One thing that's different from colonies on the Earth - space colonies would be extremely vulnerable to attack. So - any conventional war between colonies and Earth or of the colonies with each other would end quickly - with all the colonies destroyed.
You don't even need weapons.- just throwing rocks at each other at the kilometers per second spacecraft velocities would destroy a colony and be extremely hard to defend against. And with the colony surrounded by nothing but vacuum - only exception here - is upper atmosphere of Venus - and even then - there is nowhere outside of the habitat to escape to - so - there are no woods or mountains or any natural features to escape to, not in a spacesuit with just a few hours of air before you die, or die instantly if your spacesuit is damaged badly by a piece of flying debris from the explosion.
So - I think we won't be able to have permanent colonies in space, myself - unless we also at the same time achieve peace in space. Which we are perhaps on target towards given the Outer Space Treaty - we need some other way of resolving any conflicts in space that does not involve conventional warfare.
Similarly to the way that stags could easily kill each other in the rutting season - but instead - lock antlers in a ritualized combat that still sometimes does kill but normally leaves both parties - sometimes wounded - but basically still healthy.
Who knows what form it would take - games - third party arbiter - chance - just lots of talking through issues, ... But something would need to take place of war or space colonies will never last for any length of time.
There is also an economic thing. First space mining industries would be immensely wealthy - like the oil nations but more so - and that could lead to great hardship on the Earth. Similarly to the world wide hardship for many countries that followed on from the 1973 oil crisis, and still continues to this day with many countries still heavily in debt and having to cut back on public services just to pay interest on their debts which they incurred in 1973.
So - I think myself that at some point something will need to be done about that - and hopefully before rather than after. Some form of - benefit sharing - or sharing of technology at least "as a service" - so that anyone can use it - or some legal thing that makes sure that anyone on the Earth in some way or another has the ability to share in space mining and the benefits that flow from it.
If so - that would encourage a lot of mixing of population back and forth between space and the Earth - that anyone could fly into space eventually if they wanted to - and you would never get the situation where only those born in space colonies can afford to live there.
If that happens - then that could postpone the issue of independence of space colonies for some time.
Another thing is - that we have already reached peak child on the Earth - are no more children than there were a few years ago. Population is growing still because people are living longer.
Now - that might not be a permanent thing. Nigeria particularly has a rapidly growing population of people who have large families (so has rapidly growing population of children unlike almost anywhere else in the world) - so that might turn things around again.
However, Nigeria is currently is on track to have more people in Nigeria than China eventually - which seems a bit unlikely that it would continue as far as that.
So, they may well follow the same example as other developed countries - at some point - and have smaller families and their population stabilize like just about all the other countries.
If so - then we may reach a population peak later this century (as in some of the projections) - and then population of the Earth gradually fall to lower levels again. That could reduce pressure to go into space.
So then - given that space is nowhere near as easy a place to live as Earth - we may well never have more than small settlements in space. At least not billions of people living there. Thousands perhaps, millions even, but maybe never billions.
I think myself that that might be a good outcome. Because - we don't have any real risk of going extinct at present. Maybe a few hundred million years from now, yes. When the Earth loses its oceans as the sun heats up - then we - or rather the species that current Earth life has evolved into after several times the timespan since the dinosaurs - they may need to move to another planet.
But we don't need to do anything about that yet. And indeed - for instance ideas to terraform Mars - the ideas I've seen for that - only expect it to stay terraformed for perhaps hundreds of thousands of years, not for geological time periods. (With many things to go wrong so it doesn't work at all, and if it is possible to terraform it quickly - might also just unterraform as quickly).
There are several reasons why Mars can't keep an Earth like atmosphere and ocean over geological time periods - without mega-engineering or some major new idea about how the planet's biosphere works different from Earth.
So - by the time we or rather the species that follow us really do need to escape from Earth - any terraforming attempt on Mars done now - by half a billion years from now, when Mars might temporarily be really useful as a way to escape from red giant sun - would be just remains of ancient cities in a dust dry planet, chances are - and harder to terraform for them than if we had just left it alone.
And - there is another broader issue also.
