Will we make contact with an extra-terrestrial life-form before life ends on earth?

[Elixir]

There could be billions of galactic civilizations in the universe, but unless one of the infected galaxies happened to be ours (still a verrrry long shot even assuming billions of galactic civilizations) we will never know about them.

 

[Angra Mainyu]

That would depend on a number of factors, such as how they communicate. But for example, it might be that after they sent radio signals when they’re planet-bound, the aliens in question stops communicating in such an indiscriminate manner.

I'm not even figuring deliberate communications efforts. ETs can see Earth from nearby stars, we should be able to see them.

A couple of points:

a. In that part of my post, I was talking about communicating between them in such an indiscriminate manner (i.e.. in a manner that sends signals in all directions like we do).

b. As I mentioned, that is not my area of expertise, but from what I read, even if the aliens use radio to the extent we do, it seems unlikely that we would be able to find them with present-day equipment.

http://www.seti.org/faq#obs12

It seems that they would need an intentional transmission, or something like high-powered radars, which an alien civilization might or might not be using - or we might not be pointing the SETI equipment at them.

Even if they were using something like those radars, and even if SETI is looking in their direction, case, the transmission would only be detected within tens or at best hundreds of light years, so a civilization beyond that distance would not be detected (save for much stronger transmissions).

I do agree we wouldn't learn a lot unless we learned to decode what we were hearing.

But that looks extremely difficult.

We can't even tell much of what dolphins are trying to communicate, even if dolphin communication might be much simpler than alien communication, and even though we have a zillion signals to study - not to mention the dolphins themselves.

Even when human languages, decyphering old languages is very difficult if information is sketchy. How would you go about deciphering an alien signal?

Safety? From what? Unless there's something like the Berserkers out there there's no reason to hide.

Safety from potentially hostile alien civilizations.

Note the implications--if we detect one that means they're very common. Yet where are the starfaring ones??

Yes, if we detected a non-deliberate attempt to communicate with us with present-day technology, such signals would probably be pretty common. But that does not entail that it's probable that we will detect such signals if there are stargaring civilizations, which might or might not be using radio signals like that - and even if some of them are, for the aforementioned reasons.

 

[Angra Mainyu]

Just an addition because the point may not have been clear:

Yes, if we detected a non-deliberate attempt to communicate with us with present-day technology, such signals would probably be pretty common. But that does not entail that it's probable that we will detect such signals if there are stargaring civilizations, which might or might not be using radio signals like that - and even if some of them are, for the aforementioned reasons.

Let's say that we managed to detect one such signal with our primitive equipment. That would be evidence that such signals are pretty common, but it would remain the case that we hardly ever find them.
As far as I can tell, the signal might or might not come from a starfaring civilization, and there might or might not be a good number of starfaring civilizations out there.

 

[Angra Mainyu]

Well, it might turn out that interstellar travel isn't as easy as it looks...

Good point (not that it looks so easy, but I think I get your point ).

While I admit I don't know much about the matter, difficulty of interstellar travel (among a couple of other possibilities) seems more plausible to me than the hypothesis Loren is proposing (in case we detected a signal), namely that civilizations like us arise very frequently but all of them ended up causing their own demise soon after reaching that level, or will soon do so (i.e., some of its members did or will do that).

That suggestion seems to impose really weird conditions on the psychology of any aliens that make it to our level of development.

 

[Loren Pechtel]

Well, it might turn out that interstellar travel isn't as easy as it looks...

It's not easy. That doesn't mean it's impossible for a society that has occupied it's star system.

Lightsails will give you 1% of c. That's enough for slowboats. We've already flown small lightsails, they work.

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There could be billions of galactic civilizations in the universe, but unless one of the infected galaxies happened to be ours (still a verrrry long shot even assuming billions of galactic civilizations) we will never know about them.

Note that billions of civilizations in the universe translates to something like a 1 in a trillion chance of a planet developing such a civilization.

Given that what are the odds of another planetary civilization being within radio range of Earth, especially given the very narrow window between the development of radio and breaking out into the galaxy?

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b. As I mentioned, that is not my area of expertise, but from what I read, even if the aliens use radio to the extent we do, it seems unlikely that we would be able to find them with present-day equipment.

http://www.seti.org/faq#obs12

I'm not saying they would receive our transmissions. I'm saying they would note the excess of radio energy being emitted.

Even when human languages, decyphering old languages is very difficult if information is sketchy. How would you go about deciphering an alien signal?

