This episode is sponsored by Brilliant Science fiction and fantasy loves to show us brave archeologists and tomb raiders uncovering some ancient ruins of a lost civilization, but one day there might be whole civilizations devoted to it. One of the most popular plots in science fiction
is where our brave adventures encounter a ruined ship, typically of some ancient and
long dead alien race, or xeno-archeologists hunting among such ruins. These make for great stories, but lack an
element of realism in the context of the Fermi Paradox and Galaxy-spanning civilizations. You need some serious handwaves or plot contrivances
to explain not why a ship got abandoned or planetary civilization fell or went extinct,
but why nobody else found it or re-settled such a world almost immediately on astronomical
timelines. Analogies to our own lost ships and civilizations
don’t really work out well in space or by the capabilities of spacefaring civilizations. These days when a ship sinks we know where
and can go hunt that thing down, our ancestors couldn’t go SCUBA diving to reclaim their
lost treasures. We also want to keep in mind that a lot of
the archeological past is either composed of trash our ancestors didn’t care about
or repurposed, like using broken pottery in following rounds of construction and repair,
or had cultural or religious significance. We don’t find abandoned tracts of useful
land, just abandoned tombs or temples and the like, and typically ones subject to many
rounds of ravaging or repair or reuse or robbery. That’s not likely to happen to an entire
planet, unless it’s been subjected to such destruction that ruins probably wouldn’t
exist, or was the only one some civilization had, in which case it would imply they aren’t
overflowing with advanced technologies by the standards of any civilization able to
get there and dig it up. If you’re able to launch expeditions to
investigate worlds around alien suns, it means you have the technology to reach and colonize
those worlds too, meaning if you find a world with a dead civilization on it, it either
was very primitive compared to you or had a very stay-at-home attitude to the galaxy,
as otherwise one if its other colonies would come by and reclaim that world. You’re also not likely to have planets used
as waste dumps, to any high-energy civilization, throwing garbage down on a planet instead
of recycling that garbage or dismantling that planet for raw material is like throwing money
into a trash can and setting it on fire, except that your trash can is also made out of gold. If you’re settling other worlds it’s because
you have very good automation or very good energy production, and probably both, and
your bottleneck is always raw materials. This would seem to really mess up this popular
fictional trope, but another area where authors often mess up in science fiction is scale,
not just of how vast and huge our galaxy and the civilizations in it would tend to be,
occupying huge amounts of space, but also of time. And that revives this notion of ruins and
derelicts and trash planets and the folks who explore them for fun and profit. A couple weeks back we were looking at how
we might go about maintaining all the vast megastructures we hope to one day fill the
solar system with, and eventually even the galaxy. We’d expect to build trillions of them throughout
just our own solar system, as we move toward building a Dyson Swarm and becoming Kardashev-2
civilization. I noted there that even if we’re incredibly
good at maintaining those structures, in many cases they would end up wearing down and get
abandoned, destined to float around until they get recycled. Even if they lasted as long as our own civilization
has, call it ten thousand years, and only spent a decade abandoned and scrapped, that
would still mean one in a thousand would at any given moment be sitting there as a derelict. And mind you, that’s a way better reclamation
rate than we have in our civilization, where a lot more than one in a thousand structures
is sitting around vacant and nominally abandoned, or occupied by squatters. Such being the case, these sort of megastructures,
each meant to be home to hundreds of thousands if not millions or far more, and themselves
numbering in the trillions, would represent the equivalent land area of a million Earths,
just in this solar system alone. They’re a small fraction of a vaster civilization
that dwarfs them, but are just so numerous that they dwarf us. Even if these decommissioned space habitats
and industrial megastructures were only a thousandth of their civilization, and even
if they only supported populations of hold outs, squatters, or scavengers a thousandth
of our own population density, you’d still be talking about many trillions of people
in any given fully developed, Kardashev-2 civilization. And that’s just assuming long-lived well-maintained
habitats being only briefly out of play before being recycled in some fashion. It doesn’t include the countless quadrillions
of ships probably meandering around that solar system or scenarios like one being abandoned
for reasons like a war, an economic or fashion shift, or repurposed because its inhabitants
or maintenance AI went a bit weird in the head. Such places could easily just age out, not
from maintenance issues, but because in a long-lived civilization with life extension,
they might fill up quick and be left with nominal immortals. Those folks wouldn’t last forever, they
might die or transition to a digital existence, uploading their mind, and their neighbors
who have known them for centuries might want to effectively entomb them and their way of
life rather than give that home and parcel of land to someone else. The same could happen on Earth, as we noted
