# Alpha Centauri might be habitable after all



## Brian G Turner (Jun 12, 2018)

A long-term study of Alpha Centuari has dispelled fears that life couldn't survive in that star system.

NASA's Chandra X-ray Observatory made observations every six months from 2005, and discovered that the radiation wouldn't be so bad as originally expected.

At around 4 light years away, Alpha Centauri is the nearest star system to Earth. It comprises three stars: Alpha Centuari A, which is very similar to our sun; and Alpha Centuari B, which is a smaller star that orbits it to form a binary pair. At a very extended orbit around both is the small red dwarf Proxmia Centauri.

Originally it was thought that interactions between Alpha Centuari A and B would result in a flood of radiation that could sterilize any nearby planets. Although no planets have _yet _been found around these two stars, data from Chandra shows that radiation levels are actually similar to our own system.

So if any planets a safe distance from those stars might be capable of supporting life - not just indigenous where conditions allow, but also future colonists from Earth.

However, it's not all good news - Promixa was found to emit deadly bursts of X-Rays during solar flares during its solar cycle. This does not bode well for Proxima b, a rocky planet about the size of Earth that has already been detected in orbit around Proxima, in what should have been a habitable zone.

There remains hope for the future, though - the James Webb telescope will take a closer look for planets in the Alpha Centuari system, after it launches in 2020.

Additionally, the race is on to design a space probe capable of visiting Alpha Centauri, with the private company Breakthrough Starshot aiming to have a viable project "within a generation", while NASA is also looking to send its own interstellar probe there in 2069.

_[IMAGE: Alpha Centuari A and B are so close that they appear as one star in the above image, with Proxima circled red.]_


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## SilentRoamer (Jun 12, 2018)

The discussion of "habitable" bothers me. Habitable by whom? The single example of life we have at the moment? Such a large sample of 1!

Maybe a lot more radiation is conducive to whatever life form may or may not be out there.

It reminds me of the novel Wheelers - where some Jovian blimps sit and think how awful life must be for anything developing on "Blue Poison" with water and oxygen being highly poisonous to their own life.

I would hope that when we do find life, it is varied and interesting by equal measures, in all likelihood I expect most life dies at the bottom of its own gravity well. I think a truly advanced species might necessarily be spacebound already.

Thanks Brian I found this very interesting.


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## night_wrtr (Jun 12, 2018)

SilentRoamer said:


> Maybe a lot more radiation is conducive to whatever life form may or may not be out there.



Good point, and I agree that whats harmful to us could be required for life's survival elsewhere.



SilentRoamer said:


> I would hope that when we do find life, it is varied and interesting by equal measures, in all likelihood I expect most life dies at the bottom of its own gravity well. I think a truly advanced species might necessarily be spacebound already.



I guess that depends where on the life scale The Great Filter falls. It may get us all at some point, but its hard not to think there are at least a few Type 1 or 2 civilizations out there.


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## Brian G Turner (Jun 12, 2018)

SilentRoamer said:


> The discussion of "habitable" bothers me. Habitable by whom? The single example of life we have at the moment? Such a large sample of 1!



Well, if we ever do start colonizing space and need a base at Alpha Centauri, at least we don't need to fear being irradiated by the local binary stars. 

But I do agree - life constantly surprises us - but the world of science tends to dislike speculation without supporting data, so we're stuck with our limited sample until we're able to broaden it. Hopefully future research on icy moons around Jupiter and Saturn will help with that.


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## night_wrtr (Jun 12, 2018)

Brian G Turner said:


> Well, if we ever do start colonizing space and need a base at Alpha Centauri, at least we don't need to fear being irradiated by the local binary stars.



I am a little disheartened that it will be so many years before we send something in that direction. Still, it would be out of our lifetimes more than likely before we came near the system. 

Even Laser Sails would take a 100 years? Is there any plan to create a telescope like Hubble or James Webb and launch it like a probe into deep space? For instance, if we wanted to scout Alpha Centauri, I would think that the time investment to get clearer images would have a large payoff for the increase in detail it could find as it came nearer to the system.


