Astronomers: Please stop shouting out to the universe.

[Noclevername]

Possible in the sense that Van Rijn's invisible elf is possible.

No, not really. The two areas developed independently, but are connected in our minds simply by virtue of the fact that they both have to to do with "space", which is enough of an abstract, human concept that it's entirely possible that an alien may not link those two concepts together at all, especially if their means of sensing is different than ours. Our way isn't the only way possible.

[WalrusLike]

Interstellar travell is hard. Detecting technological civilizations is comparatively easy.

In the end if you want to convince people to stop broadcasting you should give a plausible scenario where it might be harmful. Actually, it would have been nice if you did it in your opening post, but better late than never.

I made a number of mistakes here... the first was in assuming a modicum of familiarity with the topic on behalf of members. Surely you don't need a scenario spelled out.... I couldn't be bothered.

Interstellar travel might not be hard at all for a long-standing space faring species. It simply might be a matter of so many worlds... so little time.

Detecting us is not difficult (assuming a degree of interest and capability).

Again, and for the last time.... its a matter of probabilities.... the louder that you shout the more chance an aggressive species will hear you... this applies both in forests and in galaxies.

I am out of time and patience.... those who would like to continue with space opera scenarios please carry on....

[Noclevername]

I made a number of mistakes here... the first was in assuming a modicum of familiarity with the topic on behalf of members. Surely you don't need a scenario spelled out.... I couldn't be bothered.

Interstellar travel might not be hard at all for a long-standing space faring species. It simply might be a matter of so many worlds... so little time.

Detecting us is not difficult (assuming a degree of interest and capability).

Again, and for the last time.... its a matter of probabilities.... the louder that you shout the more chance an aggressive species will hear you... this applies both in forests and in galaxies.

I am out of time and patience.... those who would like to continue with space opera scenarios please carry on....

You are the one who seems to lack familiarity, like how large space actually is, and how difficult it really is to cross. You also seem to be making a lot of assumptions about an alien species' capability and actions. Interstellar travel being easy, and detecting civilizations a snap? "Wolves" prowling the dark spacelanes, ready to menace any sign of civilization? Those are definitely Space Opera concepts.

[WalrusLike]

You are the one who seems to lack familiarity, like how large space actually is, and how difficult it really is to cross. You also seem to be making a lot of assumptions about an alien species' capability and actions. Interstellar travel being easy, and detecting civilizations a snap? "Wolves" prowling the dark spacelanes, ready to menace any sign of civilization? Those are definitely Space Opera concepts.

And this is why I am out of patience...

I fully realise (as much as a human can....) how big it is... And how old it is. I know that it is unlikely for our technology to achieve interstellar travel in the next few hundred years... if ever. I have never said that detecting civilisations is a 'snap'. The 'wolves' word is an allegory. "Spacelanes'??? come on.... Finally..... The only assumption that _I_ am making is that it would be foolish to make assumptions about aliens.

I am slightly conversant with the Drake equation, SETI, the Fermi Paradox, current thinking on signal detection ranges, natural selection, extremophiles, exobiology and all the rest of the basic stuff that is behind my point. And yet I still consider myself largely ignorant on the matter....

Irrespective of all that... I would be surprised if anyone believes that any one group of astronomers has the right to do an experiment with all of earth in the potential firing line. (although now that I think about it.... some [insult deleted] here actually think they do....)

I am done here... I hope that at least one person.... (who is in a position to affect anything) might have had a seed of doubt placed in their mind by this. Maybe next time they hear folk glibly planning to speak for all of earth they might be moved to offer an alternate view.

[Noclevername]

And this is why I am out of patience...

I fully realise (as much as a human can....) how big it is... And how old it is. I know that it is unlikely for our technology to achieve interstellar travel in the next few hundred years... if ever. I have never said that detecting civilisations is a 'snap'. The 'wolves' word is an allegory. "Spacelanes'??? come on.... Finally..... The only assumption that _I_ am making is that it would be foolish to make assumptions about aliens.