If it's intentional it shouldn't be too hard. If it's not you need to get lucky and find a Rosetta Stone--say, a chemistry textbook. (They have the same elements we do.)

Safety from potentially hostile alien civilizations.

But what reason do they have to be hostile? Interstellar invasion isn't worth it.

 

[Bomb#20]

It's not easy. That doesn't mean it's impossible for a society that has occupied it's star system.

Lightsails will give you 1% of c. That's enough for slowboats. We've already flown small lightsails, they work.
...
Given that what are the odds of another planetary civilization being within radio range of Earth, especially given the very narrow window between the development of radio and breaking out into the galaxy?

I'm neither suggesting it's impossible nor claiming it looks easy. I'm pointing out that the logic of your argument relies on your opinion that there's a very narrow window between the development of radio and breaking out into the galaxy. And that opinion is based on a judgment of how hard it is to transplant a civilization to a neighboring solar system, which in turn is based on judging what it would take to overcome the obstacles you can see in getting from one star to the next, using lightsails or similarly plausible technologies. Consequently, in the event that you are mistaken about what it would take to overcome one you can see, or there turn out to be any serious obstacles you haven't thought of, then your argument breaks down and we have to consider the possibility that single-solar-system civilizations could remain confined, but radio-capable, for hundreds of millions of years.

But what reason do they have to be hostile? Interstellar invasion isn't worth it.

That's a value judgment. Are you proposing the existence of objective value? Are you making a claim about the range of possible minds natural selection is able to produce?

 

[Angra Mainyu]

I'm not saying they would receive our transmissions. I'm saying they would note the excess of radio energy being emitted.

Radio energy?
Could you clarify that, please? What kind of transmissions would you expect that someone would find, and who would be the finder?
What I'm saying is that at least according to the SETI website, if there were a civilization like ours at a short distance, nearly all of their transmission would not be detected.
Only deliberate communication attempts, and a few radars might be detected, but that's only up to tens or maybe hundreds of light years, and if SETI happened to look right in their direction when the signal is coming.

If the aliens happen to be farther away than that, or if they are neither trying to communicate nor using that sort of radar (or similar device), or if SETI happens not to look in their direction, they would remain unnoticed.

In other words, what I'm suggesting is that the lack of our finding signals may well be because we're still not looking with sufficiently powerful equipment.

If it's intentional it shouldn't be too hard. If it's not you need to get lucky and find a Rosetta Stone--say, a chemistry textbook. (They have the same elements we do.)

But the issue is in case it's not intentional. They have the same elements as we do, but so did ancient Egyptians – who also had the same sort of minds we do; alien minds may well be quite alien.

But what reason do they have to be hostile?

I admit I do not know what reasons aliens have, because I do not know about their psychological makeup. But the point I'm trying to make is that widely variable sorts of minds seem to be compatible with the development of advanced technology – a point I see Bomb#20 has made, and more clearly.

I can suggest some potential reasons depending on psychological make up, but there are plenty of potential reasons that might be too alien for me to even guess. But for example, reasons for hostility might be:

1. Hunting for sport.
2. Eliminating potential future competition for resources, if they want to survive for as long as possible in the finite part of the universe they will ever have access to, and they can pull it off or they value that option so much that they’re willing to take the risk.
3. Just killing aliens, in case of a Xenophobic species.
4. Building an empire, if they like to dominate other intelligent species.
5. Maybe some members of a civilization made other, more intelligent beings – like a strong AI – to try to use them to control their world, and things got out of hand. Now, the engineered beings are would like to implement some sort of conquering plan, extending it as much as they can.
6. A long etc.

And even those reasons are mostly kind of human-like. Some aliens may well be way more alien.

Interstellar invasion isn't worth it.

As Bomb#20 pointed out, that's a value claim.
Whether it's worth to them depends on what they value, which may be very different from what humans tend to value (though some humans might even go for some of the reasons I gave above).

 

[General Mung Beans]

I'm optimistic that will be the case.

 

[GenesisNemesis]

I'm not sure what grounds people have for believing that we will make contact. Seems way too optimistic.

 

[Musing Man]

I'm not sure what grounds people have for believing that we will make contact. Seems way too optimistic.

Well, if space-faring intelligent life forms are numerous and happen to coexist within one given galaxy, contact is bound to happen. Even if it's not physical contact, necessarily. Moreover, even if a civilization dies out and leaves behind it some sort of a beacon, detecting that beacon would still account as a contact - it would provide a definitive answer to that pesky question, 'are we alone?'

