Martin Rees’ ideas on how humans will adapt to starflight, discussed here yesterday, offer plenty of ground for speculation and good science fiction. After all, the path ahead forks in many directions, one of them being the continuing development of artificial intelligence to the point where ‘artilects’ rather than humans become the logical crew for star missions. If decades or even centuries are needed to cross to another system, then this gets around the problem of keeping people sane and cooperating across what might be generations of voyaging.
Another fork is biological, with humans being gradually engineered to make them more adaptable to environments they’ll find at their destination. Here we can imagine crews sent out in some kind of deep hibernation, their biology tweaked to allow a ready transition to the new planet. Or perhaps cyborg solutions suggest themselves, with humans augmented by digital technologies to deal with problems and interface directly with critical shipboard computer systems.
I always think of Freeman Dyson when speculating about these things because back in 1985, he lectured in Aberdeen on a one kilogram deep space probe that would be as much biological as mechanical, a genetically engineered symbiosis of animal, plant and electronics. Dyson saw the animal component as providing sensors and nerves and muscles for basic operations and navigation, while electronics dealt with communications and data return. The plant component offered a closed-cycle biochemistry fed by sunlight. Artificial intelligence would integrate all operations in a probe he described as ‘agile as a hummingbird, with a brain weighing no more than a gram.’
You can read about the concept in Dyson’s Infinite in All Directions (Harper & Row, 1988), and you might pair it with Anders Hansson’s paper “Towards Living Spacecraft,” which ran in the Journal of the British Interplanetary Society in 1996. In the same Starship Century volume as the Martin Rees essay is Dyson’s latest thinking on the matter, a lively piece called “Noah’s Ark Eggs and Viviparous Plants.” Like Rees, Dyson is captivated with the tools that molecular biology is giving us and sees them as a way to seed the universe with life, turning inhospitable venues into living worlds [video].
After all, we are now learning the language of the genome and have sequenced the genomes of several thousand species. As the speed of such sequencing increases and the costs decline, it will take no more than twenty years or so to sequence the genomes of all species now existing on our planet. It turns out that describing the entire biosphere does not take up all that much space. In fact, Dyson writes, the information content of the biosphere genome comes to something on the order of one petabyte, which is less than the amount of data held by Google. “The biosphere genome,” he writes, “could be embodied in about a microgram of DNA, or in a small room full of computer memory disks.”
The larger vision here is that we can’t talk about permanent human settlement away from Earth unless we learn how to grow complete ecosystems in remote places. Here’s the concept:
It is not enough to have hotels for humans. We must establish permanent ecological communities including microbes and plants and animals, all adapted to survive in the local environment. The populations of the various species must be balanced so as to take care of each others’ needs as well as ours. Permanent human settlement away from Earth only makes sense if it is part of a bigger enterprise, the permanent expansion of life as a whole. The best way to build human habitats is to prepare the ground by building robust local ecologies. After life has established itself with grass and trees, herbivores and carnivores, bacteria and viruses, humans can arrive and build homes in a friendly environment. There is no future for humans tramping around in clumsy spacesuits on lifeless landscapes of dust and ice.
But Dyson doesn’t stop at the kind of worlds we would consider suitable for humans. He’s talking about going well beyond this, designing biosphere populations that can survive in environments ranging from planetary moons to comets. He imagines future bioengineers designing biosphere genomes for such places (these are the Noah’s Ark Eggs of his title) and seeding them in venues like the outer Solar System, where warm-blooded plants that can collect energy from sunlight would begin the process of building an ecosystem. Many biospheres would fail but those that survived would evolve in unpredictable ways as they adapt to small, cold places without atmospheres. You can see that Dyson’s emphasis is on life at large, not just humans.
How would you engineer a warm-blooded plant? Dyson thinks even objects as distant as the Kuiper Belt could become homes for life if we can do something like this:
Two external structures make warm-blooded plants possible, a greenhouse and a mirror. The greenhouse is an insulating shell protecting the warm interior from the cold outside, with a semi-transparent window allowing sunlight or starlight to come in but preventing heat radiation from going out. The mirror is an optical reflector or system of reflectors in the cold region outside the greenhouse, concentrating sunlight or starlight from a wide area onto the window. Inside the greenhouse are the normal structures of a terrestrial plant, leaves using the energy of incoming light for photosynthesis, and roots reaching down into the icy ground to find nutrient minerals.
