be a core part of education and public outreach efforts concerning interstellar travel.
The cynic in me will point out here that one can find members of parliaments or congresses falling for such things as banning dihydrogen monoxide, attempts at explaining the finer points of astronautics seem quite hopeless…
@Malcolm Davis – Sending out genome clones will obviously not be teh equivalent of sending “me”. If it can be done, it would be purely for colonization purposes, equivalent to sending your unborn children.
Without some new physics, I am highly skeptical that humans (as we are currently constructed) will “slow boat” to the stars. The “closed loop” life support would have to be incredibly closed as a design. Even the Earth’s biosphere, good as it is, isn’t perfect.
I still think that for “instant” star travel, from the perception of the traveler, the best bet is to send a slow machine to the target star, then beam your mind to the ship for instantiation into an artificial body. Total elapsed time will be dependent on distance, although for the nearer stars, you could return and talk to your original body (and possibly directly transfer memories). IOW, we need to stop thinking like C19th humans who had to move their meat bodies to places, and think of analogs to how we use communications technology to “experience” distant locations.
Just a clarification, but Dana’s figures are wrong for the propellant – I think he slipped a few decimal places in his figures. The mass ratio should be 7, not +6,000. The power figures don’t seem to be optimised either, perhaps due to the focal distances of the optics. Would be nice to see an amended version of the paper.
The development time-scales seem reasonably conservative. One point that needs mentioning is that any development of any of those technologies would be enablers for colonising this Solar System, thus providing a more immediate payoff.
The mag sail system proposed by Jordin Kare http://www.niac.usra.edu/files/studies/final_report/597Kare.pdf seems to solve many of the problems mentioned in the comments above and promises much shorter transit times. The Andrews proposal also requires a mag sail but also adds the problems associated with using beamed power at long distances. The Mag Sail concept uses small light sails accelerated by laser to transfer momentum without the need of a large focussing system which must be quite a bit larger than the 500m lens Andrews proposes if the acceleration is to continue long enough to get to the 30% c or better that mag sails can. The small sails are ionized as they approach the starship and impart their momentum to its magnetic field.
@Adam – I think it happens the other way around. You create extravagant projects based on existing infrastructure, excess wealth and chance circumstances. Infrastructure gets built for economic reasons – there has to be a good profit argument to do it. So, the Solar System won’t get colonized, unless there is profit. No reasons to fool ourselves otherwise. Another point this paper makes abundantly clear, is that system-wide space infrastructure is a prerequisite for starflight activity of any kind.
It seems obvious to me that governments will not get involved in starflight. A positive attitude would be to consider starflight as a future activity, similar to sailboating today. Sailboating is an extremely slow and expensive way to get from one place where one has no business, to another, where one also has no business. Governments do not support it, nevertheless, an extremely low number of people (compared to the total population) have the resources to practice it. I hope, in the future, based on infrastructure, built for completely different reasons, a number of entities will have the requisite resources to do something affordable, as the generation ship, proposed in said paper.
Peter Popov,
I don’t disagree. Tell me how the technologies needed by Dana’s designs would not be useful in colonising the Solar System? CELSS, thorium power, beamed energy – all are useful.
@ Alex Tolley,
Re your point about 19th Century humans – I think my response will be “I like my meat body” and I’d argue 99% of humans would say the same. There are all sorts of potential disasters waiting to happen in terms of ‘beaming consciousness a distance of light years’. How do we do that, for starters, when we are yet to even get a 100% stable, safe and secure internet here on Earth? Even 100 years hence, and I doubt people will trust technology that much. Then there is the potential mishaps which could occur. How do we know someone’s consciousness – assuming we can beam it – will not be scrambled or lost along the way as a result of the interaction of natural phenomenon? Does the consciousness that ends up in a robot end up wrong? Is it the same ‘me’ that started? Or is it something or someone else? Then there is the more philosophical or even metaphysical question. Does a beamed consciousness contain someone’s soul? From a scientific standpoint, a ‘soul’ is impossible to observe or quantify and therefore verify its existence. But from the perspective of most of humanity, where spiritual or religious belief matters greatly, the existence of a soul is important. Until we can resolve that particular spiritual dilemma, I would argue that for most humans, having their consciousness ripped from them to transfer into artificial bodies is akin to a death sentence – and that takes me back to my initial response – ‘no’ I’d not be agreeable to that.