We're somewhat space-worthy for only 50 years or so; that's historical peanuts and we can't really say that we're a space-faring species just yet. But if some other life is out there, intelligent or not, we'll find it within the next couple of hundred years, tops, despite our (still) primitive technology.

 

[Loren Pechtel]

I'm neither suggesting it's impossible nor claiming it looks easy. I'm pointing out that the logic of your argument relies on your opinion that there's a very narrow window between the development of radio and breaking out into the galaxy. And that opinion is based on a judgment of how hard it is to transplant a civilization to a neighboring solar system, which in turn is based on judging what it would take to overcome the obstacles you can see in getting from one star to the next, using lightsails or similarly plausible technologies. Consequently, in the event that you are mistaken about what it would take to overcome one you can see, or there turn out to be any serious obstacles you haven't thought of, then your argument breaks down and we have to consider the possibility that single-solar-system civilizations could remain confined, but radio-capable, for hundreds of millions of years.

Suppose it takes us 10,000 years to start launching the slowboats. That's still an eyeblink on the time scales we are talking about. The window is *VERY* narrow.

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Radio energy?
Could you clarify that, please? What kind of transmissions would you expect that someone would find, and who would be the finder?

I'm saying the total radio energy emitted. It would take a *MUCH* more careful look to figure out the excess radio energy was a civilization but detecting the fact that there was excess energy from a star that had no reason to emit it wouldn't be that hard.

 

[Bomb#20]

Suppose it takes us 10,000 years to start launching the slowboats. That's still an eyeblink on the time scales we are talking about. The window is *VERY* narrow.

I.e., interstellar travel looks so easy that it shouldn't take more than 10,000 years for a civilization to get from radio transmitters to starships. That's true. But we aren't really experts on the subject. It might turn out it isn't as easy as it looks.

Here are three obstacles off the top of my head that might turn out not to be surmountable within ten thousand years, or even ten million.

1. Radiation. Granting that lightsails can get us to 0.01c, that's 400 years to Alpha Centauri -- a lethal radiation dose many times over. The slowboat will have to be shielded. Shielding is heavy. Lightsails that can accelerate a small starship to 0.01c can't do the same to a big heavy one. We might have to settle for a slower slowboat. That's more generations in space -- which means more games of genetic Russian Roulette. We'd have to compensate with more shielding. And repeat...

2. Politics. A slowboat is an expensive project. It takes government funding. Maybe no political party can ever convince the self-interested public to take a long enough view to invest in a project that won't yield a return on investment for 400 years. Or even a progress report.

3. Ethics. As Steven Pinker points out, violence has been steadily declining for thousands of years. The "better angels of our nature" are winning. We're becoming nicer and nicer people. What if, by the time we've reached the technological stage of being able to launch slowboats, there's nobody with any influence left in our species who's still willing to sentence generation after generation of innocent unborn children to life imprisonment in a slowboat?

 

[Bomb#20]

Yes. If we are planet-bound and find another planet-bound civilization that means it's virtually certain that we will soon destroy ourselves. If planet-bound civilizations are common enough that we can find them without finding any starfaring civilizations then that means it's virtually certain that planet-bound civilizations don't become starfaring civilizations. About the only way that could happen is if they destroy themselves or effectively so do. (Say, for example, a civilization that turns to a perpetual life playing in VR.)

But what reason do they have to be hostile? Interstellar invasion isn't worth it.

This is another thing that puzzles me about your argument. If about the only way planet-bound civilizations don't become starfaring civilizations is if they destroy themselves, that must mean that starfaring is worth it. Maybe interstellar travel isn't worth it for the same reason interstellar invasion isn't. What reason do the aliens have to leave their own solar system? Specifically, what is so different about emigration and invasion? What is a reason for emigrating that's simultaneously so strong it's worthwhile to cross many lightyears to accomplish it, and so weak that it just goes away if there's somebody at the destination who doesn't want you to come?

 

[Musing Man]

I.e., interstellar travel looks so easy that it shouldn't take more than 10,000 years for a civilization to get from radio transmitters to starships. That's true. But we aren't really experts on the subject. It might turn out it isn't as easy as it looks.

Here are three obstacles off the top of my head that might turn out not to be surmountable within ten thousand years, or even ten million.

