Earth-sized planet found in Proxima Centauri's habitable zone

[Zeropoint]

No, it's not. That trillion dollars would have to come from somewhere - we can't even all agree that people deserve to not starve to death, and you want to spend a huge sum of money on something that will accomplish exactly no practical aims and will take centuries?

Well, we've spent about two trillion dollars on the war in Iraq, and that hasn't really accomplished anything practical. I don't know about you but I'd rather have an interstellar mission than a war.

[Adam Reynolds]

And how exactly would that have occurred? Sapient life would have to evolve VERY fast for that to be a thing, because oil is largely the product of plants being crushed by millions of years of high pressure. For there not to be significant oil reserves, sapient species would have had to evolve in the Devonian or earlier.

I am not sure why, but I have had the idea that this would be possible. Looking at a chart of the timeline of evolutionary history it really wouldn't make much sense. Glad to learn something new.

Tides are not a requisite for life, or a movement of that life onto land. Period.

It isn't required, but did it not play a role?

[Esquire]

No, it's not. That trillion dollars would have to come from somewhere - we can't even all agree that people deserve to not starve to death, and you want to spend a huge sum of money on something that will accomplish exactly no practical aims and will take centuries?

Well, we've spent about two trillion dollars on the war in Iraq, and that hasn't really accomplished anything practical. I don't know about you but I'd rather have an interstellar mission than a war.

And so would I. But the Iraq War was supposed to cost much, much less than that, and was supposed to achieve practical ends. Don't be obtuse.

[The Romulan Republic]

Exploring and colonizing an entire new world isn't a practical end?

[Rhadamantus]

For a society even somewhat more advanced than us, that's cheap for the opportunity to colonize an entire solar system.

Why bother? It will most likely be an extremely long time yet before the Solar System is tapped out, and it's not like the Alpha Centauri colony is going to be sending stuff back in a timely fashion (if at all), so the investment is a total loss from the perspective of the the investing entity. A sufficiently wealthy civilization might do some interstellar exploration out of curiosity, and you might even have eccentric space quadrillionaires doing colonization as a 'because we can' vanity project, but I don't think it's a given that interstellar colonization will be of huge interest.

People in and off themselves generate value. It's not a coincidence that the rate of technological progress tracks with population.

[Broomstick]

Exploring and colonizing an entire new world isn't a practical end?

Depends on how you define "practical".

[Alyrium Denryle]

And how exactly would that have occurred? Sapient life would have to evolve VERY fast for that to be a thing, because oil is largely the product of plants being crushed by millions of years of high pressure. For there not to be significant oil reserves, sapient species would have had to evolve in the Devonian or earlier.

I am not sure why, but I have had the idea that this would be possible. Looking at a chart of the timeline of evolutionary history it really wouldn't make much sense. Glad to learn something new.

Tides are not a requisite for life, or a movement of that life onto land. Period.

It isn't required, but did it not play a role?

Not that anyone knows, no. Lots of living things right now depend on tides, but that is because tides predate them. Without tides.. meh. Exploiting an intertidal zone niche might be one of many things that got some organisms onto land, but so would swimming up river and experiencing post-flood drying, or just hanging out in the splash zone. All that is required even for plant life is a selective pressure that drives an organism out of the water. Competition or predation will do it with or without an intertidal zone.

[Kingmaker]

For a society even somewhat more advanced than us, that's cheap for the opportunity to colonize an entire solar system.

Why bother? It will most likely be an extremely long time yet before the Solar System is tapped out, and it's not like the Alpha Centauri colony is going to be sending stuff back in a timely fashion (if at all), so the investment is a total loss from the perspective of the the investing entity. A sufficiently wealthy civilization might do some interstellar exploration out of curiosity, and you might even have eccentric space quadrillionaires doing colonization as a 'because we can' vanity project, but I don't think it's a given that interstellar colonization will be of huge interest.

People in and off themselves generate value. It's not a coincidence that the rate of technological progress tracks with population.

I don't necessarily disagree, but I'm not sure how we get from "people generate value" to "let's pack them into a giant tin can and send them on a century-long one-way trip." The economic value to a Solar Civilization of a colony in the Alpha Centauri system is essentially nil without a way to exchange resources, so it would make more sense to use those resources for local development. As I said, an exploratory mission is not out of the question, and in a sufficiently wealthy civilization it might be a project undertaken by private citizens, but, without some kind of FTL or a radical shift in time scales of interest, there's not going to be much impetus to try and exploit interstellar resources.

