It’s always good to have eyes and ears on the ground at events I can’t get to, so I was pleased when Aleksandar Shulevski contacted me with the offer to send back notes from the European Space Agency’s Advanced Concepts Team Interstellar Workshop in Noordwijk in the Netherlands. Born and raised in Bitola, Republic of Macedonia, Aleksandar is a science fiction reader and amateur astronomer who followed up electrical engineering studies in Skopje with an MSc in astronomy at Leiden University (Netherlands), dealing with calibration issues on the LOFAR radio telescope. He received a PhD from the University of Groningen, doing research on active galactic nuclei radio remnants observed with LOFAR. After working at the Netherlands Institute for Radio Astronomy (ASTRON) as junior telescope scientist, he is now a research scientist at the Anton Pannekoek Institute for Astronomy at the University of Amsterdam, specializing in low-frequency radio transients and pursuing his interest in SETI. Aleksandar could only attend half of the workshop, and unfortunately no video is available, but I’m told a fall issue of Acta Futura should include papers on many of the topics covered in Noordwijk.
by Aleksandar Shulevski
I have attended only the first day of the Interstellar Exploration workshop, organized by the Advanced Concepts Team (ACT) at the ESTEC ESA site in Noordwijk. Even though I follow the goings on in the community, I must admit that I almost missed the workshop; maybe the organizers should have advertised it more widely. Obviously this is just a personal opinion.
The program indicated potentially an interesting gathering, and I am pleased to say that I was not disappointed. The auditorium was packed, I estimate that more that the total number of participants was about 120. The technical director of ESA opened the workshop, remarking that interstellar topics are more and more in the limelight, especially since Breakthrough Initiatives launched Breakthrough Starshot: “It’s never too early to start discussing interstellar matters”.
Michael Hippke started the morning session with a popular talk on interstellar communication. He gave a thorough overview on the history of thought dealing with the problem of communicating with other worlds. The radio window was de-emphasised on account of more exotic techniques like X-ray lasers, neutrinos etc. Michael thus established the “out of the box” thinking needed for such a meeting.
Rob Swinney (BIS) gave a historical overview of fusion propulsion concepts, covering the design of the Daedalus craft, as well as the successor design effort (Icarus). His remarks were in line with his enthusiasm: “We tend to underestimate what we can do on long timescales”.
The ongoing effort funded by NASA to outline and design a mission concept for a probe to 1000 AU was the topic of the presentation by Pontus Brandt. The tentative launch date is to be sometime in the 2030s. Pontus went over past missions which are on their way out of the Solar System (Pioneer, Voyager, New Horizons), tracing their origins to a strategy for Solar System research outlined in the Simpson committee report of 1960. The committee was chaired by John A. Simpson and James A. Van Allen as part of the contribution of the Space Studies Board, which was established in 1958 to focus on space research for the National Academies of Sciences, Engineering, and Medicine.
Long term thinking is key, along with lessons learned from past experience. In a set of stunning visuals, Brandt outlined current plans. Most likely the probe will form its trajectory by a Jupiter gravity assist, burning its final fuel supply there to achieve final escape velocity considerably greater than that of Voyager 2, reaching interstellar space in 15 years. Mission goals are observations of the infrared background as well as taking the first comprehensive “outside view” of the Solar system.
Michael Waltemathe discussed the philosophical and religious aspects of interstellar travel. What if any ETIs in existence are morally superior? Will humanity export the concept of original sin among the stars? Issues like planetary protection in the interstellar context were raised, and obviously, there were few definite answers.
Phil Lubin’s presentation dealt with directed energy propulsion, discussing detailed concept designs on Breakthrough Starshot, specifically the emitter array. Excellent beam handling was reported, and no issues (apart from funding) are show-stoppers on the path of scaling up to the operational laser system. However, an issue that warrants serious research effort is the communication subsystem. Laser comms will suffer from unattainable pointing accuracy requirements. The lack of deceleration in the target system may be problematic, but potentially overcome by launching a huge number of StarChips in succession, thus replacing the need for orbiting craft. The beamer system has tangential benefits as well, like Solar System exploration applications, and planetary defense. Long term R&D commitment is needed to realize the full potential of this effort.