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## Onyx (Jun 12, 2018)

Given how close B gets in one part of its orbit, I would think life on the planet would have to be awful flexible to put up with the orbital shifts and extra light of second full sized sun passing through the equivalent of Saturn's orbit, but having 1000 times the mass of Jupiter. The whole "three body problem".

It would be an ecological catastrophe every 79 years.


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## BAYLOR (Jun 12, 2018)

Onyx said:


> Given how close B gets in one part of its orbit, I would think life on the planet would have to be awful flexible to put up with the orbital shifts and extra light of second full sized sun passing through the equivalent of Saturn's orbit, but having 1000 times the mass of Jupiter. The whole "three body problem".
> 
> It would be an ecological catastrophe every 79 years.



So basically not ideal for human habitation.


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## Onyx (Jun 13, 2018)

BAYLOR said:


> So basically not ideal for human habitation.


I don't think the habitability being discussed is for earth life. While humans can survive anywhere living in a tube, I'm not so sure that recreating an earth-like environment on a planetary scale is really practical, even if you have the right orbit, day/night cycle, gas mix, magnetosphere, etc.

The planet around Alpha Centauri sounds ideal for breeding life that is extremely hard to kill - like an ocean wide monoculture.


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## BAYLOR (Jun 13, 2018)

Onyx said:


> I don't think the habitability being discussed is for earth life. While humans can survive anywhere living in a tube, I'm not so sure that recreating an earth-like environment on a planetary scale is really practical, even if you have the right orbit, day/night cycle, gas mix, magnetosphere, etc.
> 
> The planet around Alpha Centauri sounds ideal for breeding life that is extremely hard to kill - like an ocean wide monoculture.



It's going to centuries before we ship to Alpha Centauri to find out.


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## Onyx (Jun 13, 2018)

BAYLOR said:


> It's going to centuries before we ship to Alpha Centauri to find out.


That seems like a rather long time, considering.


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## BAYLOR (Jun 13, 2018)

Onyx said:


> That seems like a rather long time, considering.



Possible  mode of transportation .
1.  Multigenerational ship 
2. Sleeper ship with in crew in suspended animation .
 Both concepts are well beyond  technological means and probably  will be for another 2 centuries .


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## Onyx (Jun 13, 2018)

BAYLOR said:


> Possible  mode of transportation .
> 1.  Multigenerational ship
> 2. Sleeper ship with in crew in suspended animation .
> Both concepts are well beyond  technological means and probably  will be for another 2 centuries .


Yeah, no idea where you pull these prognostications from.


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## BAYLOR (Jun 13, 2018)

Onyx said:


> Yeah, no idea where you pull these prognostications from.



From my imagination .


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## night_wrtr (Jun 13, 2018)

BAYLOR said:


> Possible  mode of transportation .
> 1.  Multigenerational ship
> 2. Sleeper ship with in crew in suspended animation .
> Both concepts are well beyond  technological means and probably  will be for another 2 centuries .



I would imagine multi-generational ships would come long after we develop more advanced engines, though. Once we have a ship that is capable of travelling faster and more efficiently, then that aspect would probably come into play. 

And I say that because if we send a multi-generational ship to A.C., but perfect Laser Sails, or some other engine technology later on that gets us further up the speed of light %, a faster ship could be launched decades later and reach the destination before the first ever does.


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## johndsal (Jun 13, 2018)

If we do find life on other worlds, how can we justify colonizing such a planet just because it is suitable for our species. We would be a little upset if the same thing happened to us here on Earth. The only answer is to find a totally uninhabited world and terraform. Difficult yes but we should not assume we have the right to expand humanity by usurping worlds with their own indigenous life.


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## Onyx (Jun 13, 2018)

johndsal said:


> If we do find life on other worlds, how can we justify colonizing such a planet just because it is suitable for our species. We would be a little upset if the same thing happened to us here on Earth. The only answer is to find a totally uninhabited world and terraform. Difficult yes but we should not assume we have the right to expand humanity by usurping worlds with their own indigenous life.


Would you consider bacteria or even plant life 'inhabited'. What are the ethical barriers to putting un-self aware life in a conservatory and repurposing their former territory?


