Time Justice Part Deux: 5.25 x 10²⁵ Puppies
A Bright Future for Humanity
This is part 2 of a three article series. The first one discusses and justifies Toby Ord’s estimate that the human race has about a 1 in 6 chance of destroying itself in the next 100 years (a large portion of that article is functionally a summary of his book “The Precipice”). This one will cover what the future might look like if we don’t, and explains why (and how) that risk is likely to decline. The third will introduce the beginnings of a framework for “time justice” as a way of conceptualizing how the conclusions of the first two parts should influence personal and public decision making in the present.
How Many Puppies Survive? 5.25 x 10²⁵, or 0
Why are we talking about puppies? Contrary to my own personal beliefs, many folks are surprisingly ambivalent about humanity’s survival. But, even anarcho-primitivist death cultists care about puppies.
So, rather than discuss solely how to save humanity, let us discuss puppies.
Without the intervention of humanity, puppies are likely to exist for about another 1 million years (the rough average for how long a mammalian species survives). As a hard cap for the longevity of the species, they will almost definitely die out in 1–2 billion years as the earth becomes uninhabitable due to the expansion of the sun. At an extremely hard cap, they will die out in around 7.5 billion years when the earth is swallowed by the sun.
If, on the other hand, humanity becomes multi-planetary, and then multi-stellar, this move will save not only humanity, but any segments of the earth’s biome that we bring with us. We’ve never populated new places without bringing our own favorite species along — both intentionally and unintentionally (for better or for worse), and it’s unlikely we’ll start now. In fact, given that most of the places we would go inhabit are lifeless and therefore unsuited to sustained human life unless we bring our own biome with us, we will nearly definitely do so.
In this alternative world of human interstellar expansion, along with many billions of human generations that can outlive the earth, we could expect to allow for the existence of many billions of generations of puppies with somewhere around 5.25 x 10²⁵ puppies in those generations.
This number comes from taking the current number of dogs on earth (900 million), dividing it by 1000 as a population for each planet we inhabit (to account for the fact that we will in many cases only inhabit a fraction of a planet’s surface), multiplying it by a humble estimate of 5 billion rocky planets in habitable zones in our own galaxy, and then multiplying that by 20 billion galaxies that constitute our likely hard limit of expansion (due to the constraints of the “reachable” universe — also even that, it turns out, is potentially hackable).
Yes, that’s 52,500,000,000,000,000,000,000,000 puppies. I think.
Hard to get the number of zeroes right….
So whether, like me, you care a lot about humanity surviving, or you just want there to continue to be puppies in the future, we are all on board at this point that humanity outliving the earth sounds like a pretty appealing option. Is it realistic? Let’s discuss.
Good News or Bad News First?
Let’s start with the bad news. We likely do not have a billion years, or even a million years, to figure out how to become interplanetary and interstellar (thereby saving ourselves and the puppies). Per the first article in this series, we are roughly playing a game of Russian Roulette with our own extinction (a 1 in 6 chance of losing our ability to save ourselves) every century. Every one hundred years, as things stand now, we pull the trigger and another chamber clicks.
The good news is that while diversification works against us so long as we are on one planet (we need to independently win the ⅚ chance of survival every century to not die), it works for us once we are on 2+ planets, in the sense that humanity only goes extinct if the less probable situation of our extinction happens on both or all of our inhabited planets. There are a number of reason why probabilities of survival on any newly settled planets might vary, but for the sake of simplicity we can start by assuming our probability of surviving on each new planet is basically the same as our probability here, and see how diversification seems to save us as we get more uncorrelated self sustained human populations on planets. I mean, look at that!
Even if we lower the survival probabilities of any non-earth settlement to a coin flip (50–50 chance), diversification still quickly improves our odds (below). I’ll add a 5 and ten planet option for this one!
This means that if we can successfully become multiplanetary, and multi-stellar, the bottleneck we are experiencing is temporary. To abuse the metaphor, the bottleneck is narrow but also short. Like a Bundaberg Ginger Beer bottle. Or a carboy. Or a Red Stripe. Maybe like an hour glass. Whatever, you get the point.
