Could we ever colonize another Earthlike planet?

[caketastydelish]

"Earthlike planet" as in it has pretty much everything humans would need to survive, at least theoretically, without the use of a space suit.

It would have an ozone layer, comfortable temperatures for humans, water, similar atmosphere, similar gravity.

With literally countless planets in the universe (and the vast majority in our very own galaxy we are unaware of from my understanding) the odds of at least one of them we eventually discover meeting this description is pretty good.

Nothing we have right now could travel that far (especially carrying lots of humans), so this is out of the realm of possibility in the immediate future.

But let's say a) we have discovered such a planet b) we've figured out a way to travel there efficiently and reasonably quickly and could take literally millions of people if we wanted.

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What challenges would remain? Let's say the planet is littered with gigantic animals that would more or less be their equivalent of dinosaurs. Would modern technology be enough to make us consistently at the top of the food chain?

The bigger problem is disease. This new planet would almost certainly have a plethora of diseases/bacteria/etc that we have not been exposed to before. 90% of the Natives from the new world were wiped out when old worlders encountered them. Would we be devastating to the ecosystem there? Would the environment there kill our settlers? Would it go both ways? What other challenges would there be?

discuss

 

[El_Machinae]

I very much recommend the Isaac Arthur YouTube channel. I mean, I will eventually discuss but you are missing out on an absolute gold mine if you don't know about that channel

 

[uppi]

What challenges would remain? Let's say the planet is littered with gigantic animals that would more or less be their equivalent of dinosaurs. Would modern technology be enough to make us consistently at the top of the food chain?

If we assume those animals to be incapable of developing much technology of their own, I believe that humans would eventually win out. But the key word is "eventually". Until that state is reached there will be quite a lot of attrition and success would be determined whether the colony can stabilize itself before is succumbs to this attrition.

The bigger problem is disease. This new planet would almost certainly have a plethora of diseases/bacteria/etc that we have not been exposed to before. 90% of the Natives from the new world were wiped out when old worlders encountered them. Would we be devastating to the ecosystem there? Would the environment there kill our settlers? Would it go both ways? What other challenges would there be?

I don't think diseases will be a problem. A microorganism needs to have some adaption to its host to take advantage of the host. Alien diseases would be very unlikely to be compatible with human hosts and vice versa. A bigger problem might be toxic substances, which the local wildlife is adapted to but is deadly to humans (and the other way around: someone taking a dump might turn the spot into a wasteland)

 

[caketastydelish]

Then how can you explain how the European diseases wiped out so many of the Native Americans? In what way is this different?

 

[Imaus]

Then how can you explain how the European diseases wiped out so many of the Native Americans? In what way is this different?

The organisms shared the same host and biological structure overall? Human viruses lept from Human to Human. A xenobug might just bounce off or not even recognize human cells as palatable. We already live on a world where many diseases are species-specific, and while some jump, some don't. We have no idea if the lifeforms of another system are rooted in DNA, RNA, or could be something wholly different. Who knows what structures and forms xenolife might grow from?

 

[uppi]

Then how can you explain how the European diseases wiped out so many of the Native Americans? In what way is this different?

Europeans are humans,
Native Americans are humans,
alien dinosaurs are not humans.

 

[Lord Shadow]

Looks like this forum isn't very active, but since the topic's interesting, here goes.

The greatest challenge for space colonization is finding enough motivation to shoulder the monumental expense it'd require to develop the means for it. Even if we had a sufficiently Earth-like target within reach.

Short of a completely ground-breaking, paradigm-shifting black swan eureka event leading to the quick discovery of "easy" (read, not consuming a star's worth of energy) faster-than-light travel, of course.

An exodus-type scenario would be the most motivating for developing the means for interstellar transport of millions plus. But by the time such a scenario became apparent to enough major players, the question would be whether there's enough years left to develop the aforementioned solution.

Anyway, assuming that's all possible and viable and sensible, related to diseases, broaden the scope and think about the new planet's biosphere. Local bacteria and viruses aren't compatible with us, good; local food consumed by wildlife isn't compatible with us, bad! Before any serious settlement plan can be executed, intensive studying and gengineering would have to devise a way to either adapt local organics for human consumption, or adapt Terran crops/livestock to the new world. Or adapt colonists to be compatible with the alien biosphere, giving birth to a whole sub-branch of our species!