I am not too bothered about humans colonizing our solar system - so long as we have enough restraint to not, for instance, colonize Mars before we have a chance to study what life might be there already, and are prepared to not colonize it at all if it is of more value to humanity in its pristine state.
So long as we are responsible in the way we colonize our solar system, I don't see too much of an issue with it - but then - if we colonize the galaxy - I see that as potentially a big issue.
Because - what would our descendants turn into - and what would they unleash - thousands of years into the future as they spread through the galaxy? And what would they do to the galaxy - with the power of self replicating machines, and able to make new biological entities and cyborgs etc etc?
It seems like a future that would turn the galaxy into many factions of beings that to us would be like the alien monsters of sci. fi - with obscure purposes and quite possibly come back and destroy the Earth..
Maybe there is some way to prevent us from doing this and colonize the galaxy sensibly and safely.
But - the more I think about it - and since nobody has come up with any convincing answers to this when I raise the issue - I suspect that any sensible ET will choose not to colonize the galaxy, only explore it.
I think - still just as a hypothesis of course - that only reckless short sighted ETs choose to colonize the galaxy. And that any ETS as reckless as that - I think probably destroy all their space colonies in their home planet solar system, long before they have a chance even to attempt their first interstellar mission.
Which might be why there are no ETs here already. Otherwise, surely by now, someone would have decided to colonize the galaxy and they would be here already. That's my favoured solution to the Fermi's paradox.
Which doesn't mean that the "sensible ETs" have to stay at home. They would explore the galaxy as much as they like - that's not a problem so long as they don't set up colonies wherever they go. But there probably aren't that many of them - nearest adventurous explorer could easily be hundreds, or even thousands of light years away and not yet received our radio transmissions - or messages from whatever probes they might have left in our solar system.
Or we might be the first ETs to evolve to technology in our galaxy - if so need to be especially careful how we proceed.
Or - might be that there is a safe and responsible way to colonize a galaxy without excessive risk to yourself and all the other ETs in the galaxy. But if so, I've no idea what it is - and not come across anyone else who has an answer that's at all convincing. Maybe some day we will find that answer though. It might require changes in ourselves and how we behave.
See also: Robert Walker's answer to What is your preferred answer to the Fermi paradox?
You don't even need weapons.- just throwing rocks at each other at the kilometers per second spacecraft velocities would destroy a colony and be extremely hard to defend against. And with the colony surrounded by nothing but vacuum - only exception here - is upper atmosphere of Venus - and even then - there is nowhere outside of the habitat to escape to - so - there are no woods or mountains or any natural features to escape to, not in a spacesuit with just a few hours of air before you die, or die instantly if your spacesuit is damaged badly by a piece of flying debris from the explosion.
So - I think we won't be able to have permanent colonies in space, myself - unless we also at the same time achieve peace in space. Which we are perhaps on target towards given the Outer Space Treaty - we need some other way of resolving any conflicts in space that does not involve conventional warfare.
Similarly to the way that stags could easily kill each other in the rutting season - but instead - lock antlers in a ritualized combat that still sometimes does kill but normally leaves both parties - sometimes wounded - but basically still healthy.
Who knows what form it would take - games - third party arbiter - chance - just lots of talking through issues, ... But something would need to take place of war or space colonies will never last for any length of time.
There is also an economic thing. First space mining industries would be immensely wealthy - like the oil nations but more so - and that could lead to great hardship on the Earth. Similarly to the world wide hardship for many countries that followed on from the 1973 oil crisis, and still continues to this day with many countries still heavily in debt and having to cut back on public services just to pay interest on their debts which they incurred in 1973.
So - I think myself that at some point something will need to be done about that - and hopefully before rather than after. Some form of - benefit sharing - or sharing of technology at least "as a service" - so that anyone can use it - or some legal thing that makes sure that anyone on the Earth in some way or another has the ability to share in space mining and the benefits that flow from it.
If so - that would encourage a lot of mixing of population back and forth between space and the Earth - that anyone could fly into space eventually if they wanted to - and you would never get the situation where only those born in space colonies can afford to live there.
If that happens - then that could postpone the issue of independence of space colonies for some time.
