communicating with an extraterrestrial civilisation

[halogirl]

to: darklance

thats why i said universe. and yes, TheDarkShade, it would be.

[noz92]

I would find it probable that any compassionate alien race (as any capable of interstellar travel and communication must be--otherwise they would probably wipe themselves out when they reached a certain level of technological development) would follow something similar to "the Prime Directive" in Star Trek--that is, every race has its right to its own technological and social development, and as such, members of Starfleet are prohibited from interfering with the development of any primitive culture, even at the cost of his life. Seeing as how meeting an alien would be an enormous culture shock to humanity, most aliens probably wouldn't make contact with us until we were ready.

 

On our method of searching for extraterrestrials--SETI's most common method (listening for radio signals) seems as though it wouldn't work. I assume (I don't have any evidence for this, other than analogy) that, for the same reason that a sound becomes less and less detectable the farther away from its source you are, it would seem as though radio would work in much the same way--if you get far enough away, no one would be able to read your radio signals, or, for that matter, even hear them as something other than cosmic noise, which it would blend in so well with.

[Edtharan]

I would find it probable that any compassionate alien race (as any capable of interstellar travel and communication must be--otherwise they would probably wipe themselves out when they reached a certain level of technological development) would follow something similar to "the Prime Directive" in Star Trek--that is, every race has its right to its own technological and social development, and as such, members of Starfleet are prohibited from interfering with the development of any primitive culture, even at the cost of his life. Seeing as how meeting an alien would be an enormous culture shock to humanity, most aliens probably wouldn't make contact with us until we were ready.

I remember hearing a scenario where by an Alien race (more advanced than ours) descides to supress any other race advancing too far because they might not be as compasionate as themsleves. They could come to this conclusion from the fact that they would have needed to have some form of agression (but now have advanced past it) to survive and become the dominent specices on their world.

 

But, because they can't be certain that another species might develop a greater technology than them, and still be as compasionate, then they would feel that they have to supress the development (or even wipe out a species that is getting too advanced and showing signs of agression still) of other developing races.

 

This would be the opposite of the "Prime Directive" approach, in that these aliens would have to activly suppress these other races (which might include annhialation).

[noz92]

That would seem unnecessary. I think that any advanced race must widely develop pacifism in order to survive--if they do not, by the time they reach a certain level of advancement, naturally they would develop weapons that would endanger themselves, and it only takes a small group to use these weapons. As such, natural selection probably only allows compassionate species to become advanced to a certain level. If I'm right, the aliens would probably recognize this and give us a chance to wipe ourselves out.

[SkepticLance]

To noz

 

One problem with your hypothesis is the time factor.

 

About 10% of the star systems in our galaxy are up to 2 billion years older than our own. If intelligent species and civilisations are 'common', then a number will be up to 2 billion years older than our own.

 

If they developed at the rate our own species seems to be developing, they would have arrived at Earth sometime between one and two billion years ago. They would have been greeted by a planet inhabited by slime. I think a 'prime directive' directed at slime would be a bit of a stretch of the imagination. There would seem to me to be no ethical constraint stopping them colonising a planet of slime.

[noz92]

Perhaps they never found Earth, they never saw a use for it, or they had ethical objections for disturbing something that may eventually develop into a sapient species. It's probable that, due to the impossibility of traveling faster than light, the idea of colonizing worlds more than a few light years away would seem impractical. They may have also saw the possibility of life on Mars, for example, discovering them someday (if there was life on Mars, which is entirely possible, though perhaps never sapient), and therefore found colonizing a world so close to Mars a possible violation of the "Prime Directive". Perhaps they did, and the idea of panspermia would be possible; or maybe the did establish colonies on Earth until, for some reason, they were forced to leave. Given only a few thousand years, nature could completely wipe away any evidence of civilization.

[SkepticLance]

To noz.

 

I hope you forgive me for this, but I cannot agree with your arguments.

 

For a start, any species that has interstellar space travel, as humans will have within a thousand years or less, will be able to colonise every system in the galaxy. The one thing that makes astronomical numbers look small is the potential for population increase, given space to expand into. Just do the numbers.

 

Given the ability to travel at (say) 0.1 c, any intelligent species could cross the galaxy in 100,000 years or less. Minimal compared to the 5 to 6 billion years life may have existed in some star systems.