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## BAYLOR (Jun 14, 2018)

johndsal said:


> If we do find life on other worlds, how can we justify colonizing such a planet just because it is suitable for our species. We would be a little upset if the same thing happened to us here on Earth. The only answer is to find a totally uninhabited world and terraform. Difficult yes but we should not assume we have the right to expand humanity by usurping worlds with their own indigenous life.



Even if we did find such a world, we would never be able to walk on it without space suits. We couldn't breath the air because in all likelihood , the native viruses and the bacteria could prove lethal to us. Also any viruses or bacteria that we carry could  likewise prove to be lethal  to whatever lifeforms are living on the planet.


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## Onyx (Jun 14, 2018)

BAYLOR said:


> Even if we did find such a world, we would never be able to walk on it without space suits. We couldn't breath the air because in all likelihood , the native viruses and the bacteria could prove lethal to us. Also any viruses or bacteria that we carry could  likewise prove to be lethal  to whatever lifeforms are living on the planet.



Why would alien life even have viruses that could interact with DNA based earth life? That's like saying your DVD player is going to catch a computer virus from you smartphone.


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## Brian G Turner (Jun 14, 2018)

Onyx said:


> Why would alien life even have viruses that could interact with DNA based earth life?



If it's based on the same or similar amino acids, then that would definitely be a possibility. There seems no reason at the moment to presume that life on Earth is the biological exception in the universe.


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## Onyx (Jun 14, 2018)

Brian G Turner said:


> If it's based on the same or similar amino acids, then that would definitely be a possibility. There seems no reason at the moment to presume that life on Earth is the biological exception in the universe.


I don't think we're the exception, but I think the chances that virus would be able to co-opt the functions of a cell it isn't programmed for are close to zero. We use the same DNA as trees, but very few viruses can infect either. Aliens made of the same amino acids might end up with something very similar to DNA, but to end up with cell structures that function like earth life is a stretch, and compatible cell structure to carry out the reproduction instructions that make viruses dangerous even more unlikely.

DNA is like binary, how the DNA spells things is like Fortran and what the Fortran program says is like an operating system. For an alien virus to infect us they would need to not just use DNA, but happen to be coded to work with operating systems that use ribosomes, permeable lipid cell walls, ATP for energy, etc.

The reality is that DNA based life might not have a cellular structure at all. Like an ostrich egg, alien life forms could be large organisms that appear to be a single cell. They could have "cell" walls made of calcium rather than lipids. There is nothing about DNA that means that it needs to encode life remotely like ours, just be made of similar ingredients.

That's why a remain doubtful that viruses - which reproduce entirely by subverting our system program - are likely to work in any sort of universal way - there are too many orders of magnitude of necessary parallelism in the evolution to have that kind of compatibility. Which is very similar to how even members of the same genus can't generally be crossbred - even small differences matter.

I am of the mind that 'anything is possible', but the level of interactivity necessary for alien viruses to commandeer and reprogram our cells seems outlandishly unlikely. Billions to one. Like me reproducing with a dandelion. 

A flesh eating 'bacteria-like lifeform' would be more of a concern, because that just requires us to be roughly digestible into useful compounds before whatever incompatible toxins (if any) slow the replication or growth of the infection. But that's a simpler process more like rot or digestion.


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## johndsal (Jun 14, 2018)

Bacteria and plant life on another planet indeed means it is inhabited. We could never know if it was sentient because they may have a means of communication we do not yet understand. Also, as life on Earth has evolved from bacteria, so might the life forms on another world evolve. We should not assume that any planet is ours to colonise because the life we find there is not as advanced as we think we are. As I said before, how would we feel?


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## Vertigo (Jun 14, 2018)

We go to a lot of effort to try and prevent exploitation of sensitive environments on our own planet. NASA has teams dedicated to preventing contamination of other planetary environments visited by our probes and not just to avoid the risk of misinterpreting our own biology for extra-terrestrial biology, but rather because of the ethical issues of such contamination. There's no reason to think we wouldn't make equally strenuous efforts regarding an exoplanet discovered to have life.

