Should we spread life in the universe?

[m4v]

kind of a moot question, since we don't have the ability to do so yet, and no guarantees that we will either.

[kerbiloid]

Mother Nature will take care about that.

The very first terrestrial life being spread in the Universe will be lifeforms from a fastfood closest to the launchpad - where space center workers had their lunch before putting a fairing onto a martian rocket.

[HazelPine]

8 hours ago, kurja said:

If a world is "sterile of life" it by definition would not have ecosystems on it, no?

Eventually we should spread out to the universe and certainly it would not be right to just stomp on any life already there should we ever find it, but I don't think we should be too concerned of simple life, like bacteria or such. We're not worried about those here on earth either as long as it does not concern our own well being.

As for altering lifeless alien worlds themselves, as human presence would - the universe isn't going to mind. Neither should we.

 

 

8 hours ago, SinBad said:

The problem is prooving sterility. A vocal portion of our population will only be satisfied if we micoscopically inspect every grain of sand on a potential planet all the way down to the core. That opinion could also be argueably extended to asteriods and comets. Fortunatly, its very hard to make a cute and clever logo with a negative space bacteria. so like today, the folks who make the descisions can feel free to ignore them.

My personal opinion though, if it tastes good, eat it. If it eats dirt and poops gold in a vacuume, farm it. Exploitation begins in the home... star system. Humanity exploits natural resources, including those that metabolise. I think planets with complex ecosystems would be prime candidates. Imagine if we found a less advanced intelligent race. No human rights violations there, capitalists can have all the slave labor they want without having to trick them into thinking they have freedom first by giving them minimum wage.

What I meant was that I thin we shouldn't spread life around the universe until we know (at least) a lot about the planet/star system/galaxy in the way it is. Imagine an example with mars: If we had the ability to colonize it right now, we still shouldn't since any fragile geological formations and undisturbed things beneath the surface could be affected without us realizing because we wouldn't have discovered it yet. So we'd send a couple scientific expeditions and maybe I guess leave large swaths of the planet as 'natural reserves', just to be sure.

 

After we learn all there is to know about it the way it is right now, as we're doing with robots and probes, I'd say it's fair game.

Edited June 5, 2016 by Pine

[SinBad]

4 hours ago, Bill Phil said:

Not how space works. 

We wouldn't expand as a sphere. It'll be a strange blob of a few stars at a time. 

Let's say we expand across the entire solar system out past Neptune. There are plenty of resources in that volume. Asteroids, comets, Trojans, moons, and Kuiper Belt Objects.

Blobbyness granted, to an extent. After you hit a certain size, surface variations of a few lightyears wont be noticeable. Thats assuming we ever actualy go interstellar. It holds true in the solar system as well. Simplify it into 2 dimensions into the mean orbital plane, the area of occupation increases faster than the circumfrence, where new resources are found. We wont see limiting effects right away as there is just so much more up there than down here.

But if you set aside the planets as nature reserves, and maybe comets and c type asteroids just in case, that significantly reduces the available resources. At some point those will be consumed. Thats when we start looking at the reserves. The rich will petition for them to be exploited so they can get richer, the poor will too as population pressure causes crowding and shortages of the basic necessities, like food, water and air. Antarctica used to be an exploitation free zone, now we are considering oil and mining down there.

Where ever we go, there will be biological contamination. We have managed to breed superbugs in a few decades just by overusing antibiotics. On centuries long timescales we have inadvertantly created extremophiles capable of surviving just about anywhere we go. Its not a question of should we spread life, but when will we accept that the only way not to is to stay home.

[Bill Phil]

13 minutes ago, SinBad said:

Blobbyness granted, to an extent. After you hit a certain size, surface variations of a few lightyears wont be noticeable. Thats assuming we ever actualy go interstellar. It holds true in the solar system as well. Simplify it into 2 dimensions into the mean orbital plane, the area of occupation increases faster than the circumfrence, where new resources are found. We wont see limiting effects right away as there is just so much more up there than down here.