in “Civilizations at the End of Time: Dying Earth”, when building on a planet you don’t
have space issues, you have energy and heat removal issues, so a culture with strong building
materials and automated maintenance might be prone to just powering down someone’s
home and building over top of it in endless layers, a rising planet-wide city or Ecumenopolis,
a Kardashev-1 Civilization. They don’t really care about their possessions
much, as a raw material source, because it’s not going anywhere, and they might not even
know if someone actually died or just uploaded their mind or went on ice for some centuries
out of boredom. Unpowered facilities don’t really count
to them, only those drawing a lot of energy and producing a lot of heat matter. Given a few million years, even if people
tended to live thousands of years on average, that planet is going to be more necropolis
than ecumenopolis. Same, if some habitat gets grey-gooed or overwhelmed
by some killer AI or super-virus, it’s as likely to be quarantined as blown up. Even if you opt for that route with it, or
recycle your abandoned habitats, you still need to drag that off somewhere safe if you
can, plus a full-blown Kardashev-2 civilization has that same waste heat issue an Ecumenpolis
has, plus the debris issue. You don’t nuke a dangerous or derelict megastructure
in the middle of the Swarm if you can avoid it, you give a push outside the main swarm
to a place where it represents no navigational hazards or heat production limits or a vacant
and valuable lot in your solar englobement. And they are quite likely to be towed off
to some facility that specializes in handling the wrecks, or storing them till they can
be handled, those could easily begin to resemble the classic Space Hulk of lumped-together
stations and ships, scrapyards of astronomical proportions, and such a storage facility might
be a minor planet too, since it’s nice to have just enough gravity to keep your debris
from floating away. Probably some mined-out asteroid or moon that
had all its smelting facilities still but nobody particularly wanted to settle in a
big way. Indeed, much as communities often invite landfills
or prisons into their backyard for the extra jobs and funds, while far more are happy not
to have them in their own backyard, places fallen on harder times might fight to become
such repositories. When we start looking at the sheer numbers
involved, even if we are ultra-conservative and optimistic about it, it’s not that these
things are the norm, it’s just that they are outliers of such an enormously massive
sample that they are everywhere. This is a bit of a recurring concept in our
Rogue Civilization series, that many of these less than utopian staples of science fiction
could pop up as phases places go through or simply be so numerous by the sheer size of
the main civilization that even though they are rare, they still outnumber our own modern
civilization many times over. One quick note on this waste heat idea, and
the notion of time. Assuming you are still bound by the Laws of
Thermodynamics, you can never use more power than you can get rid of as heat, and this
places a lot of constraints on many of the projects we discuss here that tend to get
overlooked and why I so often pound the drum about waste heat as the bottleneck on advanced
civilizations. Ultimately heat can only be gotten rid of
by radiating it away, which is based on your total surface area and your temperature. You can spread out to allow you to use more
heat, but for something like a Dyson Swarm this means longer and longer travel times
and signal lag not only over the whole thing, but between individual components. Volume rises with the cube of radius or diameter,
surface area only with the square, that results in an inverse relationship between population
and density, because a civilization a hundred times more numerous in terms of energy use
needs a hundred times the surface area to radiate that heat away, meaning it is ten
times wider and thousand times larger in volume. Everybody has ten times more space, meaning
they are the cube root of 10, 2.15, times further away from each other than before. Every signal takes 215% as long to arrive,
every trip takes longer or requires more energy, and thus more heat, and those signals, even
if as concentrated beams, need a bit more power to deliver their message, and thus more
heat. It also means you don’t really want people
smelting down a habitat in a grand display of energy wealth right in the middle of that
swarm, nor do you want to push it out of that swarm really fast, because heat is money in
these places, not energy. But this has another aspect too, because you
can’t expand a planet to increase how much it can radiate, so if you’re trying to disassemble
a planet for raw materials or terraform it with nanotech, there is actually a maximum
speed you can do this at or you’ll smelt all your equipment or little robots or terraformed
organic material. It’s just an aspect of high-tech civilizations,
even ones we’d think of as post-scarcity, waste not, want not, especially when it comes
to using energy inside the main portion of a built-up civilization. As another quick note, you might wonder, considering
how much energy is involved with moving things at interplanetary speeds, if they might find
smelting something down inside the swarm energy cheaper than shoving it away, but they can
reclaim most of that energy used to push it up to speed away from them, and such derelicts
also make a handy place to adjust habitat orbital paths with, by pushing off them, using
the various beaming or mass driver techniques we’ve discussed elsewhere. So long as they can push the habitat away
using less net heat than smelting it there would take, they will shove it away, and slowly,
