Browsing through the correspondence that makes up Freeman Dyson’s wonderful Maker of Patterns: An Autobiography Through Letters (Liveright, 2018), I came across this missive, describing to his parents in 1958 why space exploration occupied his time at General Atomic, where he was working on Orion, the nuclear pulse concept that would explode atomic devices behind huge pusher plates to produce thrust. Dyson had no doubts about the value of humanity moving ever outward as it matured:
I am something of a fanatic on this subject. You might as well ask Columbus why he wasted his time discovering America when he could have been improving the methods of Spanish sheep farming. I think the parallel is a close one… We shall know what we go to Mars for only after we get there. The study of whatever forms of life exist on Mars is likely to lead to better understanding of life in general. This may well be of more benefit to humanity than irrigating ten Saharas. But that is only one of many reasons for going. The main purpose is a general enlargement of human horizons.
But there’s the thing, the driver for the entire Centauri Dreams effort these past twenty years. Just how do we go? And I mean that not only in terms of propulsion, the nuts and bolts of engines as well as the theory that drives them, but how we move outward carrying the cultural and scientific values of our species, Dyson thought deeply about these matters, as did Shklovskii and Sagan in their Intelligent Life in the Universe (Holden Day, 1966), who mused that an advanced civilization might view interstellar travel as a driver for creativity and philosophical growth. Perhaps culture remakes itself with each new exploration.
Greg Matloff’s investigations of these matters in numerous papers and key books like Deep Space Probes (Springer, 2005) have laid out the propulsion options from Project Orion to beamed lightsails, but his new paper, written with the artist C Bangs, draws on Dyson’s Astrochicken concept, first published in 1985, one of the few times I’ve seen it discussed in the literature (although I gave it a look in my 2005 Centauri Dreams book). Astrochicken was to be a one-kilogram probe to Uranus, a genetically engineered device powered by artificial intelligence.
As Dyson describes it in Infinite in All Directions (Harper & Row, 1988), “The plant component has to provide a basic life-support system using closed-cycle biochemistry with sunlight as the energy source. The animal component has to provide sensors and nerves and muscles with which it can observe and orient itself and navigate to its destination. The electronic component has to receive instructions from Earth and transmit back the results of its observations.”
Integrating all of this is artificial intelligence, creating a probe “…as agile as a hummingbird with a brain weighing no more than a gram.” Some years after Dyson introduced Astrochicken, Matloff discussed such a living probe, flitting from world to world, in Deep Space Probes, seeing elegance in the idea of wedding biology to technology. There he imagines a spacecraft like this fully fleshed out in the interstellar context, with a harvesting capability in the destination star system. He describes it thus:
…a living Astrochicken with miniaturized propulsion subsystems, autonomous computerized navigation via pulsar signals, and a laser communications link with Earth. The craft would be a bioengineered organism. After an interstellar crossing, such a living Astrochicken would establish orbit around a habitable planet. The ship (or being) could grow an incubator nursery using resources of the target solar system, and breed the first generation of human colonists using human eggs and sperm in cryogenic storage.
We have in this symbiosis of plant, animal and electronic components the possibility of leaving the Solar System and conceivably creating a von Neumann probe that combines engineering with the genetic manipulation of plant and animal DNA. Our probes need not be robotic, or at least entirely robotic, even if humans are not aboard.
Out of this seed comes Space Butterfly, aptly named for its large, thin wings that can unfurl for a close stellar pass for acceleration and trajectory adjustments. In the new paper in JBIS, Matloff notes that this is a spacecraft with an affinity for starlight, using its wings as solar panels to power up its suite of scientific and communications equipment. Driven by its AI brain, it would be capable of mining resources found in exoplanetary systems, moving between stellar systems in passages of millennial length. Here I’m reminded of the oft-cited fact that only a small fraction of the Sun’s projected lifetime would serve for such space butterflies to explore and fill the galaxy, even moving at velocities that exceed Voyager by only a small amount. Quoting the paper:
Using hyper thin all-metallic sails and close perihelion passes, Space Butterfly could traverse the separation between neighboring stars in a few millennia. If it elects to come to rest temporarily within a planetary system, it can decelerate by electromagnetically reflecting encountered interstellar photons and pointing the fully unfurled sail towards the destination star…
If ET elects to construct Space Butterflies with very long lives, many spare AI ‘brains’ could be carried. This should produce no major problem since these units could have masses well under one gram. Spare parts could also be carried to replace non-biological portions of Space Butterfly.