[Rhadamantus]

Why bother? It will most likely be an extremely long time yet before the Solar System is tapped out, and it's not like the Alpha Centauri colony is going to be sending stuff back in a timely fashion (if at all), so the investment is a total loss from the perspective of the the investing entity. A sufficiently wealthy civilization might do some interstellar exploration out of curiosity, and you might even have eccentric space quadrillionaires doing colonization as a 'because we can' vanity project, but I don't think it's a given that interstellar colonization will be of huge interest.

People in and off themselves generate value. It's not a coincidence that the rate of technological progress tracks with population.

I don't necessarily disagree, but I'm not sure how we get from "people generate value" to "let's pack them into a giant tin can and send them on a century-long one-way trip." The economic value to a Solar Civilization of a colony in the Alpha Centauri system is essentially nil without a way to exchange resources, so it would make more sense to use those resources for local development. As I said, an exploratory mission is not out of the question, and in a sufficiently wealthy civilization it might be a project undertaken by private citizens, but, without some kind of FTL or a radical shift in time scales of interest, there's not going to be much impetus to try and exploit interstellar resources.

Colonizing Alpha Centauri would triple our resources, and therefore our possible population. More people means faster technological progress.

[Broomstick]

Colonizing another system only increases the resources of the home system (or any other system, for that matter) ONLY if those resources can be shipped to other systems in a reasonable amount of time. Absent FTL drives, that is NOT the case. I can't think of a single resource so scarce it makes sense to travel light years to obtain it. Hence, the unobtainium in the movie Avatar, a useful substance that simply did not exist in the Sol system.

With STL transport, there are only the following reasons to attempt to colonize in another star system:

- fleeing oppression and/or genocide (which leaves the question of how an oppressed group is going to pay for a colony ship/habitat to get there)

- setting up an alternative society (they'll have to find an obscenely wealthy sponsor, which will be hard, because in general the obscenely wealthy are OK with the society they're in. Not always, there are exceptions, but they're rare)

- getting rid of surplus population (most commonly seen in the South Pacific - put the surplus in boats and send them off, maybe they find a new place to live, but to some extent Europe during the great era of colonization) or getting rid of undesirables, such as criminals (North America until the US revolution, Australia after that)

- "lifeboat" for humanity - you set up a colony so that if disaster strikes the home planet/system humanity still survives elsewhere

Looking back in history, the first three reasons did result in new human colonies. It was not as common as the for-profit motive (such as gold fever) or the conquer-new-territory motive (which gets back into shipping resources home, at least some of the time) but neither of those two more-common motives will happen without FTL. Reason three - too many people - won't happen for a long time because we'd have to fill up the Solar system first, and that will take awhile (filling up the Earth just means we move into the rest of the Solar system, it's hella easier to get to). The lifeboat reason is a relatively new one.

So I could see an obscenely wealthy eccentric funding an extra-solar colony (rather like Richard Branson is trying to get into commercial space tourism, though it's not an exact parallel, and likewise other contemporary space entrepreneurs), either as a lifeboat or due to whacky religious/political/social ideas. (The US State of Pennsylvania was arguably one of the largest of the latter, when William Penn acquired a tremendously large tract of land in North America he set it up as a refuge for Quakers).

Here's the problem, though - even on Earth, where you didn't have to worry about taking your air with you, and the journeys were only months long (not decades or centuries) there was a significant fatality rate in just getting to the "New World" (or island, or whatever). Then, even without the worry of "can we even eat anything we find growing there?" or "can we grow food there?", or the even more basic "can we breathe the air?" there were still high fatality rates for new colonies.

You're going to get failed/extinct colonies, even with the most sophisticated and well-planned "lifeboat" attempts. Add in the whackjobs seeking a personal paradise (if that even happens) and things really get rough - most of those attempts did not end well.