so its voyage may take many years. So we’ve got all these derelict ships, ghost
town habitats, and all these abandoned layers of Ecumenopolises that might be sitting around
not in use by the main civilization for any number of reasons. A given world might not do that Necropolis
approach we mentioned of course, indeed I’d not expect most would, but there’d be many
such places and on some you’d probably have teams of people who hunted around them. Legally or not, a world might have some rule
that if no one heard from the owner in a century they’re allowed to pry the place open or
auction the rights off to pay back taxes, like we often do with homes or storage units. Such things would vary from world to world,
and it might be very rare and orderly, or it could be a totally illegal black market
thing. It might attract romantic adventurers or scoundrels,
it might be some small club of bored dilettantes or some university-style archeology department. And remember time here too, if you’ve had
some isolationist habitat that utterly closed up its shutters and ran on reserves of fusion
fuel and raw material, as they likely all could do, it might finally go dark hundreds
of centuries later and when you crack that open you might find layers of ruins and fossils
and inhabitants at the end who looked like morlocks and were effectively an alien civilization
right in your own backyard. Same, we’ve often talked about generation
ships meant to plow through interstellar space for centuries, or even hundreds of centuries,
and if one got abandoned or damaged, or left behind a colony in its wake that just didn’t
take off, someone is eventually going to want to investigate that matter. This isn’t like poking around one small
tomb or one wrecked ocean going ship, these things are huge and old and could occupy whole
towns worth of experts for generations dissecting what happened. And you probably need to move slow about that
too, odds are their data is encrypted and trying to find the 3M post-it note someone
conveniently left on their terminal with their password might take a while, or you might
be negotiating with some half-mad ship computer for access, only to find out that it went
nuts at failing to save its crew from a space debris collision and later find out in truth
it had also wiped out the handful of survivors in a berserk attempt to cover its shame. You might get some fairly crazy crew on board
a lot of these ships too. If you’ve been one of skeleton crew running
a ship for generations it’s not hard to imagine getting a bit neurotic, or having
been, to have signed on for such a job in the first place, and that ship might be brimming
with weird traps, hidden vaults, killer robots, feral pets or genetically tailored maintenance
organisms, or some axe-crazy lunatic who murdered the other crew and went on ice to await fresh
victims to add to his skull pile. You send a team in there looking for information
or treasure, and you might find you bit off more than you can chew, like they kept gene-hacked
or cyborged animals around for pit fights and the ultra-redundant interstellar space
freighter has still got life support running partially millennia after the dozen crewmembers,
or even lone crewmember, died somehow. In Warhammer 40k, a setting notorious for
its utter disinterest in scientific realism that still somehow manages to nail many ideas
more realistically than most scifi, they have folks forever boarding derelict ships and
spacehulks or abandoned lower layers of Hive cities and running into mutants and aliens
or leftover ancient and crazy technology, that might occasionally happen in the future
when folks go in to investigate or loot such places. Not just plunder for artifacts or memorabilia,
you might have insurance investigators poking around for years figuring out what happened
and salvage teams dragging them back to holding yards where they might take centuries to arrive
and as long to get processed through a court for who owned this or that or was liable for
what. You could easily have an underfunded storage
yard of derelict ships or habitats under lockdown while they waited for the courts to settle
the case, which might take centuries even if they were expeditious just from many of
the litigants not living in the same star system. That’s quite an opportunity for anyone shady
too, both to occupy those places or take a bribe to look the other way or to deal in
goods looted or produced in such places. We’ll save space piracy for another time,
like quietly invading some isolationist and primitivist habitat to use as a base, but
any place where the rule isn’t finders-keepers on salvage, there’s likely to be that long
drawn out investigation period and given the potentially ultra-hazardous junk inside, even
when the authorities do investigate it’s likely to be slow and super-cautious. If your job is to go in and investigate such
places, filled with potential death-traps of automated defenses or broken bits, you
might be quite glad to look the other way as a silent partner to some team of illicit
scavengers seeking treasure and excitement, who will deal with most of the hazards themselves
and give you a cut of the plunder, if they live. For that matter, for every habitat being decommissioned
there’s going to be a period where most folks don’t want to live there anymore but
it’s still rather habitable. That’s very ideal for squatters and rogues,
and the nominal owner or oversight authority might actually be inclined to turn a blind
eye as a disreputable crowd of squatters or looters might encourage those folks still
stubbornly living there to vacate so they can turn off the lights and bust it down for
salvage. Or, if it follows that notion of inhabitants