Finally, I disagree with the notion that the desire for humans to physically go to another star system is somehow archaic. Humans are explorers and always have been, and I don’t think that many humans will be content to merely see genetic material or uploaded consciousness or androids take away their chance to voyage to new worlds. They will WANT TO GO. If the technology is there to take them and the opportunity presented, they will want to go physically because anything else means they see it as ‘something else’ taking their place.
This is all about philosophy, perception, and personal belief – its not about engineering or science. I think that the engineering and the science is very important and vital as an enabler, but at the end of the day, its the human experience of interstellar flight that is far more important. For those going on a ship to Tau Ceti, and for the societies they leave behind who understand that humanity has become a true interstellar spacefaring civilisation, that is a far more important achievement than sending robots, even if we could upload them with some sort of consciousness. That human factor is missing with robots, or ‘hatched humans’ who maybe have no perception or awareness of their origins, and we simply don’t know whether the robots are us because machines are not humans. Preserving my physical existence and wanting to go in person may seem a quaint, 19th Century perspective, but I’d argue its ‘reality’ and its how human beings function, and they will demand to go in person. We can’t change what it means to be human just because its technologically more convenient to impose some other way of travel that denies humans the freedom and opportunity explore new worlds and build new societies.
So, if we are to travel to other stars, we have to do it ourselves, in ships we build that are designed to get us there in a reasonable period of time – years or maybe decades at the most. Maybe suspended animation can ease some of the challenges, but I think generation ships generate too many social risks and problems. Fast starships – not superluminal – but high relativistic speeds – must be the goal. Thats challenging technologically and in an engineering sense – and probably demands more exotic propulsion like anti-matter/matter fusion – but its the best way. That should be our goal.
Peter Popov
“Governments do not support it, nevertheless, an extremely low number of people (compared to the total population) have the resources to practice it. ”
Some governments motivated by religion or ideology might do it.In the past I posted to organizations of religious nature that might be tempted to pursue interstellar colonization as well.
So there is a small chance for this, however overall I believe such slow generation ships to be unlikely as well.
Malcolm Davis said on October 9, 2014 at 23:33:
“Re your point about 19th Century humans – I think my response will be “I like my meat body” and I’d argue 99% of humans would say the same.”
Humans only like being in a physical body because they don’t know any other kind of storage for their minds yet. If they could upload or transplant their brains into a supertough, long-lasting robot body with a computer system that allowed them to think faster, better, and with amazing memory capacity, how many would turn that down?
Look at how popular all those exercise, diet, and makeup products are, to say nothing of plastic surgery. Most people do not care to remain as nature made them, and those that do spend a lot of time, energy, money, and resources on maintaining what society perceives as a wonderful body.
When humans can change their looks and abilities, they will do so in droves. The “normals” will become the odd ones out.
Enhanced humans will probably make much better interstellar voyagers anyway. It is rather foolish to assume that by the time a Worldship might be ready to launch that humans will be in the same state they are now. They might also opt to send avatars of themselves to explore the Final Frontier while staying back in the Sol system.
Governments are more likely to cause it to happen by giving people reason to want to escape them, frankly.
We’ll colonize the inner solar system, this will give us the tech to colonize the outer solar system, and then people will start colonizing comets on their way out of the inner solar system, and then somebody will throw a nuclear rocket on their comet, and just keep going.
Honestly, there ARE no near term prospects for interstellar travel. Though it does make for fun mental exercises.
There may be reasons the crew cannot be shrunk to, say, a dozen, but this is not one of them. Inbreeding can and will be taken care of by taking frozen sperm and eggs. Easily, with currently routine technology.
Malcolm Davis:
You might have said something like this 75 years ago about people trusting their frail bodies to oversized winged tincans criss-crossing the Earth at nearly the speed of sound, 40,000 feet above ground.
:-)
Besides, most reasonable concepts of “beaming consciousness” do not anticipate the original to be destroyed in the process, necessarily. So you can stay on Earth and go to Alpha Centauri, both. Seems like a win-win to me, even if there is a high risk the traveling version will not make it.
@ ljk – not denying advances in medical technology, IT and robotics might make closer human-machine interaction or integration possible. I think that is quite likely. But the idea of transferring a consciousness remains speculation. How do we define what a consciousness actually is? Until we know exactly what it is, where it is, and how to access it, completely without destroying any aspect of it in some transfer process, ‘uploading’ remains science fiction. And I do think you are reading too much into human attitudes towards personal improvement. This not just looking better or being fitter – such aspects are trivial compared to what you and others are suggesting.