Image: Flitting from star to star, the Space Butterfly concept is perhaps more like a Space Moth, with its affinity to starlight. Credit: C Bangs.
Plugging in the known characteristics of the interstellar object ‘Oumuamua, Matloff speculates on its characteristics if it were a Space Butterfly, exploring the kinematics – trajectory, velocity, acceleration – of this kind of probe. He uses a framework of mathematical tools that have evolved for the analysis of sail technologies, ranging from the lightness number of the sail (the ratio of radiation pressure force on the sail and solar gravitational force on the spacecraft), as well as radiation pressure from the Sun at perihelion, given what we know about sail materials and thickness.
If ‘Oumuamua were a sail, it would be a slow one, moving at an interstellar cruise velocity in the range of 26 kilometers per second, and thus requiring a solid 50,000 years for a crossing between the Sun and the Alpha Centauri stars, for example. A Space Butterfly should be able to do a good deal better than that, but we are still talking about crossings involving thousands of years. Civilizations interested in filling the galaxy with such probes clearly would have long lifetimes and attention spans.
Such timeframes challenge all our assumptions about a civilization’s survival and indeed the lifespan of the beings who operate within its strictures. Given that we know of no extraterrestrial civilizations, we can only speculate, and in my view the prospect of an advanced culture operating over millennial timeframes in waves of slow exploration is as likely as one patterned on the human model. A sentient probe carrying perhaps a post-biological consciousness not at the mercy of time’s dictates might find ranging the interstellar depths a matter of endless fascination. For such a being, the journey of discovery and contemplation may be of more value than any single arrival.
The paper is Matloff & Bangs, “Space Butterfly: Combining Artificial Intelligence and Genetic Engineering to Explore Multiple Stellar Systems,” Journal of the British Interplanetary Society Vol. 77 (2024), 16-19.
Your quote “breed the first generation of human colonists” brings to mind a problem with this approach.
How do you educated the new humans so that they can survive?
People are not born with any survival knowledge.
And even among natives survival skills vary very widely: Aleuts/Inuits/Eskimos are quite different from desert dwellers and they in turn are quite different from tropical forest denizens; they would perish promptly in each other’s environments.
School a set of artificially gestated and raised humans on an alien world without prior knowledge of the environment?
We are just now getting to the point
of rolling out big sheets of tech
https://techxplore.com/news/2024-07-stretchable-electronics.html
https://physicsworld.com/a/roll-to-roll-fabricated-hybrid-perovskite-solar-cells-reach-record-efficiencies/
Our hubris assumes that our current, [post] industrial, technological society is the one that should last a long time to reap the ROI of that investment. We value it as our culture even though we know that civilizations rise and fall and are replaced by new ones with different values. While we may admire Ancient Rome and can identify with it, few would want to live in that culture. A millennium from now, I doubt that the dominant culture will be much like our Western one that now dominates. They may best be thought of as artifacts that survive through deep time to convey something of the past to the future, even if by luck, rather than design.
Instead, we should imagine our culture as “selfish genes” or rather “selfish memes”, passing along informational elements through populations of different species as evolution’s algorithms change the mix of components and even how the components work. With this perspective, our most useful ideas will extend into the distant future.
Our interstellar probes with their AIs and cultural payloads would be a temporary stasis in evolution, but like a slowly evolving population that is reintroduced to a faster evolving one, its mix of genes/memes will either [partially] continue or be extinguished.
Given that our human civilization faces existential risks, fleets of probes traveling the galaxy and eventually returning might offer a reboot for terrestrial human civilization with both genes and memes, possibly changing over time as new civilizations are established among the stars and they in turn send out similar probes.
Space butterflies with a mix of technology and biology strike me as rather fragile. They may need to be released in vast numbers with the hope that some may survive the rigors of millennia of hazards, especially radiation, and be able to reproduce in other systems. But if they can, perhaps they are best suited to reproduce first in the Kuiper belt or Oort Cloud, before striking out to the stars in vastly increased numbers. While biology reproduces, I am not sure how cyborgs can do so without a technological infrastructure. How would that be booted up in another system, especially from such a minimal probe?
How a CPUi is made
Even comparably simple biological systems do indeed have a capacity that outmatch the most advanced AI / neural network systems we can construct today.
An ant, can do construction work for the colony, farm mushrooms underground, navigate the outside with great precision and even construct bridges with their own bodies to make other pass when it’s time to move from danger such as fire with just 200 000 neurons.
Bee’s and wasps are even more advanced, with 3D navigation, communication but also able to identify the faces of others in the community. This is done with ~900 000 neurons.