Comets have plentiful sources of carbon and oxygen along with nitrogen and other key elements. Sunlight at a distance of 100 AU is reduced by a factor of ten thousand, but even the human eye can concentrate incoming light onto a spot on the retina by a factor larger than a million. So Dyson is arguing that a mirror as precise as a human eye could keep a plant warm at distances even further out than the Kuiper Belt. These self-grown mirrors would, like sunflowers, track the Sun as it moves across the sky. Plants like these would also be viviparous, with the seeds developing into viable plants before being dispersed into the frigid waste around them.
Stop being provincial, Dyson is telling us: Instead of focusing on how to find or re-create exactly Earth-like conditions wherever you go, think about helping life itself to spread into environments where it does not now exist. Give life this chance and let evolution take over to lead where it will. Seeding the universe may lead to places utterly incapable of supporting people like us, but extend the tools of molecular biology far enough and the explorers of the far future may adapt themselves to the environments they have shaped. ‘A terrible beauty is born,’ Yeats once wrote about a different kind of transformation, but in that beauty may lie habitats for new beginnings.
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A good summary of Dyson’s perspective. He thinks we should plan on using the resources in the Oort cloud to aid interstellar exploration. Certainly this may seem useful in the FOCUS experiments, when we deploy antennas that can use gravitational lensing.
His ideas on cold, hard vacuum life he sketched out detail in some earlier talks, too. I was intrigued, and used them in a story that imagines how we might find such in future resource gathering:
In fact, there are ways astronomers could search for such life now, looking straight out from the sun and catching the back-reflection of the mirrors clustered around living greenhouses. Dyson calculates this, too.
Between Dyson’s chapter and Rees’, it looks like I’ll have some reading to do in Starship Century. Happily, I went for the Starship Congress Kickstarter tier which came with a copy!
Both of these topics are related to the Xrisk 101 session I’ll be presenting, but Dyson’s idea of dispersed habitats is a direct tie-in with my thoughts on long term preservation of the cultural and biological records and the Vessel project I’ll update on.
As is his way, though, Dyson is going a step further here: his idea that living and evolving caches could seed a vast and fertile future is wonderful. Hugely inspiring. I look forward to reading and digesting his chapter.
Should be some wonderful food for thought in store for us in Dallas!
We should be able to package enough DNA into customized spores that could spread by themselves. Spores are practically solid state and therefore low density…but their surface charge density is very high. I think this Zeta potential is sufficient for a planet with a moderate magnetic field to boost them into space. Some might be blown away in the the stellar wind.
I suppose even if a spore were captured by another planet’s gravity, tiny though it may be, it would accelerate just like any falling object and burn up in the atmosphere.
But as I write this I’m reminded of , was it Szilard, who said “Mediocre scientists should be paid not to do science.” I’m still waiting for that check.
This opens an entirely new reason to get off this planet – biological research and creation. I would argue that one of the greatest things stopping truly groundbreaking developments in understanding, designing, and extrapolating the current biological species, and by extension their eco-systems, is lab space. Completely separate and unhindered by regulation, inhibition, and -well oversight (even ethics, i suppose). Imagine LEO, the moon surface, the inside of asteroids, the surfaces of planets within the solar system, and even beyond as huge collections of self-enclosed playpens/ labs for developing and co-existing with new species from the tiniest virus to the most complex multi-habitat super-eco-system. It is so easy to view outer space as a place to exploit asteroids, planets or stars when we find them, or as the emptiness to travel through to get somewhere, but what about the emptiness itself as a testing ground for all things biological. It is the ultimate clean room and likely activist-free. Frankensteins for as far as the eye can see without the inconvenience of rioting villagers. The wild west, but wilder for risk-free creation – many of which will likely guide and support biology for travel and destinations beyond. Though, I am not sure how non-earth-gravity and micro-gravity systems adapt or scale-up or are even useful as analogs. PS: I am not a mad-scientist kook – i only play one on interesting blogs such as this ;)
Though, i do pine (in advance) for the time when ‘authentic’ unmodified species/ eco-systems become inefficient, obsolete, and ancient anachronisms – studied and valued by collectors, academics, and enthusiasts only – if architecture, domesticated species, and other victims of progress are any indication of our value system. Forget not that technology is not only a creator but also, by indirect action, a unintentional destroyer by attrition.
That being said: imagine non-earth objects as an ideal self-contained volume to store, preserve, and study such old-fashioned species and their habitats – interplanetary space zoos, anyone?