But if you set aside the planets as nature reserves, and maybe comets and c type asteroids just in case, that significantly reduces the available resources. At some point those will be consumed. Thats when we start looking at the reserves. The rich will petition for them to be exploited so they can get richer, the poor will too as population pressure causes crowding and shortages of the basic necessities, like food, water and air. Antarctica used to be an exploitation free zone, now we are considering oil and mining down there.

Where ever we go, there will be biological contamination. We have managed to breed superbugs in a few decades just by overusing antibiotics. On centuries long timescales we have inadvertantly created extremophiles capable of surviving just about anywhere we go. Its not a question of should we spread life, but when will we accept that the only way not to is to stay home.

New resources will be found within the volume. 

We won't expand as a singular sphere either. More like multiple weird shapes.

In space borders make no sense. Things move. People will already be beyond the frontier of settlement. Just as there were already people in the frontier of the old west.

[SinBad]

41 minutes ago, Bill Phil said:

New resources will be found within the volume. 

We won't expand as a singular sphere either. More like multiple weird shapes.

In space borders make no sense. Things move. People will already be beyond the frontier of settlement. Just as there were already people in the frontier of the old west.

Here is a glass of water. Drink all the water. Look into the glass and find me more water in there. New resources dont appear within a given volume. On a stellar scale, sure, a new comet might wander through, but those volatiles wont support our growth (by the time we need to be looking for wandering visitors) for very long, minutes. Maybe.

And yes, it will be multiple weird shapes, but the effect holds. For example, we have colonised all the systems within 20 lightyears. Its not a sphere, because stars are not uniformly distributed.  but lets look at the numbers and leave geometry out of it for the moment. Each of those colonised systems has to consume resources fast enough to support its own population growth, the oldest colonies have run out of free mass to turn into new habitats, so the younger colonies must over produce in order to supply the growth of the old (by accepting further immegration) as well as their own. In the first years of expansion sol will be the only old system, and it will be depleted. 4 new colonies must now supply their own growth as well as 1/4 sols growth, or 125% the rate of the original system. Thats probably manageable. But the new colonies will become depleted faster than sol. Assuming they are forward thinking enough to keep enough resources in reserve for another 4 colonies each, that then makes 20 new colonies and 5 old ones. Again gives 100 new colonies and 25 old ones. Now we are getting close to the number of stars within 20 light years. At some point, we wont have enough ships to keep the excess population moving outwards. Our population grows at the moment by 1.1% each year. If it takes 100 years to convert everything in our solar system (except planets, and maybe c type asteroids and comets, and assuming some pretty awesome powers of mining and construction) that puts our population at roughly 101, 976 billion in habitats around the system. The 101st year we need to export 1.1% of that population, or 10, 197 billion people, and every year after that as well, otherwise sol starves because we dont have the resources left to build habitats for the extra 1.1% per year. Thats the population pressure we are dealing with. Now assuming we can travel at light speed and dont suffer acceleration or deceleration times, thats a little over 4 years transit time to the next system over. The first years colonists will increase their population to 14, 930 billion while in transit, with another 3 waves of colonists just as big hot on their heels the day they arrive. Once there, the ships unload and return to sol for more, so 8 colony fleets always in motion. That works till the colony is also depleted, now we need more ships to get sols excess population, as well as the first colonies excess to the second. Thats alot of mass just in the hulls, and it has to come from somewhere as well. Very quickly we hit the point where new territory can no longer absorb one year of immegration before being depleted. Thats when we start ripping planets apart to build walls, food, water and air. Lets say that one of these 100, 000 billion population colony fleets arrives in a system with a race about where we are now. They need to consume the available mass in one year just to expand their fleet enough to hold the babies that will be born on the way to the next system. The rights of the natives wont be considered. 7 billion aliens rights to asteriods they are not even using yet vrs the lives of 100, 000 billion humans? We will leave them their home planet, but everything else is ours. That race will not have the chance to expand as we did. And there wouldnt be anything they could do to stop us. The real problem comes in when the fleet arrives at a system and cant meet the resource requirements. The expansion stalls then. The human empire dies from inside out . never having gotten 110 light years from home. To be fair, the old systems dying would buy us some time, maybe we would have a frontier of new systems with a layer of older ones that can still reach new colonies, but the core of the civilisation will be empty of everything.