[PG: I notice that MIT Technology Review just posted an article looking at some of the issues involved in getting this kind of laser array operational, while reviewing other issues re Starshot that Aleksandar mentions].
The morning session was followed by a less structured period for the duration of which multiple discussion groups were formed upon the suggestion of interested attendees who proposed topics. The organizers suggested most of the questions that needed to be addressed at these sessions. I proposed to discuss the propagation effects ISM plasma would have on the radio link used for communication with a Breakthrough Starshot style StarChip. There are multiple papers on the topic and we went over David Messerschmitt’s concepts of signal conditioning, discussed at length in his book featured on Centauri Dreams in the past [for more on Messerschmitt, see for example, Is Energy a Key to Interstellar Communication?]
The discussion period was followed by a panel on which each discussion topic had a representative, and the audience had a chance to ask questions. The afternoon plenary session began with a talk by Andreas Hein on worldships, in which he presented results from his latest paper in Acta Futura. Everything else being equal, and assuming economic growth continues unabated, Hein believes Earth will be able to build a worldship in a few hundred years, although the concept of a worldship may be by then outpaced by more practical developments.
Angelo Vermeulen presented the research done by him and collaborators at TU Delft and elsewhere on evolving spacecraft which borrow from biology to convert asteroids to interstellar craft. The study focused on the life support aspects of the problem and went on to model at length various constraints like (for example) the impact of the mineral content of the asteroid being used on mission viability.
Jeffrey Punske focused on language development on generation ships. Illustrating the various (and not always obvious) reasons for language drift, he concluded that it is inevitable that the language of a generation ship will evolve so far from Earth standard in a matter of a few hundred years as to render communication between the two unintelligible, something which mission planners should take into account. He dismissed the notion that a universal translator device is a viable development. If communication becomes a ritual performed by a priestly caste on the ship using the archaic language of the predecessors, maybe communication will still be possible in some form even after the divergence occurs.
Elke Hemminger addressed the sociology of interstellar exploration. Using an interactive approach, she engaged the audience in discussing philosophical topics. What if the values we hold most dear in our current societal organization are incompatible with the mission requirements of a colony ship? What are we willing to sacrifice to make the mission a successful one? Individual freedom? Is it worth it to go to the stars if we make such sacrifices?
These are more than abstract topics and may have more immediate concern on the human condition. It can easily turn out that dealing with climate change will require modification of our values. It may well be that totalitarian societies are more suited to dealing with emergencies than democracies. How do we balance our social values against the imperative of survival?
ESA’s Advanced Concepts Team closed the session by outlining the results of the latest Global Trajectory Optimisation Competition, this time dealing with Galaxy colonization, in which three types of interstellar generational vessels are imagined to be sent around the Milky Way in a quest 90 million years long. This was the 10th edition of the GTOC competition, hosted this year by the Mission Design and Navigation section at the Jet Propulsion Laboratory. China’s solution won, in a very interesting and difficult problem posed by JPL. An August workshop will allow top teams from the competition to present papers at the Astrodynamics Specialist Conference in Maine.
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Many thanks for your report on this meeting.
Really? I have to smile at this. AFAIK, “Original Sin” is a concept that appeared in one Middle Eastern religion only. That this religion will remain dominant and evangelized to ETs seems unlikely. If religiosity remains a feature of starfarers, then I would expect many religions to be represented, all with their competing beliefs. I do hope Original Sin is not a belief that can be exported to the stars, and if it is, strongly rejected by ETs.
I cannot stress this enough. There is no scope for exponential economic growth to support this endeavor UNLESS we find a way to expand our industry and population off the Earth. The prerequisite technologies and social conditions for this are still in doubt.
A paper on this subject by McKenzie and Punske that elaborates on this: Language Development During Interstellar Travel. Funnily enough, this issue was also part of a short story by Arthur C Clarke – Cosmic Casanova, although the humor was abou physical evolution of colonists, rather than language evolution.
I admit at the outset that I have read little on the topic of interstellar colonisation. Please forgive me if I am rehashing ideas that have been written about elsewhere. That will most certainly be the case.
Personally, the concept of an interstellar “world ship” has always seemed to me highly unlikely. If interstellar travel for the expressed purpose of colonisation is ever undertaken, and I hope that it will be, then world ships have a singular critical disadvantage. High mass.