 

[Leifmk]

I don't think diseases will be a problem. A microorganism needs to have some adaption to its host to take advantage of the host. Alien diseases would be very unlikely to be compatible with human hosts and vice versa. A bigger problem might be toxic substances, which the local wildlife is adapted to but is deadly to humans (and the other way around: someone taking a dump might turn the spot into a wasteland)

I would be prepared, however, to believe that some alien organisms might decide that human bodies made a hospitable environment to colonize and grow in, even without being able to eat us or hijack our cells. And that our immune systems wouldn't have a useful response.

Toxic or allergenic substances, yeah.

 

[Lord Shadow]

Just like we'd have trouble adapting to an immiscible biosphere, I don't think alien organisms would find an environment in which they can't eat "hospitable".

Growth is impossible without some kind of energy consumption.

 

[Lord Shadow]

Our ancestors wiped out the mammoth and turned the aurochs into docile meat and milk factories without modern technology. Unless the aliens are sapient they won't be much of a problem.

Beyond the fact you're talking about largely peaceful herbivores and that mankind never quite went toe-to-toe with dinosaurs, it's difficult to predict the forms of alien life we might encounter. Peaceful or otherwise. We'd be unpalatable to predators, most likely, but there's no telling how might they react to our intrusion, territorially.

Just like germs wouldn't affect us, we wouldn't be able to digest anything that's native to the planet. We would have to destroy and replace the local ecosystem and replace it with Terran flora and fauna.
That means the colonists would need to bring enough food to last them until the first harvest, which is another can of worms. Are the seasons on the planet similar enough to not screw too much with our food crops ?

Here's where genetic engineering comes into play. The biosphere (including seasons) would need to be studied for a time, and Terran foodstuffs engineered to be compatible enough to grow on alien soil. Otherwise whatever human-miscible you plant just won't stick.

Then there's the ethical question: Do we have the right to just bulldoze an entire biosphere and exterminate species that could someday develop intelligence ?

When has humanity ever asked itself such a question?

And if our survival were at stake, it wouldn't even be in the mind of bio-ethicists.

 

[Kyriakos]

I am not optimistic regarding human space colonization. It may be attempted, but probably won't lead to long-term establishment. Having a few mining facilities on comets/other is more likely. After all, why expect humans to fare better in a different planet, when we even managed to ruin this one?

 

[Imaus]

Do you see the course humanity is going down?

If we find a world with life on it, we'll probably be too worried about cross contamination, interference with the local biosphere and worried about other compatibility issues to colonize it.

If people want a planet, they'll just terraform or para-terraform a barren or barren wet rock, and there seems to be a lot of those. I think most people would live in habitats. Each has a benefit: Planets are hard to crack, have a lot of room, and feel 'natural'. Habs are easy to construct, easy to expand, easy to replace; even if they're easier to destroy (though planets are easy to *hit*, contravise). And both of those allow humans and the Gaian biosphere to flourish without the ethical, environmental, and biological concerns of dealing with indig biospheres.

Anyway OP is discussing a 'barren wet rock'. The problem then is coating it with enough algae mats on both sea and water to basically replace soil for the first few...centuries? Decades at best. Then every meter or so of livable space has to be tilled and manually nutritioned and gardened to produce our flora enviorns. Not hard; basically what needs to be done on Mars or Venus anyway.

A lot of algae...a lot.

 

[El_Machinae]

Do we have the right to just bulldoze an entire biosphere and exterminate species that could someday develop intelligence ?

I don't think we have any obligation to a future intelligence, except insofar as we affect its actual existence.

Once you know that an intelligence will exist, I think you have a moral obligation. So, we have an obligation to future human inheritors of the Earth, for example. But I don't think we're obliged to create a future intelligence, except insofar as how it would affect other future intelligences.

By analogy, I have no obligation to purchase a puppy. But if I plan on having a baby, I certainly should think about whether bringing a puppy into their life would improve it. If it significantly would, I might have an obligation to buy a puppy.

 

[Kyriakos]

I am not really seeing such sensitivity on our side anyway. I mean we do breed various gaian animals with the sole purpose of eating them. And many others just so we can literally fleece them
Alien lifeforms have no rights.