Tldr: we can be as moral as we like right now, but when it comes time to get down to expansion, sentiment will kill us.

[PB666]

1 minute ago, SinBad said:

Here is a glass of water. Drink all the water. Look into the glass and find me more water in there. New resources dont appear within a given volume. On a stellar scale, sure, a new comet might wander through, but those volatiles wont support our growth (by the time we need to be looking for wandering visitors) for very long, minutes. Maybe.

And yes, it will be multiple weird shapes, but the effect holds. For example, we have colonised all the systems within 20 lightyears. Its not a sphere, because stars are not uniformly distributed.  but lets look at the numbers and leave geometry out of it for the moment. Each of those colonised systems has to consume resources fast enough to support its own population growth, the oldest colonies have run out of free mass to turn into new habitats, so the younger colonies must over produce in order to supply the growth of the old (by accepting further immegration) as well as their own. In the first years of expansion sol will be the only old system, and it will be depleted. 4 new colonies must now supply their own growth as well as 1/4 sols growth, or 125% the rate of the original system. Thats probably manageable. But the new colonies will become depleted faster than sol. Assuming they are forward thinking enough to keep enough resources in reserve for another 4 colonies each, that then makes 20 new colonies and 5 old ones. Again gives 100 new colonies and 25 old ones. Now we are getting close to the number of stars within 20 light years. At some point, we wont have enough ships to keep the excess population moving outwards. Our population grows at the moment by 1.1% each year. If it takes 100 years to convert everything in our solar system (except planets, and maybe c type asteroids and comets, and assuming some pretty awesome powers of mining and construction) that puts our population at roughly 101, 976 billion in habitats around the system. The 101st year we need to export 1.1% of that population, or 10, 197 billion people, and every year after that as well, otherwise sol starves because we dont have the resources left to build habitats for the extra 1.1% per year. Thats the population pressure we are dealing with. Now assuming we can travel at light speed and dont suffer acceleration or deceleration times, thats a little over 4 years transit time to the next system over. The first years colonists will increase their population to 14, 930 billion while in transit, with another 3 waves of colonists just as big hot on their heels the day they arrive. Once there, the ships unload and return to sol for more, so 8 colony fleets always in motion. That works till the colony is also depleted, now we need more ships to get sols excess population, as well as the first colonies excess to the second. Thats alot of mass just in the hulls, and it has to come from somewhere as well. Very quickly we hit the point where new territory can no longer absorb one year of immegration before being depleted. Thats when we start ripping planets apart to build walls, food, water and air. Lets say that one of these 100, 000 billion population colony fleets arrives in a system with a race about where we are now. They need to consume the available mass in one year just to expand their fleet enough to hold the babies that will be born on the way to the next system. The rights of the natives wont be considered. 7 billion aliens rights to asteriods they are not even using yet vrs the lives of 100, 000 billion humans? We will leave them their home planet, but everything else is ours. That race will not have the chance to expand as we did. And there wouldnt be anything they could do to stop us. The real problem comes in when the fleet arrives at a system and cant meet the resource requirements. The expansion stalls then. The human empire dies from inside out . never having gotten 110 light years from home. To be fair, the old systems dying would buy us some time, maybe we would have a frontier of new systems with a layer of older ones that can still reach new colonies, but the core of the civilisation will be empty of everything.

Tldr: we can be as moral as we like right now, but when it comes time to get down to expansion, sentiment will kill us.