I am slightly conversant with the Drake equation, SETI, the Fermi Paradox, current thinking on signal detection ranges, natural selection, extremophiles, exobiology and all the rest of the basic stuff that is behind my point. And yet I still consider myself largely ignorant on the matter....

Irrespective of all that... I would be surprised if anyone believes that any one group of astronomers has the right to do an experiment with all of earth in the potential firing line. (although now that I think about it.... some ning nongs here actually think they do....)

I am done here... I hope that at least one person.... (who is in a position to affect anything) might have had a seed of doubt placed in their mind by this. Maybe next time they hear folk glibly planning to speak for all of earth they might be moved to offer an alternate view.

Alternative views are heard all the time. But since we have no way of knowing how common life is, or how often it actually evolves into sapent life, and how often that sapient life survives long enough and has the inclination to build a technological civilization, and that we have no evidence that anything is near enough to us to be any danger, it's been judged to be not any greater a risk that anything else we do.

You aren't the first to think of these concerns; you aren't the first to present them to scientists. They've been thoroughly considered.

[Anthrage]

I think it is reasonable to be concerned about the issue at hand. Assumptions are made on both sides - and in all cases where there are unknowns, it is always best to err on the side of caution; all things being equal.

However, much of this depends upon opinion. Would it be safer to remain silent? One need not require the assumption of aliens being hostile to be true to recognize the simple logic of silence being safer, regardless. This is undeniable.

But, human beings have not progressed as they have by doing the safe thing. We cannot know what we might be passing up by being a quiet civilization. The one constant on both sides of this argument is that our presence would be detected by an advanced intelligence. For the sake of simplicity, we can reduce this to a very straightforward question, and approach this from another angle.

Let us say that through the SETI program, we detect undeniable evidence of intelligent life, in a system 1000 light years from ours. This detection is made in such a way that the nature or disposition of the civilization in question is unclear - we intercept television signals from this planet, and having watched episodes of the alien equivalents of both 7th Heaven and American Gladiators, we cannot determine if they are hostile or not.

Until this point in time, we have found no other evidence of intelligent life in the universe. We are, as far as we know, entirely alone. Having finally found someone else out there, and after years of observation, finding them to be much like us...do we contact them, or do we remain silent.

This is the choice we are faced with. We can never be assured of a lack of hostility on the part of anything we might find out there. Safety does come at a price. It may well be a decision that should be made at the highest level, and not by any single program or astronomer...but the decision remains.

For myself, I think it would be a damn shame to refuse that challenge, to reject that opportunity, to stick our heads in the sand and hope no-one notices us. It may well be that the reason we have not detected others as of yet is because this cautious attitude abounds in the universe...and if that is so, I can think of few things sadder.

God I hate to say it, but perhaps the phrase 'to boldly go' was more well thought out and more deeply considered than I'd ever imagined. It certainly seems to come down to that, when you examine what we will no doubt face, hopefully, someday.

[eburacum45]

Never mind about messages, which are single, short duration, highly directional beams; how about radar transmissions, which are more powerful and spread out in many directions? I live near a phased-array radar system which could be detected by Earth instruments thirty light years away. Are you suggesting we stop using that?
Are you in fact suggesting we stop defending ourselves?

[WalrusLike]

..how about radar transmissions...which could be detected by Earth instruments thirty light years away. Are you suggesting we stop using that?...we stop defending ourselves?

This is like that bloody mafia movie..... 'Just when you think youse is out... they drag ya back in...'

Dear acum45... please use the search facility and look for the word radar.

Having half-said that.... yes I know they are powerful and frequent... I know they are necessary for defence... I would love to see us all disarm back to wet celery sticks but I am fairly certain that wont happen. So... what you cannot control... is out of your control. It doesn't mean that you should not try and avoid making matters worse.

Dear anthrage,

For myself, I think it would be a damn shame to refuse that challenge

I agree with you. But please note that under your scenario we would have more information than we have now... (even if confusing and conflicting).... again something that I advocate.