Which means our keystone question is whether interplanetary and interstellar expansion is feasible — or, even possible. Especially, you know, before we die.
The answer is a resounding yes.
Breaking Down The “Inhabit the Entire Known Universe” Problem
As it turns out, we are extremely lucky. The situation we have found ourselves in is rather like a video game, or a Shonen anime story line, where we have little mini-bosses that (if we defeat them) give us exactly the techniques we need to defeat the big boss (and maybe even learn something about ourselves along the way). Let’s take this from the top end of the ladder to the bottom.
Going from galactic to inter-galactic is actually pretty easy. For one, we’ll have many billions of years to figure it out once we have spread across the milky way (and we will have become nearly impossible to kill off). Beyond that, our galaxy is in a group of nearby galaxies (the local group). The closest one is the Andromeda galaxy — which is already cruising towards us and will collide with the milky way and form a giant elliptical galaxy in about four billion years. This will more than double the number of stars available for settlement in our galaxy. In the next 100 billion years, all the galaxies in the local cluster will merge together into one big galaxy. So, actually, all we have to do to populate the entire local group of galaxies is survive. They’ll come to us.
Going from interstellar to galactic is actually also surprisingly easy. Below is a rendering of our stellar neighborhood.
If you’re strangely well in tune with the direction I’m going with this, you’ll notice something. They seem pretty evenly/randomly distributed. And, as it turns out, they are — which is fantastic news. The relatively uniform scattering means that if we can make it to 1 star, and make a self-sustaining settlement there, which in turn can send out another settlement ship, we can exponentially expand to new stars.
Think of an archipelago and a primitive sea-faring civilization that can travel only up to 6 miles on open seas. But, in six mile jumps from island to island, the seafaring civilization can spread throughout the whole archipelago. They don’t need to be able to cross vast oceans: the archipelago is spread so they only need to be able to sail six miles! If you’ve ever played the Civilization games (I’m partial to Civ IV) this is extremely relatable. What you end up seeing in a situation like this is that as soon as someone figures out how to reach the next island, the entire archipelago is quickly inhabited.
“6 miles” wasn’t an entirely random number here, as it turns out that if we can replicably populate a star that is 6 light years away, we can populate very nearly every star in our galaxy. And, even if we’re going at 1% the speed of light, and each new settlement took 1000 years to be able to send out it’s own new settlement ship to the next star, we’d populate the entire galaxy in under 100 million years.
(Note here, according to my spell-check “replicably” isn’t a word. Well, it is now.)
But every journey begins with a step. As it turns out, we have a perfect candidate star just 4.3 light years away: Proxima Centauri. Even better, that star has a rocky planet (Proxima B) close enough to it to potentially have liquid water (although it likely kind of sucks, we’ll get to “building settlements on planets that suck” in a little bit). 4.3 light years sounds, still, pretty hard.
How close are we (technologically) to being able to make that journey?
Pretty damn close.
Interstellar Travel
Helios 2 was the fastest ever manmade object. It did a slingshot near the sun and got to speeds of around 240,000km/hr. Even this would take 19,000 years to reach Proxima Centauri. If we designed a “Generation Ship” (a ship built to allow multiple generations to survive on it during an interstellar trip), we would be spending liiiiike 600 generations of people living and dying on that ship. We won’t go much faster than this with traditional rocket fuel and gravitational slingshots. To get to Alpha Centauri in one lifetime we need to go somewhere in the area of 10% the speed of light.
Not ideal. That’s pretty fast. Rockets are cool, but not that cool.
Fortunately, we have better technology for interstellar travel that either exists now or is coming in the near future. To avoid burying the lede here, we will probably be able to send unmanned probes to Proxima Centauri in the next couple decades using solar sail technology (a la Starshot initiative), and could do a manned mission in the near future by making a spaceship that surfs nuclear blasts. But, let’s take a closer look at these and other technologies.
The Starshot initiative is an existing project that would use solar sails to get up to 20% the speed of light. Solar sails’ effectiveness for acceleration is a function of the strength of the “wind” (lasers) behind it, the size of the sail, and the weight of what is being carried (as well as, I guess, the material of the sail).