1. Radiation. Granting that lightsails can get us to 0.01c, that's 400 years to Alpha Centauri -- a lethal radiation dose many times over. The slowboat will have to be shielded. Shielding is heavy. Lightsails that can accelerate a small starship to 0.01c can't do the same to a big heavy one. We might have to settle for a slower slowboat. That's more generations in space -- which means more games of genetic Russian Roulette. We'd have to compensate with more shielding. And repeat...

2. Politics. A slowboat is an expensive project. It takes government funding. Maybe no political party can ever convince the self-interested public to take a long enough view to invest in a project that won't yield a return on investment for 400 years. Or even a progress report.

3. Ethics. As Steven Pinker points out, violence has been steadily declining for thousands of years. The "better angels of our nature" are winning. We're becoming nicer and nicer people. What if, by the time we've reached the technological stage of being able to launch slowboats, there's nobody with any influence left in our species who's still willing to sentence generation after generation of innocent unborn children to life imprisonment in a slowboat?

Any argument/obstacle against human colonization of space can be easily refuted/eliminated with much less (or much more, depending on the perspective) imaginative solutions.

Radiation? Yeah, it's a bitch now, but for how long? We can genetically engineer ourselves (well, not just now, but soon) to withstand and even thrive against anything the Universe can throw at us, minus total annihilation. That, and many more interesting alterations to Hss genome are readily possible (immortality being just one such alteration - buh-bye generational ships; dude, where's my slowboat?!). But it's dependent on Factor X.

Politics? I'm afraid that politics - and by that I mean our current perception of 'politics' (everything is politics, they say) - won't be with us for much longer. There's an upcoming revolution, very-very near. Clinton (ironically, I'd say), Gates (Bill), Buffett, Soros and many others are unknowingly (I suppose) leading it. Forget their front initiatives and mission statements (commendable in their own right), THIS is one of the end results. In brief, humans are about to replace 'The System' (bureaucracy, cronyism etc.) with an entirely different social structure system, which can be glimpsed even today. That was the good news. The bad news is that we're heading - not far from rushing - towards a hive-like society. An ”everything for the greater good” kind, the only one that ascribes value to individual contributions benefiting the collective. It may sound like communism, but it's far from that and it coincidentally resembles the most successful natural model of all times: the hive. But I'm digressing. Politics are entirely dependent on Factor X.
Ethics? Now that's a double-edged sword, if there ever was one. Ethics are an ever-changing compass, and within an ego-driven society it barely ever matters. Even in a hive-like society ethics can inflict more harm than good, irrespective of its premises. Ethics can provide at worst death, ambiguity and sorrow, and at best clarity and feel-good sentiments. Ethics also depend on Factor X.

Now, I can almost hear the question, 'what the fuck is this Factor X?' It's CONTEXT. The most important factor ever, for everything.

In this context we need to do that. In another context we might choose to do otherwise, irrespective of how refined are the ethics.
I'm sure you got the drift.

The funny thing with contexts is that they include each and every factor that simply are possible in a (or any) given situation.

Neil deGrasse Tyson pointed that there were/are only three basic motivators at the roots of human expansion: military (supremacy), economical (supremacy) and religious (supremacy).
Can anyone spot a pattern in that?
What Tyson failed to acknowledge was the most basic drive of them all: survival.

The same goes for many people. But when it comes for survival, nothing stands in the way. NOTHING. Can you argue with that?

 

[Loren Pechtel]

I.e., interstellar travel looks so easy that it shouldn't take more than 10,000 years for a civilization to get from radio transmitters to starships. That's true. But we aren't really experts on the subject. It might turn out it isn't as easy as it looks.

Here are three obstacles off the top of my head that might turn out not to be surmountable within ten thousand years, or even ten million.

1. Radiation. Granting that lightsails can get us to 0.01c, that's 400 years to Alpha Centauri -- a lethal radiation dose many times over. The slowboat will have to be shielded. Shielding is heavy. Lightsails that can accelerate a small starship to 0.01c can't do the same to a big heavy one. We might have to settle for a slower slowboat. That's more generations in space -- which means more games of genetic Russian Roulette. We'd have to compensate with more shielding. And repeat...

6' of earth or it's equivalent is virtually total protection against radiation. You can get this from the cargo you are carrying. I'll also add that radiation roulette isn't nearly as dangerous as you seem to think it is--people living in high radiation environments on Earth aren't dropping like flies. Acute exposure is clearly dangerous and seems to yield about 1 tumor per 50 Sieverts. Chronic low-level exposure, though, is another matter--nobody has managed to show any actual risk. (All the estimates of risk come from figuring the same 50 Sieverts/tumor number applies.)