All that said, our efforts to protect our own native environments have not exactly been a spectacular success; there are always plenty of people who strive to exploit any environment that might show a profit and there's no reason not to expect the same to be true with regard to exoplanets.


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## Brian G Turner (Jun 14, 2018)

Onyx said:


> Why would alien life even have viruses that could interact with DNA based earth life?



Why not?


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## johndsal (Jun 14, 2018)

What happens if we arrive at a planet that has a fairly advanced civilisation? Do we rely on their good nature to allow us to settle there? Do we try and take it by force because we could be the losers. If we are there because we are trying to save the human race, we cannot put the future of our species at risk by going to one planet. That means finding other alternatives and that is why I feel terraforming is the answer. Admittedly it would be expensive, technically difficult and take millennia.


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## Vertigo (Jun 14, 2018)

johndsal said:


> What happens if we arrive at a planet that has a fairly advanced civilisation? Do we rely on their good nature to allow us to settle there? Do we try and take it by force because we could be the losers. If we are there because we are trying to save the human race, we cannot put the future of our species at risk by going to one planet. That means finding other alternatives and that is why I feel terraforming is the answer. Admittedly it would be expensive, technically difficult and take millennia.


I would hope we wouldn't attempt to take it by force but I wouldn't bet on it. If the other civilisation is 'friendly' and the future of the human species is at risk then maybe we could leave a small colony with them whilst we look for other alternatives; more than one basket for our eggs.


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## night_wrtr (Jun 14, 2018)

johndsal said:


> What happens if we arrive at a planet that has a fairly advanced civilisation? Do we rely on their good nature to allow us to settle there? Do we try and take it by force because we could be the losers.



I hate to say this, but humanity doesn’t have a very good track record for politely asking for settlements. If we did find an advanced civilization on another planet, I truly hope that our species has developed a better common morality, but I find it hard to believe, in a situation where humans are looking to survive by relocation, we wouldn’t repeat history.


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## Vertigo (Jun 14, 2018)

Sadly if it came down to a truly "us or them" scenario I really can't see us humans quietly going off into space to die out of sight, and in fact in such a scenario I'm not sure which side of the fence I'd be, if there is truly no chance of cohabitation. It's an interesting moral dilemma and one touched on in many SF books including my recent reading of both Children of Time and All these Worlds - in the former we manage to cohabit, in the latter we are forced to exterminate.


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## night_wrtr (Jun 14, 2018)

The same can be said in reverse. Would we be willing to allow settlement on our planet? It's (probably true across all galactic civilizations should there be others) in our nature to self-preserve at whatever means necessary. 

Haven't read those, but Children of Time looks like an interesting premise.


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## johndsal (Jun 14, 2018)

Could we convince the natives that we come in peace? Could we be convinced if they came to us? From what I have heard lately, most scientists, astronomers etc think that the only surviving entities throughout the universe will be artificial life forms that will see us as we see insects


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## Vertigo (Jun 14, 2018)

night_wrtr said:


> The same can be said in reverse. Would we be willing to allow settlement on our planet? It's (probably true across all galactic civilizations should there be others) in our nature to self-preserve at whatever means necessary.
> 
> Haven't read those, but Children of Time looks like an interesting premise.


Children of Time by Adrian Tchaikovsky is a very good serious bit of hard SF, All these World is the last in our very own @Dennis E. Taylor's Bobiverse trilogy (leastways I think it's the last), slightly less serious hard SF in the sense that the Martian is slightly less serious hard SF ie. serious but lots of snarky humour in it.


johndsal said:


> Could we convince the natives that we come in peace? Could we be convinced if they came to us? From what I have heard lately, most scientists, astronomers etc think that the only surviving entities throughout the universe will be artificial life forms that will see us as we see insects


Those, of course, are all the big questions, to which Cixin Liu's The Three Body Problem gives a very depressing answer.


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## Onyx (Jun 14, 2018)

johndsal said:


> What happens if we arrive at a planet that has a fairly advanced civilisation? Do we rely on their good nature to allow us to settle there? Do we try and take it by force because we could be the losers. If we are there because we are trying to save the human race, we cannot put the future of our species at risk by going to one planet. That means finding other alternatives and that is why I feel terraforming is the answer. Admittedly it would be expensive, technically difficult and take millennia.