slowly aging and going digital at some point, living in the data cores of the megastructure,
they might encourage that so they can divert the energy and resources to more computing. They might be the ones pushing for an exodus
too, trying to turn the place into a ghost town in a very literal sense, or the maintenance
AI might be wanting to turn the place into a nature preserve to protect the increasingly
divergent mutated organisms living there. So much depends on the psychology and society
of that civilization, and it’s likely to vary all over the place, in both space and
time. In the inner core of a Dyson Swarm you’ve
got that energy and heat issue but everybody is pretty self-contained and self-sufficient
if they want to be, so that offers a lot of room for divergent cultures, outlooks, and
so on. But you’re also likely have millions of
Oort Cloud Habitats built by isolationists or as part of border fort and detection system
or laser-highway relays, and you could have whole migrant fleets that meandered around
those raiding abandoned facilities or squatting in one relegated to neutral status in some
border dispute between two neighboring powers. You’d have failed colonies, abandoned stations,
derelict ships, scrapyards for equipment or dangerous material, old military hardware
floating about, facilities or ships scuppered by their owners or captains for the insurance
money or to get out of some obligation. Probably not a lot proportionally, especially
in the sort of utopian society we might hope for, ethical, prosperous, and smart, but enough
in raw numbers to have whole civilizations worth of people on the fringes engaged in
salvage, plunder, or squatting, and even if entirely inside the law, whole facilities
devoted to it with staffs big enough and operational times long enough to become their own unique
culture. You could easily have some abandoned asteroid
mine turned scrapyard peopled by millions whose whole economy for centuries was taking
apart dead megastructures towed there, and that’s likely to be a fairly unique sort
of place. Same for some settlers coming to a world or
habitat that was abandoned or failed halfway done or transitioned to some digital existence,
living in the shadow of that prior civilization with it influencing you, all the way down
to sneaking around the old dome or subterranean colonial facilities with your childhood friends
looking for knick-knacks left by them or by prior generations who set up their clubhouses
there. For that matter, if everyone did go digital,
they might have whole layers of virtual worlds in those abandoned ghost towns you might be
exploring too. And again, time and divergence mean that whoever
was there first and whoever is there now could be so different from each other they might
as well be aliens. So maybe we never get to experience the classic
science fiction scenario of breaking into alien spaceships to find high-tech artifacts
guarded by murderous aliens or xeno-archeologists cracking open the tombs of fallen civilizations
on dead and sterile worlds sitting for millions of years, but we might end up getting a very
close approximation. I’m not sure if that would be a good thing,
but at least it would be exciting. One of the points I was emphasizing today
was how things like astronomical scales and thermodynamics can place limitations on even
very advanced civilizations or make entire civilizations where we’d normally expect
just a few folks as outliers. These often get missed in science fiction
even by authors who are pretty good about doing their research and knowing their science,
and sadly many don’t. But a good understanding of math and science
is what lets us try to look at the future in a more realistic way, be it the far future
of humanity or just our daily lives and careers nowadays. It’s an area of knowledge whose usefulness
cannot be overestimated, something I suspect anyone watching this show needs little convincing
about. If you want to learn more math and science,
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challenges in the archives and access dozens of problem solving courses. So we mentioned how all these derelict ships
and stations and worlds might offer some excitement in the future, where we’d generally expect
things to be pretty prosperous but maybe a bit boring, and while there are a lot of ways
we might amuse ourselves in the future, one I get asked to cover a lot is what sports
will be like in the future and in space, and next week we’ll take a look at what sort
of new options low or zero gravity can offer us for our athletes and audiences in Space
Sports. The week after that, we’ll return to Mars
to look at how we’d go about terraforming it if we wanted to, in Springtime on Mars. For alerts when those and other episodes come
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have a Great Week!
Issac, have you done a video on the future of Recycling? We could technically recycle matter down to the atomic level, if we put the resources into it. What sort of technologies could we deploy to clean up the environment, and make sure that nothing goes to waste?
The space station at the 4:53 mark is terrible. People inside the rings would be subjected to continuously shifting pseudogravity, and the bearings the rings are mounted on would suffer huge torques all the time from gyroscopic effects.
Perfect background for a video titled "trash worlds", though. :)
First thought on seeing the title: the scene with the Junkions and the Planet of Junk, from The Transformers: the Movie, as an example of a "trash world".
related:
https://www.reddit.com/r/ImaginaryDerelicts/
https://www.reddit.com/r/ImaginaryRuins/
You could probably do a whole episode just on dealing with waste heat.