To get to a new planet, the logistics of the trip are staggering. A random space rock you miss heading at you can wreck everything /kill everyone. When you finally get where you're going, what will you find there? If there's life, is it compatible with us or will everything be poisonous to us (or vice versa)? Are there environmental toxins present we'll need to deal with? Micronutrient deficiencies? How much will we know about natural hazards? (will there be tornadoes like the Great Plains of North America? Earthquakes and volcanoes like Japan?) There will be a very small human population (possibly not even the minimum to preserve genetic diversity, a colony attempt might be a limited number of people with genetic diversity supplied by banked sperm, possibly eggs as well) and NO hope of rescue or aid from outside. Nevermind the problem of maintaining a technological society - on Earth, colonies could revert to stone-age tech and still survive (there's some evidence the Native Tasmanians regressed quite a bit technologically compared to the Australian Natives... which weren't exactly known to be high-tech, either) but on an alien world? Presumably there are rocks you can knap but unless the plants/animals/whatevers are compatible with human biology reverting to the stone age likely means every starves, is poisoned, or dies of some weird nutritional deficiency. Or even all three at the same time. Not to mention needing power to preserve banked genetic material until your population becomes sufficiently large to be self-sustaining in regards to genetic diversity - remember, you're going to have a high fatality rate due to ignorance of the environment and limited medical resources in addition to the usual problems of illness, people going whack and committing murder, etc. The required birth rate for such a colony is higher than for a large, stable society. If the environment is extreme enough you'll get some pretty severe selective pressures operating. (This does mean that far enough down the line different human colonies are going to wind up as different human species due to genetic drift, selection, and being very isolated breeding populations).

Bottom line, colonizing another star system is a high risk, high cost endeavor. That doesn't rule it out, but it does mean it's not automatic and probably not very common.

[Esquire]

Exploring and colonizing an entire new world isn't a practical end?

Not in my mind - my* grandchildren will be long dead before we even know if the mission succeeded, and it's effectively impossible for any financial return on investment to make its way back to Earth. You can certainly argue that humanity as a species being more widespread is a good thing, but that's definitely not a practical concern on any normal scale. Do you disagree?

*Here meaning 'a person considering spending a trillion dollars on interstellar missions,' not me personally.

[Ziggy Stardust]

Colonizing Alpha Centauri would triple our resources, and therefore our possible population. More people means faster technological progress.

How would it triple our resources? Which resources, precisely, are you even talking about? How would those resources be utilized back on Earth if they are all the way on Alpha Centauri, anyway? (How did you manage to ignore that point despite it being raised like 6 fucking times in this thread?)

Life isn't like a strategy game, where you have a counter that tallies how many total resources you have, which you can then use to upgrade your cities or whatever. There are pretty massive logistical burdens that would have to be overcome to make any resources from Alpha Centauri exploitable for Earth in any direct and meaningful sense, and it isn't clear that any of it is even close to feasible without FTL.

[The Romulan Republic]

Exploring and colonizing an entire new world isn't a practical end?

Not in my mind - my* grandchildren will be long dead before we even know if the mission succeeded, and it's effectively impossible for any financial return on investment to make its way back to Earth. You can certainly argue that humanity as a species being more widespread is a good thing, but that's definitely not a practical concern on any normal scale. Do you disagree?

*Here meaning 'a person considering spending a trillion dollars on interstellar missions,' not me personally.

Personally, I would argue that something can have benefits that make it worthwhile for society to invest in without personally/financially benefitting from it.

And I don't think you really can put a price tag on a whole new world.

Although their could be considerable short-term gains for whichever nation or nations did it in the form of economic stimulus, technological spin-offs, and a way to re-employ elements of the military-industrial complex.

Plus prestige/bragging rights, of course.

[Simon_Jester]

Honestly, I think the kind of society most likely to go interstellar with sublight drives would be one that has long since transitioned into a model dominated by artificial space habitats, with hundreds or thousands of large space stations or hollow asteroids that have sustainable populations. Once you've done that, you can start thinking seriously about what it would take to take one of those big stations and outfit it for a hundred year voyage to another solar system. And what you'd have to pack for the trip to avoid dependency on any imported goods.

In which case they're not thinking of colonizing Alpha Centauri's planets. They're after the system. And the most likely motivation would be something like "our asteroid habitat is tired of being pushed around by other asteroid habitats, so screw you guys, we're going home to the next star!"

This also resolves a lot of the "can we even live there" considerations, because these are people who are accustomed to building their own environment in totally uninhabitable space out of resources that are almost guaranteed to be available around Alpha Centauri (rocks and ice, for instance).

[Eternal_Freedom]

And now I really do want to go and find the equations to calculate the delta-v needed for a one-way trip to Proxima orbit.

[EnterpriseSovereign]

More people means faster technological progress.