I think this assumes a rather B-movie type scenario where humans make this spectacular effort to cross some enormous gulf, make no long range flybys and arrive so desperately out of supplies that we have to colonize the planet to survive. The "desperate colonist" trope is a little ridiculous.

If we are actually set up to colonize a planet, we would have tons of supplies. If the planet is in a remotely normal solar system, we can mine raw material and refuel the ship from asteriods, comets, moons, gas giants. If we sent probes ahead we would know that the planet is occupied and might decide not to risk the ship by diverting, since ships really aren't all that tough.

Alien planets are not likely to be easily habitable, and if that's the big plan, then the preparations and alternatives to that plan are going to exist in depth. It isn't going to be like rushing off the plane when it lands in Fiji.


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## night_wrtr (Jun 15, 2018)

Vertigo said:


> Those, of course, are all the big questions, to which Cixin Liu's The Three Body Problem gives a very depressing answer.



well, there is another book added to my list. 



Onyx said:


> I think this assumes a rather B-movie type scenario where humans make this spectacular effort to cross some enormous gulf, make no long range flybys and arrive so desperately out of supplies that we have to colonize the planet to survive. The "desperate colonist" trope is a little ridiculous.



Maybe, but this is because humanity seems like it is headed for some kind of catastrophe at all times. Whether we are just capable of sending ships into space or ready to colonize, it is a method that works because audiences like it and it seems like a real scenario. 



Onyx said:


> If we are actually set up to colonize a planet, we would have tons of supplies. If the planet is in a remotely normal solar system, we can mine raw material and refuel the ship from asteriods, comets, moons, gas giants. If we sent probes ahead we would know that the planet is occupied and might decide not to risk the ship by diverting, since ships really aren't all that tough.



In the best case scenario, this makes sense. But when is it ever the best case?


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## Onyx (Jun 15, 2018)

night_wrtr said:


> well, there is another book added to my list.
> 
> 
> 
> ...


How is a worst case scenario ship crew going to make a planet habitable for earth life?


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## night_wrtr (Jun 15, 2018)

Onyx said:


> How is a worst case scenario ship crew going to make a planet habitable for earth life?



That is an excellent writing prompt.


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## Onyx (Jun 15, 2018)

night_wrtr said:


> That is an excellent writing prompt.


In the story I'm working on the planet was surveyed and seeded hundreds of years ago and is done terraforming. But the ships also were well stocked when they arrived.


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## night_wrtr (Jun 15, 2018)

Onyx said:


> In the story I'm working on the planets was surveyed and seeded hundreds of years ago and is done terraforming. But the ships also were well stocked when they arrived.



We can only hope it goes that smoothly!


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## Onyx (Jun 15, 2018)

night_wrtr said:


> We can only hope it goes that smoothly!


That part will, because that's just background material to explain why the characters have a virgin world to enact their political machinations upon, rather than being about the difficulty of getting there and making it habitable. 

Actually, a story about a crew that spends thousands of years in orbit turning an ice ball into a paradise would be mighty interesting, too. Especially if they can't see spoiling it with people when they're done. I've never seen that, in particular.


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## J Riff (Jun 15, 2018)

There's nothing there. Apparently, the nearest habited place is about 4-5 solar systems away. They have no vacancy though.


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## Mirannan (Jun 15, 2018)

Onyx said:


> Given how close B gets in one part of its orbit, I would think life on the planet would have to be awful flexible to put up with the orbital shifts and extra light of second full sized sun passing through the equivalent of Saturn's orbit, but having 1000 times the mass of Jupiter. The whole "three body problem".
> 
> It would be an ecological catastrophe every 79 years.



Alpha Centauri B is about 90% of the mass of the Sun and roughly half its luminosity. so it wouldn't be quite as bad as that. In addition, if the planet was in the Goldilocks zone for A, it would also be at least ten times closer to A than B. (The minimum distance between A and B is about 11AU.)