Absolutely, if the artificial bodies are indistinguishable from traditional human bodies, and if the consciousness is understood completely and can be transferred without error, guaranteed 100% every time, and if we can resolve the metaphysical mystery of the human soul (if it exists), then you are right – people would leap at the chance to live forever in perfect, indestructible bodies. I probably would too.. But those are a lot of very big IFs to get past. If the artificial bodies are clearly ‘artificial’ – machines – then most humans would I think baulk at the prospect of living in what they would rightly be perceived as a metal prison. I also do think you can’t get past the fear of losing something of ourselves in a transfer process, so that what ends up in the artificial body is not us, but a fake, imperfect copy of us. How do you convince people they will be them at the end of the process? But I want to emphasise that even though I’m dubious of this idea, I’m willing to keep an open mind and be convinced, if the technology can be proven. Trouble is, that probably won’t happen in my lifetime.
I think at age 50, I doubt I’ll see this, unless some pretty radical advances are made – the very thing you are talking about, or something along the lines of biotech and genetic engineering to extend human life. So I hope you are right – but I suspect uploading will be hard to perfect, meet a lot of moral and ethical opposition, not to mention fear from people who will have to balance the dream of living forever, with the potential nightmare of living forever trapped in an artificial body, with aspects of themselves lost in the process. The spiritual dilemma is a big one – can you imagine how religion will react if we can literally make death obsolete? That challenges some of the most basic aspects of organised religion and the role of God. Whilst I try to examine these issues from a scientific basis, and firmly believe that science offers many of the answers, I also have my own beliefs in terms of religion, and I can see the dilemma between science and religion being really sharpened by this question. Then there is the social dilemma – who gets to be uploaded? Is it everyone, or only those in the social and economic elites? This issue cuts across so many issues and is much bigger than just its application to interstellar travel, and it has huge potential for generating social and societal disruption and division.
It might be easier just to build faster starships…
@Malcolm Davis
Unfortunately we don’t seem to have any way to do that with any proposed technology. In addition, the energy requirements are enormous, which is why so many favor “slow boats”.
You are absolutely correct that we have no mind uploading technology, but we are working on do that in a sense by non-destructive imaging. As long as you are not adhering to a discredited dualist version of brain and mind, this should, in principle, allow mind transfer. There are many good SF books that explore the consequences. e.g. Robert Sawyer’s “Mindscan”. As for humans and better bodies, there is a pretty awful movie “Surrogates” that has this as the underlying premise. We are rapidly advancing the technology to provide electronic senses, especially the sense of touch, that will be able to give us technology that mimics the human body and will not feel like being stuck in a dead metal shell. But again, some people may prefer the metal shell, especially if if gives them the freedom to do other things.
Any religious objections are irrelevant. Either you will be part of the post-human, off planet civilization, or you won’t. Post-humans will have very different “religions”.
Finally, if a mind transferred human gets to the stars well before any real humans, because that approach was far quicker to implement, humans will find themselves the late comers, possibly highly disadvantaged. Big ships hauling meat may seem as quaint as barges when we are ready to travel interstellar, rather than intra-solar system distances.
Malcolm Davis:
I think you are setting some unnecessarily high standards, here. As many a concussion, stroke, or brain injury victim can tell you, souls (whatever they are) can accomodate losing a substantial percentage of their underlying substance, without losing their identity or personality.
And there are plenty of things, especially in medicine, that are not understood completely, and yet are applied routinely, with great benefit. Think about psychotropics, for just one example.
Malcolm Davis October 10, 2014 at 22:28
“If the artificial bodies are clearly ‘artificial’ – machines – then most humans would I think baulk at the prospect of living in what they would rightly be perceived as a metal prison.”
Is a “meat prison” any more pleasant to many people, especially those who suffer from serious physical ailments while their minds remain intact. If we do develop artificial bodies that can embody a human mind, I would like to think things might be advanced enough that you could also have a body that looks and feels like our current meat sacks, but tailor made.
As for your comments on religion, the smarts ones will adapt and adjust to the times. Perhaps those who refuse to change will be allowed to live on specially reserved areas so they can carry on with their beliefs, so long as they do not pose a threat to others who do not share their views. If we can get off our duffs and start colonizing the Sol system there should be enough room and resources for everyone to live as they want.