That bit about weight is why this won’t work so well for manned missions, but is viable for unmanned missions. In this project, tiny probes the size of a nickel will be put on solar sails, and we will just absolutely blast them with powerful lasers to accelerate them to this insane speed and send them shooting off toward Proxima Centauri to collect data, and send that data back home. These would take about 20 years from launch to get to Proxima Centauri, and another 4.3 years to send back the data. Not bad.
Before moving on to our best existing technology for manned missions, it’s worth noting that it probably isn’t impossible for us to use sails for manned missions. We’d just going to need a bigger laser. Like, a built on the moon and powered by Helium 3 nuclear reactors kind of laser.
Unfortunately, to date, we haven’t ever built a Helium 3 nuclear reactor on the moon. But you know what we have built? Nukes. Lots of nukes. When the world gives you the Cold War, you might as well make lemonade (is that how the saying goes?)
We could start making even more nukes now (and also a spaceship) and could send people off to Proxima Centauri this century. It’d be a little bit slow (could do it in about 90 years at 1G of acceleration), but it also doesn’t require any major technological innovation. We just make a lot of nukes, get them into space, and have our spaceship periodically set off nuclear bombs behind it. Crude, but effective.
If we want something a little more sexy/futuristic but that also might go faster we have the option of sustained fusion. We can’t do it yet, but we’re so close (admittedly we’ve been “so close” for a long time). This might be able to take us there, due to a much more efficient mass/energy conversion, at a nice clip of 10% of the speed of light.
Balancing whether to go with the sure-thing in the 2000s to 2100s of building a nuke-surfer spaceship versus trying to figure out sustained fusion ties into the quandary of the Wait Problem (which I would discuss here, but this article is long enough as is).
But, the point is, we can (and probably should) start working on this now.
A few honorable mentions on interstellar travel technology:
-Ion Propulsion (medium future tech): this is basically a way to more efficiently get a tiny amount of thrust for a really long time. Also check out inertial confinement fusion (small fuel pellets shot by lasers for tiny bits of fusion) used by example by the Ghost team project (and allows nicely for deceleration when approaching a star — this was for an unmanned mission).
-Antimatter Drives (hardcore future tech): this is the sexiest option. If you thought the 1% efficiency of mass to energy conversion from fusion was cool, wait until you see the 100% efficiency of antimatter drives. Unfortunately, antimatter is awfully hard to harvest and store…we’d need kilograms that we could keep on board instead of just the occasional tiny particles that rapidly disappear in our largest particle accelerators. This one is a stretch, to be honest, but if we got good at making and storing antimatter, then built Pion rockets, we could go like .5c and make the trip to Alpha Centauri in less than 10 years. If we got up to .8c, we’d really get some of that relativity effect, and astronauts would only experience the trip as being 3.3 years.
-Kugelblitz Drives or Alcubierre Drives (far future tech): These are super cool (powering a ship with a tiny black hole, and literally warping space-time for acceleration, respectively), just google them. There have been some very recent updates on the feasibility of Alcubierre Drives in particular.
OK, so we basically already have the tech to make the trip (first unmanned with solar sails, then manned with a nuclear stockpile that dwarves that of current nuclear powers), but what are we going to do when we get there and Proxima B sucks? It probably will suck. You know what else sucks? Mars.
Interplanetary Settlements: Mars Sucks
If you were on Mars, you would die in about a minute. Mars has only 0.6% of the earth’s atmosphere, which means that it has almost no greenhouse effect. The suns rays bounce right off, leaving the temperatures around a refreshing -60C. And, it lacks the atmospheric pressure of the earth, which means water (even ice) would sublimate immediately from to gas. Also, the lack of atmosphere means you aren’t protected from the bad stuff in the suns rays. The sun, to quote the history of the entire world, is a deadly laser.
Given that the “death ray in the sky,” “immediately freeze to death,” “what we’re mostly made of would turn to gas,” and “not being able to breathe” things are all related to not having an atmosphere — the obvious answer here is to just make an atmosphere.