So the gravitational influence of B on an Earth-like planet of A would be a maximum of 1/100 of the main sun's gravity - comparable to solar tides on Earth - and the maximum extra light would be 1/200. Which would make for bright nights, no doubt, when B was at its closest, but I don't really think this would be a problem - especially since, of course, life on a planet of A would have evolved under these conditions.

In the case of a planet of B, IMHO the gravitational situation would be actually less disturbed - because a planet of B would have to be closer to its sun because of the lower luminosity. However, the light of A would then be something like 1/50 that of B at most, which is getting significant - but, again, life would have evolved under those conditions.


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## Onyx (Jun 15, 2018)

Mirannan said:


> Alpha Centauri B is about 90% of the mass of the Sun and roughly half its luminosity. so it wouldn't be quite as bad as that. In addition, if the planet was in the Goldilocks zone for A, it would also be at least ten times closer to A than B. (The minimum distance between A and B is about 11AU.)
> 
> So the gravitational influence of B on an Earth-like planet of A would be a maximum of 1/100 of the main sun's gravity - comparable to solar tides on Earth - and the maximum extra light would be 1/200. Which would make for bright nights, no doubt, when B was at its closest, but I don't really think this would be a problem - especially since, of course, life on a planet of A would have evolved under these conditions.
> 
> In the case of a planet of B, IMHO the gravitational situation would be actually less disturbed - because a planet of B would have to be closer to its sun because of the lower luminosity. However, the light of A would then be something like 1/50 that of B at most, which is getting significant - but, again, life would have evolved under those conditions.


I guess I was thinking that with the similarity in mass, L1 between the two suns is going to be around 6 AU, and I could see the planet getting tugged toward L1 on every orbit.

And I said 79 years, but it would be closer to 1 year, assuming the planet was in a similar orbit to ours around Alpha. Maybe that oscillation is minor relative to a yearly cycle. I don't know how much it would change the planet's orbit over time, though.


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## johndsal (Jun 16, 2018)

The other thing to think of is who will go on these trips. Will it be the rich, the military, the scientists, governments? Ordinary folk will be left to their fate. Can we imagine a universe populated with the descendants of politicians, royalty etc. That scares me more than aliens coming here and sharing our planet


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## night_wrtr (Jun 16, 2018)

johndsal said:


> The other thing to think of is who will go on these trips. Will it be the rich, the military, the scientists, governments? Ordinary folk will be left to their fate. Can we imagine a universe populated with the descendants of politicians, royalty etc. That scares me more than aliens coming here and sharing our planet



While I would say that the rich and powerful would probably be able to pull some strings for seats, I’d say that nearly all of the people selected to go would have to have a specific skill set to contribute to the group. At least in the early pioneering days when seats are limited.

And I say selected because there would probably be some kind of pool/lottery that narrows the field down among those competing for jobs.


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## Vertigo (Jun 16, 2018)

night_wrtr said:


> While I would say that the rich and powerful would probably be able to pull some strings for seats, I’d say that nearly all of the people selected to go would have to have a specific skill set to contribute to the group. At least in the early pioneering days when seats are limited.
> 
> And I say selected because there would probably be some kind of pool/lottery that narrows the field down among those competing for jobs.


I would have thought you'd only need a pool lottery approach if you are running away from something with limited 'seats.' Not everyone wants to be a pioneer and I'd think you'd do just fine recruiting the best from across the world.


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## night_wrtr (Jun 16, 2018)

Vertigo said:


> I would have thought you'd only need a pool lottery approach if you are running away from something with limited 'seats.' Not everyone wants to be a pioneer and I'd think you'd do just fine recruiting the best from across the world.



Maybe, but if we think how far into the future these pioneers would start embarking on the first ships, then think about the state of word affairs, living conditions, etc, you might find yourself with more qualified volunteers than you can use. At least in the early days.


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## chornedsnorkack (Jun 17, 2018)

Onyx said:


> And I said 79 years, but it would be closer to 1 year, assuming the planet was in a similar orbit to ours around Alpha. Maybe that oscillation is minor relative to a yearly cycle. I don't know how much it would change the planet's orbit over time, though.


Not all that much.
At periapse, the stars are still 11 AU distance. The period would be 26 Earth years if stars stayed at the same distance, which they do not.