Alex, (updated)
When you said “Any religious objections are irrelevant. Either you will be part of the post-human, off planet civilization, or you won’t. Post-humans will have very different “religions”., please no disrespect to you personally, but I was struck how arrogant that sounded. Most of the human race has some form of religious belief that is important to them, and I myself am a Christian. It’s important to me, even though I also am a strong believer in Science as the best way of understanding the universe around us. I’m certainly not a dogmatic Christian fundamentalist, and I’d disagree with quite a few teachings of Christianity that I see which conflict with clear scientific evidence to the contrary (e.g. Creationism is an obvious myth). But I don’t see the need for one belief to cancel the other out completely. My problem is that your comment in effect dismisses my belief not because you can prove its wrong (nor can I prove mine is right either, I accept) but because you feel it has no place in the future you are painting. Yet, in making that judgement, are you then denying human beings who do have a religious faith the right to the same opportunities – to travel to the stars – as those who adhere to post-human ideals and aspirations? I’d argue that 200, 300 years from now, when we are talking about this happening, there will still be Christians, Jews, Muslims, Hindus, Buddhists, and others, who will want to go. To say they must give up their beliefs to be part of humanity’s next great adventure is pretty cold and smacks of discrimination. Is that the future you propose?
If it is, then I think we agree to disagree on this, and I think that there has to be a better way, even if it demands a more technologically demanding solution of faster starships than can take real people to nearby stars in something under thirty years. I think people of all faiths and beliefs should be allowed to go to other worlds – not just post-humans – and humans should not be forced to give up their faith to do so. Humans should not be divided into those who are post-human and those who are not. Too much of human history has been a bloody affair because of divisions being imposed on societies from above because of race, religion, ethnicity, or personal belief.
Let me conclude by saying that no one should stop humans who want to be post-human, and upload their consciousness into a machine from doing so. Humans don’t have the right to deny that choice, just as post-humans should not deny humans the chance to experience physically going to other worlds based on their religious beliefs. What I’m saying is that this is a philosophical and ethical and moral dilemma that is yet to be really confronted, if indeed technology is pointing towards the eventual emergence of post-humans. I think most of humanity have not even heard of the term ‘post-human’ let alone understand what it really means. I think that we are struggling right now as a species to deal with the complexities of race relations, gender equality, religious tolerance, and respecting sexual preferences. Look at how much tension these issues is creating now….can you imagine how humans might react once the post-human question comes to the fore? Can you then imagine if the post-humans start to arbitrarily constrain the freedoms and rights of humans? Your sentence quoted above suggests all the worst for a future divided society.
Eniac
Re your points about air travel versus beaming consciousness, I think its a good one. In 1902 people were still saying powered human heavier than air flight was impossible, and I’m not saying beaming human consciousness into an artificial body is impossible – I’m arguing its probably going to be exceedingly difficult, and working on the mathematics and physics of aerodynamics would be easier in comparison. Until we know what ‘consciousness’ is – how to define it, identify it, store it, and send it – its process fraught with risk to the sender (is the consciousness being copied or simply uploaded – if its the latter, what happens to the original person’s mind, memory, etc), and also to the ‘life form’ on the other end. What about their rights? Is it okay to create some vegetables in a trial and error process who then have to live out their lives because the upload did not fully work? Or are they euthanised? If they are an artificial human – a machine – but with an uploaded human consciousness, are they alive? If they are alive, are they sentient? If they are living sentient life forms, then they have rights too. So you can’t flick the off switch if the process goes wrong. You are talking technology – I’m talking ethics. I have no problem with the technology – I do have a problem with the potential ethics issue. We have the same concerns over human cloning for example, which is why we don’t do it. Its why I am setting unnecessarily high standards, because anything less and we risk creating some very serious ethical and moral traps. Then there is the religious issue of the soul – which Alex and I have debated a bit, and I think I make my point there.
So my bottom line is that all these moral, ethical, religious and social dilemmas can be avoided if we invest the time, knowledge, technology and money into building fast starships – and also in the process ensuring the political and economic support for interstellar travel can be maintained. I know getting a ship to fly closer to the speed of light is much more challenging than either a generation ship (which has its own unique problems), or the whole post-human ‘uploading’ approach (which generates immense risks in my view). Maybe it is just too demanding technologically to get a ship to travel fast enough to get to Alpha Centauri in say 20 or 30 years. In which case, we are then confronted with the other choices, unless someone can find a way to circumvent Einstein – and like most other people on this site, I agree we have to assume that won’t happen, and plan on that basis.