 

[NukeAJS]

Lord of Shadow got the second problem IDed -- food production. Also, El_Machinae's suggestion of Issac Arthur is right on point. Issac Arthur probably made close to 20 videos about this subject from various different angles/problems. Many of his ideas are below.

The idea that you would build this massive starship to escape Earth for whatever reason is illogical when you think about it. It will take thousands of years, tens of thousands of years, to get there. If you can make a ship where millions of people are alive and actually living their lives (instead of stasis or some other kind of "sleeper" tech) ... didn't you achieve your goal of getting off Earth and surviving elsewhere? You've basically already succeeded. Just find a planetary ring system that had a good mix of elements/chemicals/minerals etc. and sit there and orbit for generations until a new pioneering spirit comes around and they leave in their own ship or take control of the mother-ship. This is because:

We're talking hundreds or even thousands of generations in the future, even with very good medicine/life extension tech. Ignoring culture and society for a moment, as Issac Arthur said: "gravity wells are for suckers." Many things become a lot harder in a gravity environment as opposed to simulated (spinning tube) gravity. Building and launching spaceships, for example. If such a generation ship existed (with a whole society working and living their lives), it would have to make pit stops. There's no way to have 100% energy efficiency and we can't just make matter like we make electricity. That means everything you want to make/maintain (people, food, consumer products, the ship's systems) has to take its energy from something else. Ideally, we'd have a large stock of raw materials on-board. It would probably be over 90% of the ship's mass when we set-out. But it's impossible to account for everything that can go wrong, especially when we're talking about thousands of years.

There's a lot more points to be made here but I'll start cutting to the chase -- you'd probably end up colonizing the systems between Earth and your target planet and you might get to that target planet much, much later than expceted. When a detour happens, it will take a long time to restock -- a very long time. After a generation or more, some people are probably going to stay behind for various different reasons -- religious beliefs, political disagreements, or just simply being bold and adventurous because being constantly in motion is the status quo and the cultural norm. Staying behind and living in a miniature (compared to the mother-ship) spinning tube is now the bold thing to do. Not only is it bold, it's WAY safer. When things go wrong, from a material perspective -- just build and/or launch ships to go get the materials you need. When you're in interstellar space, the stakes are MUCH higher because detouring to restock might simply be implausible due to the distances/times involved. Scarcity becomes a terrifying problem with just one obvious solution ...

In AI programming, this is called ethics drift and it's very much in play here with humans. Even assuming no or very little scientific/technological advancement (which is a catalyst for cultural advancement/change and extremely detrimental to future generations), the generation to generation change would make it near impossible that the ship's original goal would remain the same -- to colonize another planet. Imagine being the 4th or 5th generation of such a ship where the 1st generation -- the ones that lived on Earth and left -- told you about Earth and "the mission". Earth might sound interesting, but you've only known a spinning tube and all the stars are just as big as all the rest. Now that first generation says no more than 2 kids, rationing is very strict, "the mission" is shoved down your throat, you've only seen pictures of planets and stars, communicating with Earthlings is becoming less and less practical due to light-lag, and this comes from a bunch of old geezers from a planet called Earth whose stupid dream you're having to carry on your back because you want to do your own thing. Ok, now imagine you're the 300th generation

So, the most likely situation is that you don't have a minority faction that stays behind all the time, you would probably get the majority faction to stay behind. That means the mother-ship stays behind in its new system, hovering around a gas giant and harvesting asteroid/moons for raw materials. In a generation or more, you'd get factions that want to leave and probably make their own ship and fly away or take-over the mother-ship and start "the new mission" and this seems absolutely revolutionary to you. You'd become generation 1 all-over again with a completely different ethos, faith, and history.

 

[Narz]

What challenges would remain? Let's say the planet is littered with gigantic animals that would more or less be their equivalent of dinosaurs. Would modern technology be enough to make us consistently at the top of the food chain?

Lol the prehistoric world was littered with giant animals & ancient humans took them out pretty efficiently, I'm pretty user our descendants tens of thousands of years from now will do just fine.

There are no habitable planets anywhere near within reach of us, even getting humans to Mars is a pipe dream right now (and Mars is not habitable).

 

[Leifmk]

Lol the prehistoric world was littered with giant animals & ancient humans took them out pretty efficiently, I'm pretty user our descendants tens of thousands of years from now will do just fine.