 

Looking at Earth life, we see various things held in common. One is adaptations for dispersal. It seems probable that evolution would have accomplished this for life outside Earth also. In any intelligent species, evolution towards better dispersal should include bahavioural dispersal adaptation. In humans this comes from our curiosity and tendency to explore outside home territory. This behaviour has led to colonisation of the entire planet, and should (if we survive) lead to colonisation of the galaxy given enough time.

 

As to nature wiping all signs of intelligence within a few thousand years - not so!

We have fossils (imprints in soft mudstone) of jellyfish 800 million years old. How long would a glass coke bottle last inside mudstone? I think it would be billions of years. Yet we have never seen a single alien artifact anywhere.

[noz92]

Even so, a species that follows the idea of a "Prime Directive" would probably pick up after itself once it realizes the possibility for more complex life to develop, as our finding an alien artifact would obviously have a very similar effect on our culture to that of actual first contact.

 

It's one thing to sit in a ship for a few months, but how many people do you know who would not only volunteer to spend the rest of his life in a space ship, but the entire lives of his children, and their children, and their children, etc., for 100 000 years? Almost everyone has some desire to explore, but most people don't once that exploration reaches a level of impracticality high enough, and I'm sure their is a limit on everybody (and I'm sure 100 000 years in a ship with the same people far exceeds that limit). It's more likely that they would expand as they need to, and exploration would be done entirely by unmanned probes. (After all, when exploration takes 100 000 years, information on a computer would become lost, pen and paper begin to decay, and facts passed down from one generation to the next quickly become legends--the most efficient means would be to immediately send the data back to civilization, and let the unmanned probe continue its journey of exploration or abandon it (with the former seeming more economic).)

[SkepticLance]

To noz

 

Continuing with my disagreement....

 

If a dead jellyfish can leave an impression in mudstone that lasts 800 million years, I think it is a bit non credible to suggest that a species that colonises (or even visits) a world can clean up enough to leave no trace.

 

On interstellar travel. Of course, no-one will travel 100,000 years. I used that number to show how small our galaxy really is - not to say that is the way it will be colonised.

 

What is more likely to happen is that large habitats - cities in space - will appear, and will become close to self sufficient, given cometary debris etc to mine. Such a city is a ready made space ship on the largest scale, even though they probably will be built initially for activities much closer to home.

 

To travel to another star, I would suggest one method might be to strap on a linear accelerator - possible 10 kilometres long - and fire charged particles at close to light speed. The city will then, according Newton's third law, accelerate in the opposite direction. To decelerate, just turn around, or fire the particles in the opposite direction. In the vacuum of space, a particle accelerator should be relatively simple to construct.

 

If we assume acceleration sufficient to reach 0.1 c in ten years, then travel to our nearest star (alpha centauri) would take 55 years, including deceleration. Each step in galactic colonisation will be similar to this, and will be done in the comfort of a city habitat of 1 million or more people.

[noz92]

While I have no doubt that life is a common occurrence in the universe, sapient, intelligent life may be much less common (after all, as far as we know, it only developed once on Earth), the distances between inhabited worlds may be much too large to cross at any acheivable speed, especially without actualy having a truly practicle and immediately beneficial reason, and so it's very probable that our existence is not known, and that is the reason we haven't been contacted (although I'm sure many species would follow a sort of "Prime Directive", and I stick with the pacafism argument).

[SkepticLance]

Actually, intelligence has evolved on several occasions on Earth, though probably not to the level of current humanity. Dolphins and whales are often very intelligent, and we have no common ancestor with them for 100 million years. This means that cetaceans evolved intelligence independently from humans. Ditto elephants. Ditto various members of the carnivora.

 

However, life on Earth is 3 to 4 billion years old, and the fossil record suggests 4 billion is much more likely. Not until 500 million years ago did organised, multi-cellular, bilaterally summetrical and mobile life evolve, even to the level of a flatworm. This means that seven eights of the history of life on Earth was very primitive.

 

Life off Earth may be like that. Mostly in the primitive state.

 

My own view is that intelligent and technologically advanced life off Earth, and still inside our galaxy, is very rare. If it had been other than very rare, we would expect at least one such species to have colonised Earth some time in the past 2 billion years, and left traces. Most of the arguments used to counter this idea depend on there being few other intelligences, because those arguments would never apply to all such intelligences.

 

eg.

They killed themselves off. OK. Some might have - but not all.

They were stay-at-home philosophers. OK. Some might be - but not all.

etc.