You don’t have to be dualist to be skeptical of mind/consciousness transfer. It’s entirely possible (in fact I think likely) that our individual consciousness is a product of our particular physical brain and can’t be transferred other than by something like a brain transplant. Even an apparently exact brain replica might merely generate a new consciousness of its own rather than the “same” consciousness as the original. How would you verify what was happening? The replica might believe (based on memory) that it was a continuation of the original, but how could it or us know for sure? Maybe if the original was still alive and reported being aware in both brains/bodies? Hmm…
ljk
You said “As for your comments on religion, the smarts ones will adapt and adjust to the times. Perhaps those who refuse to change will be allowed to live on specially reserved areas so they can carry on with their beliefs, so long as they do not pose a threat to others who do not share their views. ”
You mean, like we did to the Native Americans – put them on reservations???
I know this is a debate about interstellar travel, and the technology and engineering associated with making that happen. But really, you can’t ignore the broader issues associated with interstellar travel, which is what my comments have been focused on all along. I think the engineering and the technology will look after itself – and one way or another, we’ll find a way in terms of propulsion and spacecraft engineering to get to the stars. But when we do, I hope we are worth the effort as a civilisation and a species. You must remember that even those who dream of becoming ‘post-human’ will not be entitled to impose their will on those who aren’t as if they were Gods.
If you really believe what you are saying – then how is that different ethically from slavery? Slaves were forced into a life of pain and misery because of the colour of their skin. Do normal humans suffer the same fate because they choose to remain human? Do they get a choice? Why not solve the whole problem by wiping the normals out? Forced sterilisation of anyone who is not post-human? Echoes of the Holocaust? Do you see it necessary to embrace the darkest parts of our past to achieve the dreams of the future?
And what happens at some point, once post-humans are exploring interstellar space, when they have first contact with an intelligent extraterrestrial civilisation? Lets say, hypothetically, that the ETs are ‘meat based’ – not ‘silicon based’. Let’s say they have their own religious beliefs that makes them repelled by post-human concepts. Do you put them on a reservation too because they are seen to ‘pose a threat’ to the post-human society? Or maybe annihilate them? By 200 or 300 years into the future I’m sure we’ll have some pretty awesome weapons of mass destruction that could do the job quickly and efficiently? Is that to be our future legacy?
Maybe I’m reading too much into your words, or maybe you are just saying such a thing to get me to respond. I hope that is the case. Because if you really believe that the best future for non post-humans is to stick them on a reservation, then that’s a very dark future indeed, irrespective of whether we get to the stars. Maybe, with that future, we don’t deserve the chance to achieve such a goal. If that is what post-humans are seeking – to become Gods that can impose their will on others – I want no part of it, and I’d oppose it even if it means that don’t get to the stars. (It won’t be up to me, but future generations to fight for what is right and oppose what is wrong). If we go to the stars we should be bringing the best of humanity with us, not the worst aspects.
Malcolm Davis, what I thought I was trying to get across is that if Earth becomes even more technologically advanced and spreading civilization across most of the landscape (and oceans, why not?) filled with people who are genetically engineered and/or cyborgs, making themselves far different and more sophisticated than when we are now, what is to become of those people who do not want to change? Is it better to make them fit into such a society or let them be themselves in areas purposely untouched by modern technological society?
This very thing has been going on for a long time now. Think of the few native tribes left in South America, who are having their habitats deliberately destroyed by the more advanced societies all around them. Since we cannot seem to stop this encroachment on their lands and way of life, is it better to try to make them more like the modern populace or try to give them a place to live their lives the way they want to? And how long before those regions are taken away from them as the land is considered more valuable than their lives? And how do we stop this from happening? Have the USA go to war with various South American nations, thereby imposing our will upon them?
I had a feeling my comments would stir up righteous indignation, but the point is the world is changing and a growing population is expanding across all lands, a population that for the most part does not want to return to a more primitive way of life. Note how many “primitive” cultures who encounter modern civilized humans often want to join in with all the goods and better weapons that civilization has to offer. Now do we deny them technology and medicine because we want the natives to live the way we think they want them to live? Is that any less cruel?