That's incredibly simplistic, to put it mildly.If more population was engaged in science/engineering/whatever, tech would progress, but with half the population of the planet living in poverty and simply struggling for survival for one reason or another (overpopulation/famine/war/etc) it's demonstrably not the case.

More population is only going to be useful if you can support them such that they have a net contribution to society relative to living costs.

[Rhadamantus]

More people means faster technological progress.

That's incredibly simplistic, to put it mildly.If more population was engaged in science/engineering/whatever, tech would progress, but with half the population of the planet living in poverty and simply struggling for survival for one reason or another (overpopulation/famine/war/etc) it's demonstrably not the case.

More population is only going to be useful if you can support them such that they have a net contribution to society relative to living costs.

Yes, hence why I'm not saying we should colonize now. In a hundred years, it makes a lot more sense.

[Rhadamantus]

Colonizing Alpha Centauri would triple our resources, and therefore our possible population. More people means faster technological progress.

How would it triple our resources? Which resources, precisely, are you even talking about? How would those resources be utilized back on Earth if they are all the way on Alpha Centauri, anyway? (How did you manage to ignore that point despite it being raised like 6 fucking times in this thread?)

Life isn't like a strategy game, where you have a counter that tallies how many total resources you have, which you can then use to upgrade your cities or whatever. There are pretty massive logistical burdens that would have to be overcome to make any resources from Alpha Centauri exploitable for Earth in any direct and meaningful sense, and it isn't clear that any of it is even close to feasible without FTL.

The number of people that could live in the solar system is less than the number than could live in the solar system+alpha centauri.

[Simon_Jester]

And now I really do want to go and find the equations to calculate the delta-v needed for a one-way trip to Proxima orbit.

That depends almost entirely on when you want to get there. You can breeze your way up to solar escape velocity, leave the solar system at a double-digit number of kilometers per second (like the Pioneer, Voyager, and New Horizons probes), and then gently brake into an orbit around Proxima Centauri... but you'd take millenia to get there.

The delta-v required to escape solar orbit, and then decelerate to enter Alpha Centauri C orbit, is miniscule compared to the speed you need to make the trip in a reasonable timeframe (and slow back down afterwards).

[Guardsman Bass]

Honestly, I think the kind of society most likely to go interstellar with sublight drives would be one that has long since transitioned into a model dominated by artificial space habitats, with hundreds or thousands of large space stations or hollow asteroids that have sustainable populations. Once you've done that, you can start thinking seriously about what it would take to take one of those big stations and outfit it for a hundred year voyage to another solar system. And what you'd have to pack for the trip to avoid dependency on any imported goods.

In which case they're not thinking of colonizing Alpha Centauri's planets. They're after the system. And the most likely motivation would be something like "our asteroid habitat is tired of being pushed around by other asteroid habitats, so screw you guys, we're going home to the next star!"

They could even potentially "island hop" in space, migrating from one Oort Cloud body to the next gathering resources - and then cross over to Alpha Centauri's Oort Cloud equivalent (if it has one) and do the same on their way to the star system there. Once you have habitats that have accepted relying entirely on nuclear power and extremely long travel/communication times with the main civilization back here in the solar system, it's fairly straightforward.

. . . In practice, I tend to think that's going to be rare. If we do fill out space habitats, most of them will probably stay in the inner solar system where they can be in close communication with people back on Earth while utilizing cheap solar power.

[Alyrium Denryle]

Colonizing Alpha Centauri would triple our resources, and therefore our possible population. More people means faster technological progress.

How would it triple our resources? Which resources, precisely, are you even talking about? How would those resources be utilized back on Earth if they are all the way on Alpha Centauri, anyway? (How did you manage to ignore that point despite it being raised like 6 fucking times in this thread?)

Life isn't like a strategy game, where you have a counter that tallies how many total resources you have, which you can then use to upgrade your cities or whatever. There are pretty massive logistical burdens that would have to be overcome to make any resources from Alpha Centauri exploitable for Earth in any direct and meaningful sense, and it isn't clear that any of it is even close to feasible without FTL.

The number of people that could live in the solar system is less than the number than could live in the solar system+alpha centauri.

You missed his point. It would take, at best, a century to get there if we went balls-deep with a fusion drive and a small payload. We are nowhere near the point of a generation ship.

There is simply no practical way to exploit that star system. There is a fuckton of empty space and resources in just this solar system, and much more accessible to boot. Direct economic gain is not the argument you want to make.