The world ship requires orders of magnitude greater mass to be moved than other colonisation options. With that mass comes a requirement for orders of magnitude greater energy to at the very least accelerate and decelerate the vehicle.
In Aleksandar’s summary, he stated that a seminar participant had postulated that ” assuming economic growth continues unabated,… …Earth will be able to build a worldship in a few hundred years” To be quite blunt, the concept seems even today like a projection of 16th century thinking into the interstellar era. Colony ships will not be living worlds. There are multiple serious social and technical reasons not to travel thousands of years like that within the bounds of a single ship or even a flotilla.
One alternative requiring many times less mass, and thus enabling far greater speed would be for lack of a better name a seed ship. A ship containing “embryonic” seeds in cryo. A conceivable conservation method necessitating no greater technology than exists today. Enter future tech now…..Upon arrival, a ship AI would “gestate” and raise/educate the first future human colonists.
A more advanced second variant would require even less mass. If we really are considering the capabilities of a Sol based civilisation in a couple hundred years as stated above, then I can conceive of a relatively small factory probe which carries little or in an extreme case no biological material. Literally everything from machines to life forms is created upon arrival in the target system using in situ resources. Built from base elements according to stored blue prints. If desired the life forms may even be somewhat or completely tailor made for the specific conditions on the target planet.
Assuming there is no “warp drive” in the future, I think the colonization method which requires the least baggage will be regarded as preferable. The concept of a world ship represents the absolute opposite.
Even seed ships need some way to gestate their embryos and raise them. This requires technology we don’t have now, although probably will have at some point. The bigger problem is that advanced biological life, like humans, needs a a fairly complete biosphere to live in, tailored fairly closely to the conditions we currently enjoy. This requires a range of organisms to keep us healthy, as well as organisms to maintain a biosphere that can sustain us. It is far easier to dispense with biology and just send artificial “life”, ie machines, in our stead. They can operate in a far wider range of environmental conditions, need no supporting biosphere, and therefore should be able to “colonize” the galaxy far more easily. Any humans following will he highly restricted in comparison. Just as the fish did not colonize the land, but their evolved descendants did, we should accept that we are more akin to the fish, than their descendants.
Predicting what capabilities and even priorities a society will have centuries hence is of course a fool’s errand. In my little comment, I concentrated solely on what I think are anachronistic visions of human propagation via world ships. Your point that colonisation by purely artificial “life” may be the simplest variant is, however, well taken. It ties into what I said above regarding the unknowable priorities of distant future society(which of course may or may not be at the time unisono). Today, our millenia old traditions of terran colonisation still color our outlook on the future. I expect perspectives on this will radically change as we garner more and more technical capabilities. A much hyped technological singularity for instance could potentially kill our old expansionist impulses. Stellar colonisation? Meh. Then again I can at least conceive of scenarios, benign and otherwise, where this impulse is accelerated by such a singularity.
Our self identity and concept of destiny will change as our world changes. And I think in much more far reaching manners than most today can conceive of. The future will not be simply like the past only with jet packs. Primarily because our very concept of self will change beyond recognition.
I think that we humans will still want to visit other worlds personally, inefficient or not. After all we can see now a huge number of photos and videos of every country in the world and almost every aspect of the life there and still people travel to the other side of the world all the time.
We will go. Hybernated or whatever, but we will go.
It really depends on what one means by personally.
Consider: Any hominim could walk around their continent within their lifetime. When ocean going ships were developed, that extended to seeing anywhere on the planet. With modern air travel, almost any place on the planet can be reached in a day.
Consider: Even with our chemical rockets, in principle, a person could visit all the planets in our solar system within their lifetime. A space-going liner of cruise ship dimensions, with a few hundred passengers could conceivably do tours of the solar system, if boredom between the worlds was tolerable.
But now consider interstellar travel: Only trips to the nearest stars are possible within a human lifetime, and that requires travel at fractions of c. It would require close to lightspeed to achieve time dilation to allow further distances to be traveled in a human lifetime.
We don’t know if cryo-preservation can even in principle allow a human mind to be projected into a future well beyond a nominal lifetime.