The point I was trying to make was there are no easy answers and very often Westerners with good intentions do not really understand or appreciate what those rainforest tribes often have to go through. No shock to learn that they too often prefer a better life that modern society can offer. Now do we deny them this? And for those who do want to live more simply, where and how do we do this without the need for reservations?
When the time comes to start human teleportation trials or destructive mind uploading, followers of any religion that holds dear to the judeo-christian ideals pertaining to ‘souls’, seem to me to be in for a time of personal crisis. However, I don’t find that particularly relevant to the discussion at hand for several reasons; strongest among them is the notion that sending ‘yourself’ to the stars will be an all-or-nothing deal (as previously so eloquently mentioned re. copies/avatars that will also merge their ‘memories’ upon return with ‘you’ who stayed home).
I cannot easily imagine a situation where the only instance of a person is ever sent on an interstellar ‘voyage’ once the time has come for us to upload (in order for the discussion to be about beaming ourselves to the stars) ala Kurzweil et al. By then the human race will have changed enormously so that discussions like ours today will probably be seen as quaint at best and alien at worst. I refrain from extrapolating the fate/state of todays religions to this future date, nor the effects upon them of those soon-to-come times and how they will change to accomodate the changes to society… this is beyond the scope of the topic at hand.
One thing is clear and has already been stated, societies and subsets of those societies will do as they see fit under external forces/impetus. Those with objections to anything will steer clear of that thing. If the concept of the soul prevents someone from undergoing teleportation or much more likely, uploading, then that’s their choice but that doesn’t directly affect my choices, nor should I tolerate it affecting my choices. This implies that the section of humanity who upload (and travel to the stars via this method) will be from the section who do not place such religious restrictions upon themselves and who make their choices, also freely.
So either humanity splits into those who refrain and those that undertake uploading (assuming uploading is destructive), or the tide of change gets us all and we, as an overwhelming majority, change together as a species. Personally I think the second one is more likely and we’ll all embrace the same path as we will have different values then than now. I’m 42 and the world of my two young children is much different to mine was at their age so I can fully imagine a post-human future might not be too far away. Should organised religion and so many other human institutions survive such a change (gradual or sudden) it would be interesting to find out how.
@Malcolm Davis – I’m sorry I gave you the wrong impression about the post-human future. Let me use a contemporary analogy. I cannot, for simple genetic reasons, be a male model, or super athlete. My genetics just aren’t suited for either. So when I say religion is irrelevant to the super model or athlete future, that should be self evident. It is genes that count. Nor are super-models or athletes “depriving me” of that future, I simply cannot be part of it for genetic reasons. But I think that we can also agree that super models and athletes are not gods or super humans either. When I see a post human future, it is for humans partially adapted for living in space. That may be as simple as having the physiology for radiation tolerance, very high acceleration, or low gravity.
Either of those attributes might be necessary to live better in our space colonies in the solar system. If we are talking more extreme development, e.g. living as mind uploaded beings, it may be that only that approach will work effectively to colonize the stars. One can wish for high c travel, but if beamed minds is the simplest and cheapest solution, those people will colonize the stars long before humans 1.0 get there.
I’ve made this general analogy before, which I think was originally suggested by A C Clarke. We may be like fish pondering the colonization of dry land. Fish will think about building artificial inland seas (terraforming) and building mobile aquariums (worldships) to get there. But we know that land colonization was only achieved by their descendents, the reptiles. So it might be in space, that we humans will not be the most suited to colonize it.
I hope that clarifies my views somewhat.
@NS:
I think we’d have no choice but to accept the replica’s claim. What more verification would you need? Would it be ethical, even, to second-guess the replica on this matter?
This cannot happen for many reasons. The original would simply have to accept that they were left behind in their old body, and wish the replica good luck. After the upload, they would be two independent persons, with similar personality and a shared set of memories that would (at least initially) make them closer than any twins could ever be.
Malcolm Davis:
You are right about all the ethical issues you mention. Think about it, though: Many of them are already faced today by physicians contemplating difficult procedures in which the patient may survive in a vegetative or severely impaired state of mind.