2. Politics. A slowboat is an expensive project. It takes government funding. Maybe no political party can ever convince the self-interested public to take a long enough view to invest in a project that won't yield a return on investment for 400 years. Or even a progress report.

You're missing the fact that I'm not relying on government to do it. Rather, I'm figuring the effort will come from groups that choose to leave. That's where colonization efforts usually come from. If nothing changes to make it easier I expect to see private groups do it when the cost drops to the point that they can.

3. Ethics. As Steven Pinker points out, violence has been steadily declining for thousands of years. The "better angels of our nature" are winning. We're becoming nicer and nicer people. What if, by the time we've reached the technological stage of being able to launch slowboats, there's nobody with any influence left in our species who's still willing to sentence generation after generation of innocent unborn children to life imprisonment in a slowboat?

It's not that different than a space habitat.

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This is another thing that puzzles me about your argument. If about the only way planet-bound civilizations don't become starfaring civilizations is if they destroy themselves, that must mean that starfaring is worth it. Maybe interstellar travel isn't worth it for the same reason interstellar invasion isn't. What reason do the aliens have to leave their own solar system? Specifically, what is so different about emigration and invasion? What is a reason for emigrating that's simultaneously so strong it's worthwhile to cross many lightyears to accomplish it, and so weak that it just goes away if there's somebody at the destination who doesn't want you to come?

Because the somebody at the destination can stop you. It's much harder to establish yourself against opposition than it is to get there in the first place. Given even remotely similar tech levels the defenders will have an easy time of it.

 

[Bomb#20]

Any argument/obstacle against human colonization of space can be easily refuted/eliminated with much less (or much more, depending on the perspective) imaginative solutions.

But that wasn't an argument against human colonization of space -- I'm in favor of human colonization of space and I think it will happen. It was just an argument against it being inevitable if we don't destroy ourselves first. You're right that context might well overcome all the obstacles I pointed out. Or it might not. That's the thing about context -- we don't know what it's going to be so we don't know which direction it's going to push us in.

Radiation? Yeah, it's a bitch now, but for how long? We can genetically engineer ourselves (well, not just now, but soon) to withstand and even thrive against anything the Universe can throw at us, minus total annihilation.

Maybe we can. Maybe not. It might be harder than it looks. All the really rad-hard organisms are tiny. We're kind of new at all this; let's not kid ourselves that we know more than we actually know.

In brief, humans are about to replace 'The System' (bureaucracy, cronyism etc.) with an entirely different social structure system, which can be glimpsed even today. That was the good news. The bad news is that we're heading - not far from rushing - towards a hive-like society. An ”everything for the greater good” kind, the only one that ascribes value to individual contributions benefiting the collective. It may sound like communism, but it's far from that and it coincidentally resembles the most successful natural model of all times: the hive.

Really. Eusociality is so successful it's evolved over and over again. Specifically, since the Cambrian explosion it's evolved independently at least eleven times in the wasp family; and, in the entire rest of the animal kingdom, once. It's a successful model for wasps because they're haplodiploid. The mathematics of their reproduction makes a female's genes propagate more if she helps her sister breed than if she breeds herself, which makes a hive work well for them. That's not the case in humans, so a hive is unlikely to be an evolutionarily stable strategy for our genes.

What Tyson failed to acknowledge was the most basic drive of them all: survival.

The same goes for many people. But when it comes for survival, nothing stands in the way. NOTHING. Can you argue with that?

And that may well be the answer to my question to Loren: what's a good enough reason to cross the stars for, but not a good enough reason to make war for?

If the reason a galactic civilization isn't already here is that interstellar travel is harder than it looks, then that means making radio contact with aliens wouldn't be Loren's ominous warning that we're about to destroy ourselves. But it would still be bad news: an ominous warning that we'll never become a galactic civilization ourselves and are doomed to confinement to our own solar system, and extinction when the sun boils the oceans away or the next Siberian Traps open up. Unless...