At present, the only way we can conceivably colonize worlds with humans is to carry frozen embryos and nurture them at the destination, as John Walker has suggested. Although the nurturing by robot AIs is currently an issue, I don’t see it as a long term problem once a number of generations have passed and the early, “damaged” humans are no longer around. World ships offer another option, but again, not for personal travel. The slow speed of travel would most likely mean that any destination would long since have been colonized by the time a worldship arrived.
Without some magic pixie dust technology, I see little hope for personal interstellar travel for humans in our current biological form. If, a very big if, minds can be decoupled from our wetware, then personal interstellar travel may be possible using any number of transfer methods. Some people say that still isn’t personal as a copied mind is not “you”, but someone else.
“Only trips to the nearest stars are possible within a human lifetime”
Human lifetime is not a constant, it has been changing in the last centuries. It nearly doubled in most of the world in the 20th century. Of course, a lot more change is needed for interstellar travel, but that will surely happen.
– On the long term, some form of hibernation / suspended animation will be developed (the problem actually is dehibernation, not hibernation).
– On the near term, aging will be cured, probably by 2040 or so. That means having the death rates of a young person (say, in their 20s), or, equivalently, a life expectancy of around 4,000-5,000 years, with current accident rates, etc.
“We don’t know if cryo-preservation can even in principle allow a human mind to be projected into a future well beyond a nominal lifetime.”
We do know.
 To be precise, we will reach longevity escape velocity: https://en.wikipedia.org/wiki/Longevity_escape_velocity
The upper age of humans has not changed, just the reduction in mortality at younger ages. There is no evidence that this upper limit can be breached.
Hibernation does not extend lifetimes. It needs true slowing down or stasis of life processes. We cannot do that for large organisms, and there is no obvious prospect of being able to do so. We might be able to induce hibernation to reduce metabolism and consumables, but remember that animals that hibernate store large body fat reserves to survive winters by sleeping and not eating.
The idea that we will have a “longevity takeoff” is fantasy. As for Aubrey deGrey, he has had quite a lot of time now to come up with any results supporting his various proposals for life extension. AFAIK, none have shown any significant promise. I suspect this is just another aspect of the wealthy wishing to live forever, whether by life extension, cryopreservation, or mind uploading with the singularity. May he and others continue to part money from the desperate.
I stand by this. Your references are for nematode worms and thin brain slices. We know we can freeze many small organisms, including early stage human embryos. That is a not the same as doing the same for larger organisms, starting with even the smallest of mammals. Animals that can be put into stasis, like tardigrades, do so by dessication, and again, only the smallest of organisms can do this.
“…wishing to live forever,… … by mind uploading with the singularity.”
When will this fallacious idea finally finally…die? One’s own sense of self will not be altered if a duplicate of one’s mind is “uploaded”. Even if the process involves some bizarre evacuation of the brain’s contents leaving nothing behind. Such a process does not extend the life of the original. The artficially stored mind may contend that a continuum exists between the old and the new shell. But, that is an illusion. Just as in the case of a Star Trek like transporter event, the original dies. No immortality for you.
I have to disagree with you . If the copy contends that it is continuous, then it is. I suspect that this novel situation, never before experienced by humans, makes it very hard to wrap out minds around this. From the perspective of the original, nothing has happened other than a copy now appears. For the copy, the POV is that the sel;f has moved to a new body. As a thought experiment, imagine that a replicator has made a copy, but in the process obfuscated which is the original and which the copy. Without any way to tell the 2 apart, there is no way to claim who is contiguous and who not. If one is destroyed in a transport device, then the “copy” will just think it has been transported to the new location. The idea that the “real you” has died, and that some other, “not you” has been transported makes no sense to me.
Suppose we slow down the transfer process instead. Incrementally replace each nerve cell with an artificial copy until over a period of time the brain is replaced with an artificial one. Your sense of self will not disappear as the replacement is made. That artificial brain can be moved to a new body and you would move with it. As your brain is already being replaced molecule by molecule, this is already happening at an even more micro scale, if any form of replacement (molecular, artificial nerve cell) or copying creates confusion in the location of identity, it shouldn’t.
Interesting, indeed! Of course cultural evolution proceeds by perhaps orders of magnitude faster than biological evolution. Already Shakespearean or Elizabethan English begins to be quaint or even strange. And with a timeframe of 90 million years into the past our ancestors were tiny shrew-like animals scurrying through the underbrush or living in trees, while dinosaurs roamed the earth.