Some, on the other hand, are new, those specifically concerned with duplicating the mind. How will original and replica share their estate? Their family? And some of the other things you mention. All serious ethical and legal issues, but not really more challenging than many others that are being addressed by our existing legal and ethical frameworks. Innocence by insanity, adoption, dementia, mind-altering drugs, in-vitro fertilization, surrogate parenting, etc. All thorny issues that we have learnt to deal with. We will just have to deal with these new ones, too. Not such a great deal, in my opinion.
In these matters, ethics and the law must follow technology, for better or for worse. For the most part, it would be futile to try and stop progress until ethical concerns are fully sorted out. One important exception, in my mind, is the possibility of doomsday weapons. Would it be ethical to allow research into pocket sized nuclear weapons? Biological warfare agents? This bothers me much more than any issues associated with the duplication (or creation) of minds. Some of this is actually relevant to starship propulsion, as well: Miniature bombs and space based ultra-energetic laser beams are contemplated for some designs.
NS:
The first of these two rings quite true, but the second is neither a consequence, nor similarly evident. Consciousness comes from the brain, obviously, but its nature might be sufficiently well described on a level much more abstract than the connections between individual neurons. Say, as a chain of thoughts and feelings which are driven and deflected by external stimuli and internally stored memories.
The way in which a good book can practically, albeit temporarily, transport our mind into an imagined world makes me think that this might be easier than most of us now think. Words are close relatives of thoughts, and we routinely bandy about “pieces of our mind” using language. Small pieces in conversation, larger pieces in books. The question is, how large a piece do you need to build a credible replica? How much fits in a book? And what technologies might we need to bridge the gap?
Contemplation of brain injury puts a rough upper limit on the fidelity that is needed, in th 60-90% range, I believe. The most difficult part is to reverse engineer the rules by which thoughts and feelings run, dynamically. If we ever know enough about these rules to bring a replica to life, our implementation will, in my opinion, resemble a computer program much more than a brain.
In the end, I think, mind uploading will simply be a practical component of artificial intelligence. A way around the dilemma of having to make up a mind from whole cloth: It should be much easier just to copy from an existing one.
For those who might find this interesting, here is a link to the Blue Brain project http://bluebrain.epfl.ch/ and the wiki page for mind uploading in general http://en.m.wikipedia.org/wiki/Mind_uploading
Eniac said on October 13, 2014 at 22:32:
“Innocence by insanity, adoption, dementia, mind-altering drugs, in-vitro fertilization, surrogate parenting, etc. All thorny issues that we have learnt to deal with. We will just have to deal with these new ones, too. Not such a great deal, in my opinion.”
I have read at least one science fiction story (and I have no doubt there are many more of the kind I am about to describe) where every human has been “cured” of violent and insane behaviors. The result was a society of pleasant, “happy” drones who never caused any problems (mainly independent thoughts) and did what they were told. Thinking “dangerous” thoughts were not only forbidden but incapable of happening.
I just thought of two popular SF stories in similar veins to this: The 1992 Demolition Man and A Clockwork Orange in regards to the Ludovico treatment.
Humans are far from perfect and will probably remain so as long as they remain human. But so far we have managed to not only build a technological society and even traveled into space, but we have not totally destroyed ourselves yet (just don’t read today’s news, okay?). And despite my Catholic upbringing telling me to be an obedient little servant who never does anything wrong, it is usually the radicals of society who make things happen – and then become copied and become the new paradigm until the next radical comes along.
Eniac then says:
“In these matters, ethics and the law must follow technology, for better or for worse. For the most part, it would be futile to try and stop progress until ethical concerns are fully sorted out. One important exception, in my mind, is the possibility of doomsday weapons. Would it be ethical to allow research into pocket sized nuclear weapons? Biological warfare agents? This bothers me much more than any issues associated with the duplication (or creation) of minds. Some of this is actually relevant to starship propulsion, as well: Miniature bombs and space based ultra-energetic laser beams are contemplated for some designs.”
This is why every time I read here and elsewhere about a form of interstellar propulsion that involves big bombs and laser/particle beams, my first thought is who is going to fund this? And the answer is usually always the same: The type of people/organization that wants such things for far more immediate and nonscientific purposes. Think DARPA and their interest in the 100 Year Starship. Or how about the 1985 film Real Genius where a bunch of really smart college kids help build a 5-gigawatt laser and only later in the film question who would want such a device and why.
Now what is it going to take for that to change? Will pure science and the advancement of human knowledge ever be enough? Can science and the military-industrial complex ever work together in a way that won’t have the potential to ruin the day of everyone on Earth?