Another thing is - that we have already reached peak child on the Earth - are no more children than there were a few years ago. Population is growing still because people are living longer.
Now - that might not be a permanent thing. Nigeria particularly has a rapidly growing population of people who have large families (so has rapidly growing population of children unlike almost anywhere else in the world) - so that might turn things around again.
However, Nigeria is currently is on track to have more people in Nigeria than China eventually - which seems a bit unlikely that it would continue as far as that.
So, they may well follow the same example as other developed countries - at some point - and have smaller families and their population stabilize like just about all the other countries.
If so - then we may reach a population peak later this century (as in some of the projections) - and then population of the Earth gradually fall to lower levels again. That could reduce pressure to go into space.
So then - given that space is nowhere near as easy a place to live as Earth - we may well never have more than small settlements in space. At least not billions of people living there. Thousands perhaps, millions even, but maybe never billions.
I think myself that that might be a good outcome. Because - we don't have any real risk of going extinct at present. Maybe a few hundred million years from now, yes. When the Earth loses its oceans as the sun heats up - then we - or rather the species that current Earth life has evolved into after several times the timespan since the dinosaurs - they may need to move to another planet.
But we don't need to do anything about that yet. And indeed - for instance ideas to terraform Mars - the ideas I've seen for that - only expect it to stay terraformed for perhaps hundreds of thousands of years, not for geological time periods. (With many things to go wrong so it doesn't work at all, and if it is possible to terraform it quickly - might also just unterraform as quickly).
There are several reasons why Mars can't keep an Earth like atmosphere and ocean over geological time periods - without mega-engineering or some major new idea about how the planet's biosphere works different from Earth.
So - by the time we or rather the species that follow us really do need to escape from Earth - any terraforming attempt on Mars done now - by half a billion years from now, when Mars might temporarily be really useful as a way to escape from red giant sun - would be just remains of ancient cities in a dust dry planet, chances are - and harder to terraform for them than if we had just left it alone.
And - there is another broader issue also.
I am not too bothered about humans colonizing our solar system - so long as we have enough restraint to not, for instance, colonize Mars before we have a chance to study what life might be there already, and are prepared to not colonize it at all if it is of more value to humanity in its pristine state.
So long as we are responsible in the way we colonize our solar system, I don't see too much of an issue with it - but then - if we colonize the galaxy - I see that as potentially a big issue.
Because - what would our descendants turn into - and what would they unleash - thousands of years into the future as they spread through the galaxy? And what would they do to the galaxy - with the power of self replicating machines, and able to make new biological entities and cyborgs etc etc?
It seems like a future that would turn the galaxy into many factions of beings that to us would be like the alien monsters of sci. fi - with obscure purposes and quite possibly come back and destroy the Earth..
Maybe there is some way to prevent us from doing this and colonize the galaxy sensibly and safely.
But - the more I think about it - and since nobody has come up with any convincing answers to this when I raise the issue - I suspect that any sensible ET will choose not to colonize the galaxy, only explore it.
I think - still just as a hypothesis of course - that only reckless short sighted ETs choose to colonize the galaxy. And that any ETS as reckless as that - I think probably destroy all their space colonies in their home planet solar system, long before they have a chance even to attempt their first interstellar mission.
Which might be why there are no ETs here already. Otherwise, surely by now, someone would have decided to colonize the galaxy and they would be here already. That's my favoured solution to the Fermi's paradox.
Which doesn't mean that the "sensible ETs" have to stay at home. They would explore the galaxy as much as they like - that's not a problem so long as they don't set up colonies wherever they go. But there probably aren't that many of them - nearest adventurous explorer could easily be hundreds, or even thousands of light years away and not yet received our radio transmissions - or messages from whatever probes they might have left in our solar system.
Or we might be the first ETs to evolve to technology in our galaxy - if so need to be especially careful how we proceed.
Or - might be that there is a safe and responsible way to colonize a galaxy without excessive risk to yourself and all the other ETs in the galaxy. But if so, I've no idea what it is - and not come across anyone else who has an answer that's at all convincing. Maybe some day we will find that answer though. It might require changes in ourselves and how we behave.
See also: Robert Walker's answer to What is your preferred answer to the Fermi paradox?
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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