Within each stars hill sphere there is a tremendous mass of resources at relatively small gravity well depth, the issue in space is energy, you have to burn alot of that mass tonsustain existence unless you have a very stable star with a planet in the right zone, Planet 9 is likely composed of impacts from kuiper belt and oort collision, cosequently in a spreading modality we have no hope of maximizing the resource depletion, particluraky since we have modalities for locating things at great distances and unintelligent inertial bodies only have their cross sectional profile along the relative paths of travel. 

[SinBad]

7 minutes ago, PB666 said:

Within each stars hill sphere there is a tremendous mass of resources at relatively small gravity well depth, the issue in space is energy, you have to burn alot of that mass tonsustain existence unless you have a very stable star with a planet in the right zone, Planet 9 is likely composed of impacts from kuiper belt and oort collision, cosequently in a spreading modality we have no hope of maximizing the resource depletion, particluraky since we have modalities for locating things at great distances and unintelligent inertial bodies only have their cross sectional profile along the relative paths of travel. 

Even tremendous amounts of resources crumble when faced with contiinuous growth. I diliberatly avoided mentioning the energy requirements and instead lumped it in with 'habitats' using that term to represent all of things we need to live in one simplified word.

[Bill Phil]

20 minutes ago, SinBad said:

Here is a glass of water. Drink all the water. Look into the glass and find me more water in there. New resources dont appear within a given volume. On a stellar scale, sure, a new comet might wander through, but those volatiles wont support our growth (by the time we need to be looking for wandering visitors) for very long, minutes. Maybe.

And yes, it will be multiple weird shapes, but the effect holds. For example, we have colonised all the systems within 20 lightyears. Its not a sphere, because stars are not uniformly distributed.  but lets look at the numbers and leave geometry out of it for the moment. Each of those colonised systems has to consume resources fast enough to support its own population growth, the oldest colonies have run out of free mass to turn into new habitats, so the younger colonies must over produce in order to supply the growth of the old (by accepting further immegration) as well as their own. In the first years of expansion sol will be the only old system, and it will be depleted. 4 new colonies must now supply their own growth as well as 1/4 sols growth, or 125% the rate of the original system. Thats probably manageable. But the new colonies will become depleted faster than sol. Assuming they are forward thinking enough to keep enough resources in reserve for another 4 colonies each, that then makes 20 new colonies and 5 old ones. Again gives 100 new colonies and 25 old ones. Now we are getting close to the number of stars within 20 light years. At some point, we wont have enough ships to keep the excess population moving outwards. Our population grows at the moment by 1.1% each year. If it takes 100 years to convert everything in our solar system (except planets, and maybe c type asteroids and comets, and assuming some pretty awesome powers of mining and construction) that puts our population at roughly 101, 976 billion in habitats around the system. The 101st year we need to export 1.1% of that population, or 10, 197 billion people, and every year after that as well, otherwise sol starves because we dont have the resources left to build habitats for the extra 1.1% per year. Thats the population pressure we are dealing with. Now assuming we can travel at light speed and dont suffer acceleration or deceleration times, thats a little over 4 years transit time to the next system over. The first years colonists will increase their population to 14, 930 billion while in transit, with another 3 waves of colonists just as big hot on their heels the day they arrive. Once there, the ships unload and return to sol for more, so 8 colony fleets always in motion. That works till the colony is also depleted, now we need more ships to get sols excess population, as well as the first colonies excess to the second. Thats alot of mass just in the hulls, and it has to come from somewhere as well. Very quickly we hit the point where new territory can no longer absorb one year of immegration before being depleted. Thats when we start ripping planets apart to build walls, food, water and air. Lets say that one of these 100, 000 billion population colony fleets arrives in a system with a race about where we are now. They need to consume the available mass in one year just to expand their fleet enough to hold the babies that will be born on the way to the next system. The rights of the natives wont be considered. 7 billion aliens rights to asteriods they are not even using yet vrs the lives of 100, 000 billion humans? We will leave them their home planet, but everything else is ours. That race will not have the chance to expand as we did. And there wouldnt be anything they could do to stop us. The real problem comes in when the fleet arrives at a system and cant meet the resource requirements. The expansion stalls then. The human empire dies from inside out . never having gotten 110 light years from home. To be fair, the old systems dying would buy us some time, maybe we would have a frontier of new systems with a layer of older ones that can still reach new colonies, but the core of the civilisation will be empty of everything.