The legal ramifications of copies/human uploads seem like a minefield and will have to be addressed long before we get to that level. Will a terminally ill billionaire still have full access to his/her estate after they’ve been uploaded?… how about the rights of a younger person whose life will be cut shorter than it should’ve been by disease or a genetic glitch where the cure involved uploading to a working artificial body/substrate? There is the excellent ‘Permutation City’ by Greg Egan that partly addresses these issues, as does ‘Accelerando’ by Charles Stross. Accelerando also explores sending uploaded avatars on an interstellar sail voyage; the ship is a diamond substrate no larger than a can of Coke.
Max Tegmark once proposed an interesting conundrum re copied humans. Imagine you are sedated in a hotel room on the second floor and a perfect copy of you is made and one of the two ‘yous’ is moved to a room on the third floor. When both copies are awoken, which room do ‘you’ wake up in? (The idea was presented as part of a program on the multi-verse but it’s pertinant here)
Both copies would be you. Even after leaving the room and aquiring different memories they would both be you, just different versions of you. Lacking any data, how could the original know they weren’t the copy?… I don’t think they could.
It was long enough ago for me to be clueless as to the author but I read a short story once about sending copies of a stay-at-home astronaut to explore a deadly boobytrapped maze-thing on the moon. The earthbound man and his copy were somehow linked for a few minutes so they were essentially the same mind. Each time the copy progressed further until the resolution of the story where the copy finally made it through, the link faded and then there were two astronauts that started to diverge into two unique people. As entertaining as that was, I can’t see any reason to assume each copy would be linked. With two identical copies they would still have two seperate consciousnesses… the awoken copy would be identical to the saved scan at the time the original was scanned (could be months before). Essentially every copy would be a bona fide person (going along the lines of ‘backed-up’ Culture citizens in the late Ian M Banks excellent novels, or even, for those inclined, the Star Trek TNG episode ‘Second Chances’ (although the Federation has no problem recognizing Tom Riker’s rights as being the same as Will Riker’s).
Maybe cultural and societal pressures will find running more than one ‘you’ at a time taboo. Maybe legal rights can only be held by the oldest copy or a nominated copy? Maybe you can run as many ‘yous’ at whatever clockspeed you like provided you had the petaflops to do that. Beam a few copies to the several interstellar cruises that are underway just for kicks… years later these copies could be reintegrated to ‘you’ back at home. Imagine living with several lifetimes under your belt with all their varied experiences and memories… humanity will have evolved to the point of being unrecognizeable to us in the here’n’now.
Eniac, I think it likely that the replica WOULD have a separate consciousness (if it’s conscious at all), but I don’t think that’s the outcome that most people who are talking about uploading minds are after. They generally expect a continuation of their original subjective consciousness in a new body.
it seems rediculous to me to embark on a project with even hundreds of years of travel time. it’s likely they would be some way into the trip when another ship catches up to them and explains their parents died in vain as now technology means we can go there in 50 years…
there is an order of advancement that puts new ideas and technologies in stages (listed in order):-
conjecture
speculation
science
technology
application
so given that the technologies for propulsion required to shorten the trip to 50 years or below are still in the “speculation” or “science” stages it’s a long way off.
however propulsion is only part of the requirements.
i don’t know of any ship that has it’s own government, any people living permanently in space, or any manufacturing in space (food, fuel, air water etc).
perhaps it’s better to get these up to speed through colonisation of asteroids the moon and other planets instead.
Technologies will emerge from these that will solve the issues of high speed transit.
some space TECHNOLOGY we should be working on are
a space elevator
mining asteroids
living on asteroids, mars or the moon
building a permanent and self sustaining space station (with it’s own government)
we should also be focussed on raising the amount of power we can produce here on earth to enable more research and applications of new technologies through the FUSION REACTOR projects.
some people here mention fusion is 100 years away, but it’s already a technology that has been used since the 1970’s with the JET in england and soon the ITER project in 2017 will explore the viability of a powerplant when construction is complete.
the only decent fuel is antimatter which has science being studied right now, this has the highest specific impulse of any fuel available right now.
rocket propellant is just not an option, for voyager’s 37000mph travel, it will take all of 80,000 years NOT AN OPTION
http://www.engr.psu.edu/antimatter/introduction.html