Refining the traits needed for space exploration would make possible one extremely capable command and control unit for such a space probe in a space quite smaller than a pinhead perhaps a volume of ~0,001 square mm. The challenge to create an equally small and lightweight life support system will be quite a task also.
But this could indeed be a working solution, also for the idea of those laser sails such as Breakthrough Starshot considers.
Where one electronic component in a processor would get irrecoverably destroyed and lost could compromise the entire mission. A biological system could be given an boosted ability to repair, even the genes themselves via excision repair mechanisms. Such a lightweight probe would not be able to carry enough shielding so the modified cells would have to be doing constant emergency repair by RecA and LexA proteins. Yet the bottom line is that I actually think this might actually be doable! So this is one interesting concept indeed.
“perhaps a volume of ~0,001 cubic mm” (mm³)?
Ideally, a space butterfly should be tiny, sustainably built from resources available in space, and tough enough to withstand anything. The wings should be atomically thin, yet capable of absorbing sunlight for energy. It should be conductive, built of tiny independent pieces the size of a protein molecule that are OK with vacuum and ionizing radiation. They should be able to communicate with one another by emitting signals based on their internal state.
What I’m thinking of, then, is cosmic dust, which pervades space, made largely out of graphene. Chang’e 5 just found a graphene layer on the Moon too. One part in 300 of the Sun and its wind is carbon, providing an endless source of nutrition, Graphene – a material for solar cell development – can presumably extract energy from sunlight as well.
It’s clear that cosmic dust can be formed. The question is if it can do the scholarly work of a space probe. We have simulations ( https://arxiv.org/pdf/2405.12632 ) that promise interesting things. The one I linked suggests “temperature” doesn’t adequately describe the innards of a ball of ten thousand carbon atoms, and that quantum interference effects of free electrons might affect astronomical observables. The grains can emit radiation that is not simply black-body. Can the grains influence one another’s logic states, either directly or via intermediary charged particles? We have to face the same-old-same-old problem with alien computers: you never know if you’re looking at a library more massive than all the history of the Earth, or just a rock.
But just suppose, what if that cosmic dust, in all its myriad shapes, contains a network of knowledge? If the constants of physics and the presence of Earth have convinced some that the modern universe was in some way pre-configured for life, well, could it have been pre-configured for the spontaneous operation of a universal and pervasive intelligence throughout all of space?
Kinda reminds one of The Black Cloud.
@Alex wrote :
“transmit information to populations of different species/ From this perspective, our most useful ideas will extend into the distant future.”
Alex raises an issue that seems crucial to me: it is not the technology that matters the most, but the Information that is conveyed through space and time from us to furure generations, to our future machines, programmed or self-replicating, or to other ETI. What information do we want to transmit? How to preserve it? How to adapt to its future environment? whatever is decodable? etc
Technology will follow, at least, it will have to follow, and that is the challenge: to transmit information. How to program an instrument (metal or biological or both) to react in 50 or 500 million years?
We think of the movie “Contact” or they can’t decode the plane of the machine because it is in 3D…but note that they build it once they have the key, either because we give them; either because the human brain is able to conceptualize but always with elements it knows (except abstraction of mathematics, which is a separate case and an enigma)
Another example: we are still not 100% sure how the Egyptians made their huge pyramids: we have an idea of the technique – which we can rebuild – but we still do not have the exact instructions, and it was only 5000 years ago! Same for the Anthicyter machine etc I always wondered what will happen the day or a ETI will find a CD Rom when our species will no longer be there;)
So it is the information that matters and the technology that follows. What are we looking for in the universe? information!! (…which will confirm life, the presence of an ETI or other things and only then will we build machines or dialogue. There is a kind of logical progression.
So it’s the information that matters and the technology that follows. What are we looking for in the universe? information!… which will confirm life, the presence of an ETI or other things) and only then will we build machines to learn even more; adapt or even try to dialogue with an ETI.
I think we should not confuse three different but complementary things: 1) the concept, which allows us to imagine everything we want or almost 2) Evolution, which is inherent in each era let’s say that it is the part of the concept that we manage to make 3) the technology that is the culmination of the other two.
Here, the article makes “simply” slide the problem of purely material technology towards biotechnogia, since we have obviously just passed this new stage of evolution. but we always come back to the same question: how to keep information (in DNA?) how to ensure that it is correctly read and used in millions of years to millions of km from the earth…
In terms of living craft—maybe asteroid “digestion?”
This seems very apropos: https://www.sciencealert.com/engineers-gave-a-mushroom-a-robot-body-and-let-it-run-wild