Tldr: we can be as moral as we like right now, but when it comes time to get down to expansion, sentiment will kill us.

You misunderstand my point. The resources on a per solar system basis can support trillions of humans. We're not going to run out anytime soon.

Not only that, but the stars themselves are an energy source.

10 minutes ago, SinBad said:

Even tremendous amounts of resources crumble when faced with contiinuous growth. I diliberatly avoided mentioning the energy requirements and instead lumped it in with 'habitats' using that term to represent all of things we need to live in one simplified word.

But with more resources you can gather more resources

[SinBad]

15 minutes ago, Bill Phil said:

You misunderstand my point. The resources on a per solar system basis can support trillions of humans. We're not going to run out anytime soon.

Not only that, but the stars themselves are an energy source.

But with more resources you can gather more resources

Trillions, agreed. 100 trillion in the next 100 years? I dont think we can move that fast. Stars are en energy source, but is it enough to support growth on this scale? We By the time we hit 100 trillion we will be staring to look like a dyson cloud (i would say sphere but that confuses people into thinking he meant a single solid structure, instead of a collection of habitats in various orbits) the amount of energy we would need to build habitats for 100 trillion in 100 years is phenomenal. I dont think we could expand our infrastructure fast enough to keep pace.

And yes, more resources means you can gather more resources, but again, energy and time. In a hundred years we need to be adding 323,000 living spaces and the food, air, water and power to support them every second.

[TheAurora]

8 minutes ago, SinBad said:

Trillions, agreed. 100 trillion in the next 100 years? I dont think we can move that fast. Stars are en energy source, but is it enough to support growth on this scale? We By the time we hit 100 trillion we will be staring to look like a dyson cloud (i would say sphere but that confuses people into thinking he meant a single solid structure, instead of a collection of habitats in various orbits) the amount of energy we would need to build habitats for 100 trillion in 100 years is phenomenal. I dont think we could expand our infrastructure fast enough to keep pace.

And yes, more resources means you can gather more resources, but again, energy and time. In a hundred years we need to be adding 323,000 living spaces and the food, air, water and power to support them every second.

Your argument seems to be much like the idea of Thomas Malthus. He proposed that human population growth would outpace our ability to sustain ourselves. That was a long time ago, and his proposed catastrophe never happened. Our technological ability to gather resources and support ourselves developed tremendously. I bet he couldn't conceive of a system to support over 7 billion people (and yes, our system is not perfect. I acknowledge the fact that much of the population is short on resources, but they still survive somewhat. Our population is not rapidly declining like he proposed) but here we are today. It is hard for us to conceive of trillions of people, but it is possible. I agree with Bill Phil, more resources enables us to gather more resources. We will be able to sustain ourselves. A hundred trillion people is most likely possible.

[SinBad]

I dont disagree that sustaining 100 trillion is possible. I just dont think we will get there in time considering a 1.1% growth rate puts us there by 2116. Earth alone  Couldnt support that much even if we stop farming in the dirt and all start eating yeast paste. For every one person you see now, thats 10,000 people in 100 years time. Even if we get better at everything, will we have time to build it? A big building can take a decade to construct, and thats only after a decade of planning, so from someone saying 'we need a higher housing density' to actually moving people in, is about 20 years. The nearest estimates for asteroid mining are 20 years away. Fusion 25 years. Orbital cities are way out at 50. When malthus was estimating, the earth had a few centuries to expand and the rate of technilogical advancement was very slow. Now technology is advancing quickly and we are reducing the carrying capacity of the planet at the same time we are expanding our population and rates of consumption. Malthus had the right idea, he just didnt have all the facts yet. Our biggest problem at the moment is how rapidly new technologies can be adopted. We could have an amasing breakthough this afternoon, but how many years until that starts making changes in every day life? We dont have time for decades long construction projects. If we do manage to dump ourexcess population into space we have to start looking at the carrying capacity of our solar system.