Yeah, our ancestors used the horribly unfair trick of cooperating in a group, with plans, contingencies, ambushes, and sharpened sticks. That's about all it would take to kill a land animal of any size.

(Large sea animals were safer, until we developed good enough boats.)

 

[EgonSpengler]

If you can make a ship where millions of people are alive and actually living their lives (instead of stasis or some other kind of "sleeper" tech) ... didn't you achieve your goal of getting off Earth and surviving elsewhere? You've basically already succeeded. Just find a planetary ring system that had a good mix of elements/chemicals/minerals etc. and sit there and orbit for generations until a new pioneering spirit comes around and they leave in their own ship or take control of the mother-ship.

I think The Expanse, both the book series and the tv show, does a good job of outlining how enormous off-Earth populations might live in a variety of places around the Solar System, including aboard ships. To my memory, the only hand-wavey thing they do in their tech is a constant-thrust ship drive that doesn't require massive amounts of fuel. I think, after that one magic trick, they attempted to create a plausible off-Earth society.

Lol the prehistoric world was littered with giant animals & ancient humans took them out pretty efficiently, I'm pretty user our descendants tens of thousands of years from now will do just fine.

Just this morning I read an article about how humans wiped out woolly mammoths in Siberia at the end of the Pleistocene Era, 10-20,000 years ago.

 

[hobbsyoyo]

I don't think food production will be a major concern on an alien planet. You can sterilize the soil pretty trivially of alien germs and manufacturing supplemental soil nutrients from raw inputs is also trivial for interstellar travelers.

The greatest challenge for space colonization is finding enough motivation to shoulder the monumental expense it'd require to develop the means for it. Even if we had a sufficiently Earth-like target within reach.

Leaving our solar system will be a massive undertaking but I think colonizing other planets in our own solar system is become less and less of a hurdle. Obviously we're not there yet but launch costs are falling precipitously as our technology improves. The shuttle cost ~$20k/kg to put things in space and there are rockets now that achieve around 1/10 to 1/20th of that with others in development that could conceivably bring the price down to the low $100's per kilo.


One fact I just found out about Mars is that there is not enough gas trapped inside it to ever give it a decent atmosphere. This physicist who runs an online show for PBS did a deep-dive analysis and found that even if you melted the crust and a lot of the mantle to wring out every gas molecule, you still would not end up with a decent atmosphere - Mars has just lost too much volatile gases (nitrogen, oxygen, etc) to space to ever replace it with 'hidden' stores like gases trapped in rocks. You will have to bring the gas from external sources, unfortunately. There is enough water to build a decent ocean but it will be mostly shallow and probably not deep enough to really moderate the climate. Luckily, if you're throwing comets at Mars to deposit gas, you'll naturally bring a lot of water with them.

 

[Imaus]

I don't think food production will be a major concern on an alien planet. You can sterilize the soil pretty trivially of alien germs and manufacturing supplemental soil nutrients from raw inputs is also trivial for interstellar travelers.

Leaving our solar system will be a massive undertaking but I think colonizing other planets in our own solar system is become less and less of a hurdle. Obviously we're not there yet but launch costs are falling precipitously as our technology improves. The shuttle cost ~$20k/kg to put things in space and there are rockets now that achieve around 1/10 to 1/20th of that with others in development that could conceivably bring the price down to the low $100's per kilo.


One fact I just found out about Mars is that there is not enough gas trapped inside it to ever give it a decent atmosphere. This physicist who runs an online show for PBS did a deep-dive analysis and found that even if you melted the crust and a lot of the mantle to wring out every gas molecule, you still would not end up with a decent atmosphere - Mars has just lost too much volatile gases (nitrogen, oxygen, etc) to space to ever replace it with 'hidden' stores like gases trapped in rocks. You will have to bring the gas from external sources, unfortunately. There is enough water to build a decent ocean but it will be mostly shallow and probably not deep enough to really moderate the climate. Luckily, if you're throwing comets at Mars to deposit gas, you'll naturally bring a lot of water with them.

I don't see this as unfortunate, I see that as the only way to do it?

I don't know where or why this idea that somehow, a dead mars with two small ice caps is enough to bootstrap it again. Maybe it was sold to the public somewhere (and Total Recall didn't help) but the implication to me, is, that we'll need extensive snow-line ops to get in comets and gasses in.