“Original sin” as referred to, is a feature of the Abrahamic traditions, not found in indigenous and Indic world-views, nor even in Kabbalah. It is not a feature of all humanity.
Success at multicellularity requires strict regimentation of at all levels from individual cells to the entire organism. Any uncorrected deviations result in disease and/or death. However this results in limitation of the number of responses to situations previously encountered and adapted to in evolutionary history; novel situations may not elicit appropriate responses.
In contrast, human societies have individuals that can “think for themselves”, although this could be degraded by stricter regimentation. Maybe this would not be a problem with artificial intelligence as in matrioshka brains.
A very interesting debate. As far as seed ships go I have at least one major concern. Having machine intelligences raise the human young after arrival at the target planet necessitates huge psychological risks. Nurture is an extremely important biological concept. Children who are raised by adults with serious psychiatric issues and who do not receive constant physical love from parents are often very disturbed behaviorally as adults. Jeffrey Dalmer comes to mind. I don’t think the seed ship concept can work unless it includes adults who are in suspended animation. The mass issue is of course another huge problem. I think the future is not likely to include human colonization of other planetary systems within the next few hundred years unless gigantic and unforseeable advances are made in a large number of disciplines. I do think it will be possible to spread throughout our own solar system in a large number of habitats (as with many of Kim Stanley Robinson’s and many others’ stories).
Original Sin is not a Jewish concept and I would argue Christianity is more Greco Roman.That said Alex is right about humans and worldships.
I Found the news on Breakthrough Starshot really exciting. I wonder is Aleksander with us background might have some ideas on communication with starshot.
Great summary Aleksander.
“Michael Waltemathe discussed the philosophical and religious aspects of interstellar travel. What if any ETIs in existence are morally superior?”
They will have to be, although I cannot explain why I think this within the confines of Paul’s rules (which he has every right to set) about no religious debate.
In my opinion we will go the slow way, world ships can be self supporting and don’t need a star to function if we have fusion power. Silicon sleeves with our personalities perhaps could be launched much quicker if we could download copies of our minds into them. Knowing a copy of me went there to another star would still be immensely fore filling to me at least.
I’ll attempt to respond in one comment to the questions raised in previous comments.
The original sin mentioned in the report was just one concept highlighted in the relevant talk. The speaker did a very good job in addressing interstellar travel from a theological point of view. I can appreciate the issues religious communities have (will have) with these concepts as we expand into the void, although I do not share their concerns.
The world ships are indeed food for thought. High mass and low speed raise multitude of issues from feasibility to sociology. The speakers talking on world ships were aware about these limits and they spoke openly about them. Still, world ships present a valuable tool, a laboratory if you will for exploring various topics, as were discussed at the workshop. Not least because we inhabit a world ship and we need knowledge how to solve the problems we’re causing it.
Sending out embryos was discussed, even though reading what I noted I may have given off the impression that it was omitted, sorry about that. Issues with how to raise the embryos so that they grow up to be human is a tough one. Another topic which received attention is: what does it mean to be Human?
Communicating with the star chips launched by the breakthrough initiative is a tough problem. It’s under active research, and I touched upon it in the panel I led. Most likely laser comms are the answer, if the issues around the pointing stability are tackled. Otherwise, solutions like foldable phase arrays for radio communication may work, however design complexity and available power are an issue for those solutions.
Communicating with the star chips launched by the breakthrough initiative is a tough problem
Communication with craft that is planed by breakthrough initiative and our present technology is impossible, even one way messaging from space craft located on interstellar distance to the Earth is impossible.
Very serious jump in the Earth’s science and technology required to make it possible.
I can’t see it been that big a problem because by the time it gets there 20 years we could have built a very wide based receiver using Starshot launched probes.
Wide based receiver is good for measurements (spectrometry, distance, direction finding etc. ) , but physical laws still dictate one simple postulate – antenna efficiency (gain) is defined by effective antenna’s area, we do not have other physics meanwhile.
So the best antenna shape is still remains a EM waves reflecting parabolic surface. It is possible to replace parabolic mirror by phased antennas array, but it will be much more complicated, much more expansive, significantly less effective solution that still limited by effective area constrain and minimal distance between antennas in array , this distance has to be in order of half wavelength…
There still remains the MAIN problem of this communication link – limited output power of breakthrough interstellar probe. So Probe’s weight and size limitation make interstellar communication (even one way) with breakthrough probe impossible on our present technological level.