While the orbital period of Ab, in habitable zone, would be 1,3 Earth years.
So 20 orbits in notional circular orbit.
While Moon has about 13 orbits in 1 year.
Sun does perturb orbit of Moon. What happens?
The plane of Moon´s orbit changes rapidly, and so does the apside line.
But the inclination of Moon´s orbit to ecliptic remains small and constant, and the eccentricity varies periodically within small limits.
So, for the planets of Alpha Centauri, I should expect this kind of periodic, small amplitude perturbations.
Any actual computations of what the periods of those are?


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## Brian G Turner (Aug 5, 2021)

Brian G Turner said:


> However, it's not all good news - Promixa was found to emit deadly bursts of X-Rays during solar flares during its solar cycle.



So far it's looked grim and dangerous to be on a planet orbiting a red dwarf. 

However, new research suggests that these deadly flares actually go out pole-ward from these stars, rather than from the equator - which means planets might not get much impact from them at all:









						Superflares are less harmful to exoplanets than previously thought
					

Superflares, extreme radiation bursts from stars, have been suspected of causing lasting damage to the atmospheres and thus habitability of exoplanets. A newly published study found evidence that they only pose a limited danger to planetary systems, since the radiation bursts do not explode in...




					phys.org


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## RJM Corbet (Aug 5, 2021)

I think life is what animates the form. Life doesn't have to be limited to the carbon based life forms we are looking for.

Our research is based on our spacial/temporal limitation -- our truly wonderful scientific instruments, and microscopes and telescopes, are really just extensions of our five natural/temporal senses of sight and hearing, and so on.

Life and the forms it occupies doesn't have to be limited to purely human concepts of how life can be measured in human terms. All human knowledge breaks down at the the time/space frontier. We don't know all that much, really?


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## Fiberglass Cyborg (Aug 5, 2021)

I like to think of astrobiologists living on a world orbiting a neutron star. They look out into the cosmos and lament: "Most of the stars in the sky are not neutron stars and will never attain neutron-stardom. Any planets orbiting those failed stars will forever be denied the life-giving flood of gamma rays and X-rays our benificent Sun omits. Circling forever in the feeble glow of sub-violet radiation, those bleak worlds shall remain permenantly sterile."


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## AllanR (Aug 5, 2021)

Fiberglass Cyborg said:


> I like to think of astrobiologists living on a world orbiting a neutron star. They look out into the cosmos and lament: "Most of the stars in the sky are not neutron stars and will never attain neutron-stardom. Any planets orbiting those failed stars will forever be denied the life-giving flood of gamma rays and X-rays our benificent Sun omits. Circling forever in the feeble glow of sub-violet radiation, those bleak worlds shall remain permenantly sterile."


They'll be surprised when humans show up with a ship larger than their largest city, yet with less mass than their smallest appendage.


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## Fiberglass Cyborg (Aug 5, 2021)

AllanR said:


> They'll be surprised when humans show up with a ship larger than their largest city, yet with less mass than their smallest appendage.


"We brought one of the aliens down to the stellar surface for a diplomatic reception. On arrival, the creature laminated itself over the entire surface of the Capitol District to a depth of one micron, and has not made any further communications. We do not know if this behaviour is typical of their species."


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## BAYLOR (Aug 9, 2021)

The planet orbiting Proxima B is tidal locked , with  one side pernambuco permanently facing the that sun  ,  That type of star though long lived , periodically  scotches  the surface of that planet with lethal solar flares.


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## Vertigo (Aug 9, 2021)

BAYLOR said:


> The planet orbiting Proxima B is tidal locked , with  one side pernambuco permanently facing the that sun  ,  That type of star though long lived , periodically  scotches  the surface of that planet with lethal solar flares.


Allow me to direct you to @Brian G Turner's post just 5 post prior to yours


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## BAYLOR (Aug 9, 2021)

Vertigo said:


> Allow me to direct you to @Brian G Turner's post just 5 post prior to yours



Vertigo , believe it or not, I neither read nor even saw Brians  comment.  Id heard about this for  documentary which talked about the Proxima  system.  

But ,  I should have done more reading the thread comments  before I posted.


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