[noz92]

I don't think that any would venture too far away from their home planet without need to specifically do so. Traveling on the interstellar scale is far too slow to have any practical application, assuming there is absolutely no way to travel faster than the speed of light (e.g. wormholes, Alcubierre drive, etc.), as not only would the travel time be too great, but communication between colonies would be almost impossible (imagine trying to communicate with a colony around Proxima Centauri--it would be three to four years before your message is even received, and twice that before you hear a response), so they probably would not want to spread too far out.

 

For aliens to colonize Earth, they would have to be in the right place (the ideal distance) at the right time (assuming they don't want to interfere with our development) and in the right situation (i.e. the need to expand, such as overpopulation or suddenly unfavorable conditions on their home planet), and they would have to develop on a planet with similar conditions to Earth at the time (how much would an alien want Earth a billion years ago? Would it be able to support them? Would it be easily terraformed to fit their life? etc.). If these conditions are not all met, they would probably just send out unmanned probes (assuming, again, that they even have an interest in Earth) to do their exploring for them, and leave the colonization closer to home (they can't be that close to us, or we would probably have detected some trace of them, such as radio signals).

[SkepticLance]

To noz.

 

Inside a galaxy, distance is not a problem. It is just a matter of time. Lots of people, including me, have calculated how long galactic colonisation would take. All agree it would be less than 10 million years. A space vessel able to travel at 0.1 c is theoretically very possible. That is quite sufficient to colonise the entire damn Milky Way inside 10 million years.

 

My own view is that the future will include planet bound people, and people living in space habitats or cities. The latter will be those who colonise the galaxy. Easy to move a space habitat since there is no need to fight a gravity well from a planet. Such people will be genetically altered to be immune to high radiation and to harm from zero gravity. They may well live very long lives so that a journey of 50 to 100 years holds no fears.

 

An alien species that reached that stage more than 10 million years ago would already have occupied the entire galaxy. Their space cities would be very visible, and probably radiate on all sorts of frequencies. Where are they?

[D H]

Where are they?

 

Exactly. Suppose some alien civilization does develops the ability to get off its home planet in any quantities. Said species will soon colonize its own star system in short order because civilization is quite fragile. A civilization that stays on its home planet is committing suicide.

 

Life on Earth is very robust; it has even handled some incredible catastrophes (at the expense of losing 90% of all species of life extant at the time). Modern civilization is not nearly so robust. It would take much less than a dinosaur-killer meteorite to wipe out civilization. Once wiped out, its done. We have already used up a significant percent of the reserves of fuel that took hundreds of millions of years to develop and we have depleted all of the easily mineable metals. Without fuel or metal, how will our survivors (or the next intelligent species that comes along) develop past stone age capabilities?

 

Intelligence, defined as the ability to escape the planet, has one, maybe two, chances to arise in the lifetime of the planet. A truly intelligent species would not let that one-time opportunity pass them by. On most planets, I suspect the odds are essentially zero. Advanced (multicellular) life was a fluke. If such a species came across a slime ball of a planet (e.g., Earth for the vast majority of its history), it would and should colonize it. They haven't come here because they don't exist (in this galaxy).

 

There is one exception: Some intelligent species might decides to forego planetary life altogether. Such a species would be even more free to exploit the resources of the galaxy than a planet-bound species. Planets might be a bit tough to attack, but not asteroids. We live in an untamed solar system. They haven't come here either, and its because they don't exist (in this galaxy).

[thedarkshade]

Life on Earth is very robust; it has even handled some incredible catastrophes (at the expense of losing 90% of all species of life extant at the time).

Where could we find a shelter? The only one we could afford is moon, but the conditions there are much worse than here you know!

[SkepticLance]

To thedarkshade

 

As D H pointed out, the obvious shelter is space itself. Why become bound to a gravity hole? Living in space cities leaves civilisation mobile, and there are heaps of resources to tap - asteroids, mooms, Saturn's rings, - even the Oort Cloud.

[SH3RL0CK]

To thedarkshade

 

As D H pointed out, the obvious shelter is space itself. Why become bound to a gravity hole? Living in space cities leaves civilisation mobile, and there are heaps of resources to tap - asteroids, mooms, Saturn's rings, - even the Oort Cloud.

 

OK, I can see how this would work. But wouldn't the conclusion eventually end up the same? There are only so many resources in a given solar system, given enough time wouldn't these civilizations be force to leave a solar system because the resources there are exhausted or because the civilization has outgrown that particular solar system? Therefore, they would still reach us out of necessity.

 

And if e.t. was mining the moon for iron ore, I think we would notice.