Thanks Aleksander. Really glad to know you are on This .
It might seem odd that of all the conjectural issues concerning interstellar travel, we should find “original sin” as much of a stumbling block as efficient propulsion, general relativity or surviving warp drives. Because first we’ve got to find an ET audience to address these topics to. And then, just like everything ELSE about human experience, we are confronted with the difficulty of conveying it.
My initial conjecture is that something like a specialized use of the Drake equation might apply. World ships would set off toward nearby stars with planets that are habitable in the sense that they can be seeded, but that the set of such worlds will be small indeed that have
much more than bacterial life and corresponding biospheres.
But let’s just say that we get lucky (?) early on. What to do?
In many cases, when we speak of these things, it is like discussing whether when you see or think about the color “yellow”, it is the same yellow that I think of or see. Maybe the alien will feel or hear it instead.
Thus far, here on Earth, things of this nature have been difficult to convey to dolphins, whales or other large brained co-inhabitants. Surprisingly or not, little mental energy has been directed at how it would apply to them. Which suggests that many adherents to the doctrine or belief don’t think it does. It seems that these creatures are not enough like ourselves.
Assuming that extraterrestrials are much like ourselves, which does not appear likely right now, then we also have to consider that this issue has come up before. And it was a two edge sword. When the explorers from the newly united kingdom of Spain reported back on conditions in the western hemisphere, the philosophers – or what passed as such – deliberated as to whether the inhabitants of the New World shared this legacy – and then what to do about it. They were aware of China and India, but the notion that whole continents of the world had existed all along without any prior evidence – it literally floored them. But since they finally decided that the inhabitants were much like themselves, they thought it applied. They might have even seen it as a way to remedy things that New World inhabitants suffered from. Collectively we might not see it that way, but note the idea of “remedy”.
There is some science fiction that has addressed this particular question. And in some of these cases, from the standpoint of belief, they considered or conceded the possibility that the concept of “original sin” did not necessarily apply to other sentient creatures that live in the cosmos.
And should anyone radio back to Earth from their world ships, you can well imagine that back here on Earth some will pick up the matter again; because that is among their own questions about the cosmos, just as there is a question about whether human life and intellect is unique or not.
But looking at this matter from another angle, if “original sin” were not already a concept of religious belief, then it would be waiting off stage to be invented in some form, particularly in circumstances such as these.
It is already a widespread metaphor.
The first time I noticed it used outside a directly religious discussion was as a critique of the US Constitution. Writer Walker Percy, back in the 1980s referred to slavery as the original sin of the foundation of the American republic. He wasn’t the last and probably not the first. Then there is the whole matter of moving out of the woods from a life of hunter gatherers. All our problems would be solved by urbanization, right?
But there’s more. Because we are talking about contact with other planets and other potentially sentient beings. We send an interstellar craft with people on board and we are carrying very heavy freight indeed. And if they make any mistakes … If the planet’s life withers with their advance or all the inhabitants die of a cold, what then? It the inhabitants claim that we made them a tempting offer… Or are we just going to re-frame the whole dilemma and refer everyone to a story about Pandora and an intriguing box?
It’s not about the other guy. It’s still about us. In such circumstances I doubt if our heirs will be able to shove the notion under the rug.
But then, what if they were to inquire about it?
Humans won’t be going to the stars until we’ve found a target and performed recon using automated probes. Even if we find an interesting Planet, there won’t be one where humans can turn up and start living there. Either they have Life and we wouldn’t survive the alien biosphere, or there isn’t life and we’d need to Terraform. Terraforming would take hundreds of years, even with futuristic massive scale technology. It’s the “where you going to go?” problem.
More likely we’d colonise the Solar System and gradually spread out until our sphere of influence extends far enough that the closest Stars come into reach. Artificial habitats will have to be perfected so humans can survive in space before interstellar arks are even contemplated.
That still leave probes for interstellar exploration. It’s all going to take an extraordinary amount of time. How can civilisation stop destroying itself with our flawed political systems in the mean time? A better way of organising ourselves is the real problem. Once you’ve got that sorted the Galaxy is your Oyster.