There are plants that can raise their temperatures above ambient using their own metabolism. thermogenic plants Something to start with.
It would be interesting to see how the greenhouse with external mirror could work. I tend to think that the mirror might be better inside the greenhouse, unless it is just a reflective ice surface. However the Haleakalā silversword has very reflective leaf surfaces.
The sort of features required, transparent membranes and silvered surfaces are much more common in the animal kingdom. Perhaps we need to start with animals that have symbiotic algae, rather than plants?
Thinking on this a bit more, what delights me about Dyson’s idea here is that, as an answer to Fermi, it’s quite comprehensive.
If Fermi was onto something, then we’ll have done our part to nudge the board towards radiant life. If we’re simply blind to an existing abundance, then we’ll be adding our drop to an ocean. And no harm in that.
Terrarium ships? Panspermia: The Kickstarter? The mind boggles.
How would you engineer a warm-blooded plant? Dyson thinks even objects as distant as the Kuiper Belt could become homes for life if we can do something like this:
I’m pretty sure ‘Greenfly’ is an Alastair Reynolds reference. Which novel does it appear in? Have read maybe half of Reynolds but I don’t remember the source on Greenfly.
Greenfly is the “rogue” terraforming agent that appears at the end of “Absolution Gap” as well as the short story “Galactic North”. Like myself, Alastair Reynolds appears to have an interest in self-replication and exponential growth. Such technologies will be necessary to realize effective space settlement.
Looks like I better order “Starship Century.” Amazing ideas. Reminds me a bit of K.S. Robinson’s “2312” in terms of ecosystem engineering, albeit mostly on moons and inside asteroids and scaled for biological humans in KSR’s world. There’s also a transition to AI and hybrid forms with his “qubes” and a lot of human genetic engineering to adapt to environments, including the “smalls” (tiny humans need less of everything). And of course a lot of social engineering with thousands of asteroid-based terrarium worlds for every interest and orientation.
Some of the scenarios mentioned here sound like “Invasion of the Body Snatchers” for the worlds on the receiving end.
We should not alter worlds with existing life or the potential of producing life of their own. Even then we may by chance annihilate something that we haven’t even imagined. What we destroy may be far more precious and interesting than what we create. Does anyone here think the Earth is ecologically better as a result of our activities?
The universe has plenty of space for us. We shouldn’t take the space already occupied (even potentially) by other beings.
“helping life itself to spread into environments where it does not now exist. Give life this chance and let evolution take over to lead where it will. Seeding the universe may lead to places utterly incapable of supporting people like us, but extend the tools of molecular biology far enough and the explorers of the far future may adapt themselves to the environments they have shaped.”
I just love this paragraph, it says it all, particularly the concept of ‘seeding life’ on other worlds.
Is there already an accepted scientific term for this? I mean similar to, e.g., the concept of terraforming? But seeding (genetically adapted) life goed beyond mere terraforming.
If there isn’t yet, such a term should be invented.
That latter one is hard to define and would pretty much force us to stay home entirely. Good luck enforcing it!
Re potential life, I was thinking in terms of something like the pre-biotic Earth. Hopefully by the time we’re able to ‘seed’ other planets we also have the scientific knowledge to recognize this type of world.
Further to NS and Eniac with regard to respect for already inhabited worlds: maybe a reconciliation of views is possible by selecting worlds for terraforming and ‘terra-seeding’ (my own provisional term) that are in an advanced enough stage to have indigenous life, but do not have it, in other words, they have had there chances but for some reason not used them.
Added advantage is the fact that a planet and its star need to be sufficiently old to be (most) suitable for settling.
Life on earth arose quite soon after circumstances became suitable, probably within a few hundred million years.
And if this approach leaves insufficient nearby target planets to choose from (i.e. all potentially suitable planets are inhabited), a more lenient approach could be chosen by selecting only planets with primitive (bacterial) life, leaving those with higher life intact.
My expectation is that there will be plenty of suitable planets without life and plenty more with only primitive life, and that higher life will be relatively rare.
Further to my previous comment, a very interesting future research approach to determine the age (and/or stage) at which a (terrestrial) planet gives rise to life, might be to collect biosignatures of (terrestrial) planets near relatively young (solar type) stars, such as Epsilon Eridani, 58 Eridani, HD 4391, HD 147513, 61 Ursae Majoris, Chi1 Orionis, V538 Aurigae, all solar type stars under 1.5 Gy old (and within 50 ly).