 

Of course, how much time it would take to do this could be longer than the present age of the universe depending factors such as the civilization growth rate, size of the solar system, etc. I have no idea how to calculate this critical time (to consume the resources of a solar system), but since we are talking exponential growth of the civilization, I imagine the argument is still valid.

 

Or is the resources in a given solar system THAT much greater than on a single planet?

[SkepticLance]

SH3RLOCK

 

If we are talking about a few alien species, it is possible that the resources would be enough to keep them from expanding. However, if there are many such species in our galaxy, then at least one will have a rapidly expanding population that will force them to expand throughout the galaxy.

 

This is where a heap of the explanations for why we have not seen any trace of ET fall down. Each explanation may suit for one species, but not for the wide range if alien species are common.

[jeff Mitchel]

I feel we have more in common with tadpoles then we would with any alien lifeforms; and of course we don't converse with tadpoles. The search by SETA and others is unfortunately a waste of time and money. We are looking for aliens that would be in the approximate time frame that we are in. What are the chances of that? A couple of hundred years ago we would have been using smoke signals. Not that there aren't other life forms out there. From experiments on mars you either have alien life forms or you have magic dust which eat nutrients and produce gas. Interesting how no other experiments for life on mars have been forthcoming since Carl Sagan. What would that do to world religions if life were found elsewhere?

[thedarkshade]

As D H pointed out, the obvious shelter is space itself.

Sure it is, there is lots of room out there that's for sure, but the problem is with us. We are not ready yet and not able to travel to other planets and stay there like we do inside our lovely Earth!

[SkepticLance]

To Jeff

 

Mars may not be a good example. There is now plenty of evidence that certain bacterial spores are tough enough to survive months in space, and even to survive serious impacts. Thus, Earth bacteria might travel inside rocks to Mars and colonise. There is no need for life to actually arise on Mars. It might have got there from Earth. We know that some asteroid impacts on Earth, like the dinosaur killer, can kick Earth rocks into space, and beyond. If one had bacterial spores inside it, and the rock made its way to Mars, it might introduce Earth life to Mars.

 

Since we have rocks picked up in Antarctica which are identified as having come from Mars, the reverse seems very likely.

 

I predict, that if we find life on Mars, a nucleic acid sequencing analysis will show it is related to Earth bacteria.

[jeff Mitchel]

In the experiments for life on mars, the nutrients introduced were turned into gas extremely fast; much faster than any earth life form. That gave rise to the magic dust theory. Carl Sagan said in his book "Cosmos" that if an alien life form (different than life on earth) exists on mars, then we should leave mars alone. We could be opening a can of worms that makes the movie "Alien" look like a walk in the park.

[SkepticLance]

To Jeff

 

As I recall it, the results were considered to be explainable more reasonably by a purely chemical reaction, which would, of course, be much faster than simple microbial activity. There is a lot of radiant energy hitting the Martian surface, which could result in unstable and reactive chemicals forming there, ready to react with our culture media.

 

However, even if the results are due to very quickly responsive bacteria, they may still be of Earth origin. If Earth bacteria reached Mars, it may have happened a hell of a long time ago, leaving plenty of time to evolve into substantially different forms. Adaptation to the nutrient deficient Mars environment may have resulted in bugs that respond really quickly to new opportunities.

[foofighter]

A question on alien written languages:

 

To the best of my knowledge, the only way we can decipher ancient languages of humans is because we have clues from other places, like the rosetta stone, or extant languages that are similar to the ancient ones.

 

So therefore, assuming aliens had a written language, there would be no way to decipher it, even with computers. Sure you can find patterns in the writing, but what does each symbol stand for? You need to be told this - you can't figure it out. It's akin to me trying to teach someone who is illiterate how to read by writing instructions for him on how to read.

 

Am I right, or is there a loophole? Can we discover a written language's meaning from text alone?

 

I think the same argument would apply to spoken language.

 

Thus it would seem we'd have to find another way to try and communicate with aliens.

[insane_alien]

I think the same argument would apply to spoken language.

 

you learned how to speak as a baby yeah? you didn't get clues from other languages you just picked it up. this would basically be how it would work with spoken language or even written language. there are hints to what things mean and then you can build up a basic framework that will allow you to ask what words mean in the language in question and understand the description. after that it is easy.

 

for written language, we could be given clues for their number system(the symbol followed by tally marks or something).

 

i think if we are contacted by an alien civilization they will have experience at it. or at least will be smart enough to figure out something. i mean, we've figured out some of the 'language' of chimps and other primates by watching them.