Whelp, not so fast.
At the end of the day, if we can get a half decent atmosphere on Mars, we can terraform it. That solves the pressure problem, the temperature problem (both necessary for liquid water), and the radiation problem. How hard could that be? In fact, we know (thanks to our rovers) that mars was once a much warmer and wetter planet than it is today! All we need is to create major greenhouse gas effects and pump up those atmospheric numbers — in fact there’s a bunch of CO-2 lying around on Mars which will do that quite nicely.
Easier said than done.
The problem is that Mars is a lot smaller than the Earth. That means that it cooled much more quickly, freezing its core, eliminating its electromagnetic field, and allowing deadly lasers from the sun to blast it’s atmosphere into space (basically).
This presents a few problems.
The first is that not all the raw materials from its old atmosphere are still there — it’s not clear there is really enough CO-2 to create the atmosphere we need. We would need all the CO-2 from the south pole ice caps (which are layered water ice and CO-2 ice), a bunch of CO-2 from the surface of Mars (which would be released as it warmed), and then also a bunch more CO-2 from…..? Maybe mining carbonate rocks from Mars and somehow releasing CO-2 from them? Through electrolysis?
This is going to be pretty difficult and energy intensive (and there might not even be enough CO-2 on Mars to get it done). If somehow we did get it done, there is a fair amount of water in the Martian poles and an unknown amount of additional water locked in its crust that could become liquid (although probably not enough for, like, oceans).
A big down-side to this approach (besides it maybe not being possible) is that it also leaves us with a CO-2 based atmosphere….which would be poisonous. We could help that out with cyanobacteria, but that would be a slow process (and might leave the atmosphere still poisonous — although I guess wearing breathing masks is easier than wearing space suits).
It would be a lot easier if we could find a crap-ton of nitrogen rather than using CO-2.
Oh wait, the Kuiper belt is packed with comets that contain both nitrogen and water: let’s smash them into Mars.
This would take a while, but seems potentially to be a better solution.
But, even if we achieve that, we face a second problem resulting from Mars’ diminutive girth. If we managed to make a new atmosphere, it would get blown off into space by the sun’s deadly lasers again. It’s going to take us at least a little while (maybe centuries) to smash enough comets into Mars to create an atmosphere… so we will likely have some technical advancements for energy production by then? Kind of a weak approach. And, even so, I doubt we will have the capacity to re melt Mars’ core.
Maybe we will be able to place some kind of giant magnetic field generator in orbit between Mars and the sun? This seems like a lot. Over all, terraforming sounds probably not impossible, but also difficult and unlikely to be achieved before we kill ourselves.
But why terraform a whole planet? Why not just make a fun lil’ bubble.
Para-Terraforming Babyyyyy
I probably should have opened with this, but just creating a sustained base of operations on mars (likely helpful in any of these processes for actual self-sustained population) requires absolutely no technological advancement. To be clear: living their would suck. As it stands now, you’d probably be in airtight, confined spaces surrounded by a hostile environment with no windows relying entirely on energy delivered in shipments from earth in the form of nuclear fuel. This is the kind of thing you can make psychological-thriller sci-fi movies out of.
The actual theoretical constraints between that and terraforming mars are just that it takes so much material and so much energy to solve the atmospheric and magnetic problems. But, you can make the problem smaller and reduce those requirements. What if you just had to build extremely thick domes (thick enough to solve some of your radiation problems) and create and atmosphere in them.
Even if those domes cover 1/20th the surface of mars, your material needs are far less than 1/20th because they have roofs instead of open skies. All of a sudden, there is plenty of CO-2 and water in Mars’ ice caps alone to create a sufficiently pressurized environment and fill it up with liquid water!
What’s the point?
The point is this:
(1) Becoming a multiplanetary species is probably the highest impact thing we can do to ensure that known life (and intelligent life) does not end (and the only thing we can do to ensure it does not end with Earth).
(2) We have every reason to think doing so will be difficult, but no reason at all to believe it will be impossible.
(3) Therefore, we should do it.