Ffurther rreading :Homogeneous cosmology with aggressively expanding civilizations S. Jay Olson (Submitted on 17 Nov 2014 (v1), last revised 20 Oct 2015 (this version, v2))

[Raven Industries]

I think we tend to underestimate just how stubborn humans are when they want to survive.

[kerbiloid]

10 hours ago, SinBad said:

Here is a glass of water. Drink all the water. Look into the glass and find me more water in there. New resources dont appear within a given volume.

A day later this amount of water respawns agian and again. Just to be filtered.

Infinite "continuous growth" makes no sense. Colonize new planets to get more resources to colonize more planets?
Once you reach an Earth capacity (several billions) you anyway stop. Only millenia later you can colonize other planets - but those people shall not, as a constant population will be already usual for them for many generations.

The resources recycling eliminates the rest of sense of infinite extraterrestrial expansion. When you recycle 99% of you resources, you can drop your mining indusrty down to 1% of its original values.

Edited June 6, 2016 by kerbiloid

[SinBad]

20 minutes ago, kerbiloid said:

-snip-
Once you reach an Earth capacity (several billions) you anyway stop. Only millenia later you can colonize other planets -snip-

Hehe, good luck convincing the entire planet to allow their reproduction to be regulated. And if you can, why wait until you are at carrying capacity? Ive never said that sustaining a set population without new resources was impossible. Sure, recycle away till the sun goes out. The stay at home population is never going to recieve more resources, the amounts required to be shipped lightyears back to sol would be prohibitive, so heavy mass reuse is a requirement. personally i dont believe you will ever be able to regulate population growth, and that will require new resources to support. And if you cant import resources, export the need for resources: send your excess population to where the resources are.

 

All im saying is, i believe that by the time we are in a position to need to make conservation descisions, the only conservation we will be thinking of is human life.

[kerbiloid]

3 minutes ago, SinBad said:

Hehe, good luck convincing the entire planet to allow their reproduction to be regulated.

As if somebody has a choice. By will or not, Mother Nature is delicate like a rusty guillotine.

5 minutes ago, SinBad said:

And if you can, why wait until you are at carrying capacity?

"Wait"? The biggest rivers are already 90% dismantled for irrigation.

[1of6Billion]

My calculator thinks 7 billion population growing 1,1% every year for 100 years is a little under 21Billion. Not 100 Trillion.

[TheAurora]

1 hour ago, 1of6Billion said:

My calculator thinks 7 billion population growing 1,1% every year for 100 years is a little under 21Billion. Not 100 Trillion.

Yes. I was thinking the same thing. I do not know where this "100 Trillion" number for Earth came from. Our current growth seems to be declining, or it is at least predicted to start capping out.

 

1 hour ago, SinBad said:

Hehe, good luck convincing the entire planet to allow their reproduction to be regulated. 

You don't necessarily need to do that. From current experience of population growth on Earth, as a nation develops its growth rates decline. The people themselves naturally seem to do other things instead of reproducing. Take Europe or Japan as an example. Since we are still talking about humans spreading through the universe, I believe this will still apply. As a planet or colony reaches it's fully developed stage, we will see the population cap, just like Earth now and all of its major nations.

[kerbiloid]

21 minutes ago, TheAurora said:

The people themselves naturally seem to do other things instead of reproducing.