Unless the reason a galactic civilization isn't already here is that the only reason good enough to cross the stars for is exactly what you say: survival -- the need to not have all your species' eggs in one basket, at constant risk of extinction from a local disaster. For that reason, any alien species that achieves radio communication and interplanetary travel needs to up its game to starships. But they don't need to do it very many times. Once you spread to half a dozen star systems you should be safe from extinction. Get a new star every few billion years when an old one becomes uninhabitable. Colonize a few red dwarf systems that will be stable for a trillion years. Why expand any further than that? And if you ever encounter other starfarers, no incentive to invade their systems when you can just migrate in a different direction.

So if we do make radio contact with aliens, maybe what it means is that the galaxy is split up into a million little dozen-star territories, with a hundred lightyears of uncolonized wilderness between neighbors, and we're on the verge of earning ours.

 

[Musing Man]

Well, good man, a tough question arises: if a galactic civilization was to be here - for observing or any purposes other than contact -, could we really tell? Assuming a spaceship, shiny mylar tights and ray guns won't help. Same goes for radio communication.

We suck at identifying our very own real drives/motivators, so I wouldn't hold my breath waiting for a human to figure out what kind of push was behind a hypothetical ET (way more advanced than us by definition) that cannot even be recognized as such.

Oh, and about the hive society: we're closer to it than most people would like to imagine we are, albeit in a peculiarly warped way. It's a structure that comes rather naturally in reasonably old and very large populations. One central command and a huge army of more-or-less- zombies. Have a look around.

 

[Angra Mainyu]

Here are three obstacles off the top of my head that might turn out not to be surmountable within ten thousand years, or even ten million.

1. Radiation. Granting that lightsails can get us to 0.01c, that's 400 years to Alpha Centauri -- a lethal radiation dose many times over. The slowboat will have to be shielded. Shielding is heavy. Lightsails that can accelerate a small starship to 0.01c can't do the same to a big heavy one. We might have to settle for a slower slowboat. That's more generations in space -- which means more games of genetic Russian Roulette. We'd have to compensate with more shielding. And repeat...

2. Politics. A slowboat is an expensive project. It takes government funding. Maybe no political party can ever convince the self-interested public to take a long enough view to invest in a project that won't yield a return on investment for 400 years. Or even a progress report.

3. Ethics. As Steven Pinker points out, violence has been steadily declining for thousands of years. The "better angels of our nature" are winning. We're becoming nicer and nicer people. What if, by the time we've reached the technological stage of being able to launch slowboats, there's nobody with any influence left in our species who's still willing to sentence generation after generation of innocent unborn children to life imprisonment in a slowboat?

Tough problems!

I’ve been thinking of ways to overcome them in 10 million years (just to test potential alternatives and difficulties, because it's fun ), and they look really tough to me.

I have a couple of ideas mostly for 1, but they’re very tentative, and they do not guarantee success even for the shielding problem, so I agree that those obstacles might turn out not to be resolvable within that framework.
Anyway, these are the alternatives I have in mind:

Alternative A:

a. Colonize the Solar System.
b. Develop robots capable of raising healthy human children. That involves any required computer programs, video and audio of real humans if needed, human-looking bots, and so on.
c. Test the robots exhaustively – if needed, for thousands or tens of thousands of years -, both on Earth and elsewhere, at first aiding real humans, and then – only when it’s absolutely clear it’s safe – without them, though with humans within range in a couple of minutes just in case, and until one gets it right (well, not one, but a series of different people over a long time, which plausibly further strengthens 2., at least as long as age can’t be conquered).

Points a., b., and c. can be achieved within 1 million years in my view (a conservative estimate I think), though I might be missing something.

d. Develop artificial wombs, whether perhaps partly biological – but with no brain, except for the relevant parts.
This one might be the limiting factor. Still, even a brain-dead body can continue a pregnancy, so why not an artificial womb, plus any necessary auditive input from robots?
There is, however, another difficulty. If it needs to be partly biological, then how can one send it to the destination?
But perhaps this is easier than in the case of humans, if it can be frozen (for example).
Alternatively, it might still be made so that it grows without the need of another partly biological support, in some sort of egg, assuming the egg can last for longer frozen.
Or maybe it doesn’t need to be partly biological. In any case, this looks like the most significant hurdle in overcoming 1 with this approach.
On the other hand, if d. is achievable, then I'd say a-d are probably achievable all within 1 million years.

e. Pick a planet with a surface gravity from 0.8g to 1g and not too hot within 100 light years, and colonize it with robots only, building infrastructure for humans over there. Alternatively, pick a planetary system within 20 light years and colonize it with robots only, making large ships with rotating parts.