The correct argument is that it would be Fucking Awesome and we should go there because We Can (in the not unforseeable future). There is nothing practical about it. We go because we want to.

And now I really do want to go and find the equations to calculate the delta-v needed for a one-way trip to Proxima orbit.

Delte-v is just the velocity you want.

You mean energy,thrust, and remass requirements, which take into account things like payload and desired acceleration. I can probably do the math if you want. Say, for the Space Battleship Yamato at a constant acceleration of 1 G?

Just looking over that, JUST the energy requirements are going to require fusing several million tons of deuterium. Ummmm. OK. Something a bit less massive than the Yamato...

Pick a favorite warship, I suppose. The Space Destroyer Escort Samuel B. Roberts perhaps?

[Guardsman Bass]

All this talk of fusion rockets has made me remember that I've never read a space-heavy science fiction story where they turned out to be infeasible or impractical for space travel and power generation. They're just assumed to be down the line at some point. Aside from Orion-style stuff, it could be they just never pan out in a useful way - certainly the examples of fusion power we have from nature (AKA stars) are not impressive in their energy efficiency.

[Simon_Jester]

They could even potentially "island hop" in space, migrating from one Oort Cloud body to the next gathering resources - and then cross over to Alpha Centauri's Oort Cloud equivalent (if it has one) and do the same on their way to the star system there. Once you have habitats that have accepted relying entirely on nuclear power and extremely long travel/communication times with the main civilization back here in the solar system, it's fairly straightforward.

Although Oort Cloud objects are likely to be sparse and poor enough that it won't be very helpful to do this, in my opinion.

. . . In practice, I tend to think that's going to be rare. If we do fill out space habitats, most of them will probably stay in the inner solar system where they can be in close communication with people back on Earth while utilizing cheap solar power.

Well yes, it's the "screw you guys, we want out of here" people who will leave, as always. The point is simply that long distance colonization is ALWAYS more possible in a world where people routinely travel and live independently of the 'home.'

Right now we're in the position of talking about colonizing a new continent in a world that has no ships. Of course it seems implausible, how could anyone ever swim for thousands of miles across the ocean to reach the new continent alive? How would they bring all the tools people need to get there; anyone carrying all that metal would sink and drown!

But we can imagine a future state of affairs where the colonization is possible, or even possible without any disproportionate difficulty by the standards of the whole civilization...

[Rhadamantus]

How would it triple our resources? Which resources, precisely, are you even talking about? How would those resources be utilized back on Earth if they are all the way on Alpha Centauri, anyway? (How did you manage to ignore that point despite it being raised like 6 fucking times in this thread?)

Life isn't like a strategy game, where you have a counter that tallies how many total resources you have, which you can then use to upgrade your cities or whatever. There are pretty massive logistical burdens that would have to be overcome to make any resources from Alpha Centauri exploitable for Earth in any direct and meaningful sense, and it isn't clear that any of it is even close to feasible without FTL.

The number of people that could live in the solar system is less than the number than could live in the solar system+alpha centauri.

You missed his point. It would take, at best, a century to get there if we went balls-deep with a fusion drive and a small payload. We are nowhere near the point of a generation ship.

There is simply no practical way to exploit that star system. There is a fuckton of empty space and resources in just this solar system, and much more accessible to boot. Direct economic gain is not the argument you want to make.

The correct argument is that it would be Fucking Awesome and we should go there because We Can (in the not unforseeable future). There is nothing practical about it. We go because we want to.
?

You underestimate exponential growth. The highest number I've seen for possible solar population is 10^22 people (starlift the sun, and slowly turn it into habitats). Assuming the current population growth rate, it'd take us 4000 years to fill the solar system. If we go with a more reasonable estimate, it'd take just 1700 years.

[Ziggy Stardust]

The number of people that could live in the solar system is less than the number than could live in the solar system+alpha centauri.

Are you fucking illiterate or something?

You keep completely ignoring everybody's points and saying, "lol population growth". Once, again: life is not an RTS. Harvested resources don't go into a magic universal pool that can be accessed from anywhere, and collecting X pieces of gold doesn't let you magically upgrade to the next technology level. If Alpha Centauri were colonized, that population would be COMPLETELY AND FUNCTIONALLY SEPARATE FROM THAT OF THE SOLAR SYSTEM. It would have precisely 0 economic impact on the Solar System (notwithstanding the cost of sending the expedition out to begin with).