Especially if they live 1000 years (far future then) and can hardly distinguish their great-great-great-great-grandchildren from their great-great-great-great-great-great-grandchildren, and every, say, fourth street bypasser is their kinsman.

[PB666]

Population should have capped earlier, current problem is the dearth of education in the developing world, particularly education of girls. 

You cannot realistically expect to have great, .................., great grandchildren on the same street unless its a necropolis. At some point for this to happene you would have to delay childbirth to prevent overpopulation. As it stands in the developed world longevity is starting to fall, people are working longer and living shorter times in retirement. A greater burden of childrearing has shifted to the older generation from a rather careless younger generation. Not exactly a productive circumstance. 

[SinBad]

4 hours ago, 1of6Billion said:

My calculator thinks 7 billion population growing 1,1% every year for 100 years is a little under 21Billion. Not 100 Trillion.

You are right. I misplace the decimal on 1.1% when multiplying it out. Thats embarrasing.

[cubinator]

Was it ethical for the lobe-finned fish to come and disturb the perfection of the dry world? Should they have stayed in the water and let whatever primordial bacteria there might be keep going on with their dry lives? They didn't care. They came to land because it would help them survive longer, ultimately by hundreds of millions of years.

Moving into the stars would help our species survive longer, ultimately by hundreds of billions of years.

Life spreads. It's a fundamental part of being alive, because being able to reproduce is an incredible evolutionary advantage. It's what drives evolution. Why should we decide to stop spreading? The undisturbed nebula was wrought into a protoplanetary disc. The undisturbed planets gave birth to life. The undisturbed continents were colonized by life. The undisturbed life was hurt by asteroids, comets, and volcanoes. The undisturbed land was farmed by humans. The undisturbed isolated civilizations were assimilated by explorers. The undisturbed forests were cut down. The undisturbed rocks were mined for resources. The undisturbed rivers flooded for dams. It is inevitable that the undisturbed planets will be occupied by our settlements and our robots. The undisturbed subsurface oceans of the ice worlds will be drilled through and probed. The undisturbed asteroids will be processed for minerals and fuel. The undisturbed stars will be visited, be it by postage stamps with lasers or by giant colony ships through wormholes. The undisturbed dust will be kicked up by human boots. The undisturbed craters will be constructed into spaceports. The undisturbed air may be pumped full of oxygen, and the undisturbed space occupied with stations. It doesn't really matter. Everything will be ok, and the future will be really cool! Anyways, I've rambled too long. I'll just go ahead and answer the poll now.

[vger]

Is this question limited to just colonization or terraforming? Seems like it might be, based on responses, but that seems nearsighted. Even with sterilization procedures, it seems like it would be very likely that some probes we've sent to other worlds, arrived there with some microbial hitchhikers who may have survived. So, we've already begun to spread life. Whether or not any extremophiles survived long-term, that's another matter.

Edited June 7, 2016 by vger

[PB666]

43 minutes ago, vger said:

Is this question limited to just colonization or terraforming? Seems like it might be, based on responses, but that seems nearsighted. Even with sterilization procedures, it seems like it would be very unlikely that every probe we've ever sent to another world, arrived there with some microbial hitchhikers who may have survived. So, we've already begun to spread life. Whether or not any extremophiles survived, that's another matter.

3.3 minutes in a space bound ceasium sterilizer, no problem. 

Simply restrict colonized planets to those recently formed form protoplanetary disk. 

i think if you deposited select microbes on a workd at early enogh stage the charcarpteristics of the world and not the microbes themselves would govern its evolution. If you threw complex ediacaran biota or anything more advanced down, those would largely determine the course of evolution. 

I think we are trying to fabricate a conflict that does not exist, humans and earth life are more thermodynamically favorable than really primative forms and the universe will age and go to diffusion of energy with or without our contribution, might as well contribute. 

[RainDreamer]

Well, lets just hope that we don't one day become the alien invaders in our movies: locusts like, moving between world to world destroy all lifeforms in between to consume and propergate.