At least one of the two possibilities in e. seems doable within 5 million years, so let’s say 6 million in total.

f. Send 10 slowboats without life support or massive shielding in most of it, but with a heavily shielded room transporting zillions of frozen embryos and/or eggs and sperm cells.

I think f. avoids the shielding problem, since a ship mostly without life support and with only one heavily shielded room would not be so difficult, given how much room can be saved by not having to sustain living people.

However, if even that is very difficult, the ships carry zillions of those embryos each, and only a few have to make it, since the robots are going to test them before they start, or at the beginning of the development, destroying any with problems before a brain develops.

g. Have the robots make people on the other side.

The whole process would take less than 7 million years (a conservative estimate I think), if it’s achievable at all. The main difficulty may be d., in which case this variant fails.

If d. is doable, then this option would seem to avoid the problem of shielding. There is of course 2., and while 3. is also avoided, there is also the ethical issue of children whose only human interaction is with other children, so an alternative ethical problem seems to arise.

Alternative B:

a. Develop a way to remove C14 and more importantly K40 from human or GM human bodies. The C14 shouldn’t be that difficult given (say) a million years, if not for other reason just because they can probably grow food in a controlled environment without input of C14, and the C14 inside decays. K40 can’t be handled in that manner sufficiently quickly, but there already is a proposal for testing the effects very low levels of radiation on non-human animals using an “Ultra-Low-Level Radiation laboratory”, ( https://en.wikipedia.org/wiki/Radiation_hormesis#Effects_of_no_radiation ), so given much more advanced technology, a sufficient reduction seems doable.

b. Develop genetic engineering and/or other technologies to freeze GM humans. This may not be doable, though, so it's this alternative might be blocked.

c. Colonize the Solar System, test ships and all of that in the Solar System, and then colonize the target location with robots.

d. Send the humans in a heavily shielded ship. I think even heavy shielding will be doable if there is no need for all of the systems required to sustain a living community.
So, it seems to me that the limiting factor is b. and perhaps a. If they’re both doable, all of the steps would be achievable in less than 5 million years (seriously conservative estimate I think). This would resolve problems 1. and 3., though 2. remains.
There is another difficulty, though. If it turns out that extremely low levels of radiation (much less than normal) actually is a health hazard, and unless genetic engineering or something else can overcome that, people with almost no K40 and C14 would be less healthy on average, which brings back ethical problems if they're raised that way.

Alternative C:

a. Make GM humans who are more resistant to radiation.
b. Make GM humans who don’t get old.

Okay, that is a stretch. It would resolve 1. and 3., though. But then, a new problem arises – which is an obstacle on its own, it seems to me, in case b. is actually doable: When people no longer get old and nearly all illnesses can be either prevented or cured or both, who’s going to volunteer?

Alternative D:

Given infrastructure on both sides (i.e., colonization of the Solar System by humans and the target planetary system by robots), how fast can one toss and catch a moon? (it depends on the size, but given a few million years, I'm guessing it's doable with any moon the size deemed adequate).

Catching it would not seem to be required, though. With considerably faster ships waiting on the other side, people could just get off their moon if needed.

The facilities deep underground the moon would be shielded by lots of rock, so that would resolve 1., despite the fact that the boat would be awfully slow.

Also, the place might be big enough to resolve 3, at least when it comes to confinement. Then again, there is the problem of low gravity (among others), so it seems to me that 3. remains, even if attenuated. Even with GM humans, it would probably be tough.

In any case, point 2. is not address.
​

All alternatives are very tentative, or slow (and they don’t address all of the problems, anyway). So, as I mentioned my assessment is also that those problems might turn out not to be surmountable within 10 million years.

 

[Angra Mainyu]

You're missing the fact that I'm not relying on government to do it. Rather, I'm figuring the effort will come from groups that choose to leave. That's where colonization efforts usually come from. If nothing changes to make it easier I expect to see private groups do it when the cost drops to the point that they can.

And you expect that their motivation will last for generations?
Also, will they even be allowed to do that to children?

It's not that different than a space habitat.

But they would be placing children there for their entire lives, with no possibility of escape. In addition to the moral issue, there is a legal issue. Will they be allowed to do that? And if they aren't, will they be able to break the law and get away with it?

 

[Unbeatable]

The same goes for many people. But when it comes for survival, nothing stands in the way. NOTHING. Can you argue with that?

Short-sightedness often stands in the way of making decisions necessary for long-term survival.