I am really off this time.......

[Anthrage]

Dear anthrage, I agree with you. But please note that under your scenario we would have more information than we have now... (even if confusing and conflicting).... again something that I advocate.

The point I was trying to make was that it will never be possible to be sure. Having more information does not change that. Regardless of what information you have, you will eventually have to make a decision - and the risk is exactly the same in an information rich scenario as in an information poor one. The risk does not change.

At some point, you have to decide. What will your decision be based on? What qualities must a civilization have for you to choose to communicate with them?

[WalrusLike]

The point I was trying to make was that it will never be possible to be sure....The risk does not change....
... What qualities must a civilisation have for you to choose to communicate with them?

Um... I think you have a good handle on the issues... but I must respectfully disagree... The risk analysis could be vastly different in an information rich scenario than a poor one. In some scenarios where you _do_ have information it could be very clear that saying hello would be a bad idea. Say for instance if you see the equivalent of video footage of their last three civilisation sackings....

Again... that is not really the point... at this moment in time... with no information at all... we would be unwise to sing out loud. Later we may have to face the issue that you refer to... and I understand your point that it may be difficult to know what is the best course of action. But that is not now. Pre-empting the decision by shouting is not a good policy.

What would want to make me say hello?... Simple... if it seems that there is a fair chance that they wont immediately attack I would vote for communication.

[NB: for the literal minded nit pickers out there.... the words 'immediately' and 'communication' are to be taken in the context of special relativity and galactic distances... not your irc chat session....]

[Anthrage]

There is a difference between 'risk' and 'danger' - the latter is what makes the former questionable. The danger level may be variable, but the risk is always the same.

That, I think, is the point. Whether we shout or not, the reason for not shouting is your danger assessment. As you yourself say, if there is a 'fair chance' they will not immediately attack, you would communicate. In my opinion, there is no difference between you making that determination then based on a fair chance, and those doing the shouting now making their decison on the same basis...that there is a fair chance they would not (immediately) attack; for the reasons previously mentioned in this thread.

The risk is the same. The decision - made now or then - is the same. Again I understand all you are saying, but I think you are overlooking the simple fact I have illustrated above. You just cannot escape the risk.

[EndeavorRX7]

Without making a long post, my stance is...

the possibility that they may have large teeth to shred us with is enough for me to say lets be quiet.

My point is I don't want us to become extinct.

[TheHalcyonYear]

Yes... I agree that we don't seem all that intelligent....

Folks... we are talking on an astronomy forum.... There are hundreds of billions of stars in our galaxy... they have been there for billions of years...

Oh WalrusLike, I think it's just that not many here take you or your concerns very seriously.

[Noclevername]

Oh WalrusLike, I think it's just that not many here take you or your concerns very seriously.

Not true. I take his concern seriously, I just think it's misplaced. Being that there's no evidence of any civilization whatsoever, hostile, friendly, or neutral, anywhere within listening range.

At the very least, the total destruction of a civilization would make some noise, wouldn't you think?

[WalrusLike]

The human animal is not very good at understanding probability... or risk. It rarely behaves rationally in the face of risk assessments.

Some folk are too afraid to swim out a ways into the ocean because they fear a shark attack. They are happy to _drive_ to the beach... and then _sunbake_. But they definitely prefer to stay in the shallow water... where its safe.

Most shark attacks happen in shallow water, they are at phenomenally small risk of ever being involved in any attack, the drive to the beach was much more risky..... and the sunbaking is straight out asking for it.... cancer I mean. (btw: I do swim, don't wear sunscreen, drive whenever I want to...)

The risk of shouting that I refer to is unknown... its likely small... but maybe not... and if ever realised then it could be the end of everything for us.

Now I am as bad as the next bloke at ignoring facts and doing dumb things... (like trying to convince you for instance... ) But I reckon that if we ask for a show of hands... those of us here that know how many stars there are, that know of the last decades' changes in perceptions of the goldilocks zone, that understand predation and selection pressures, that understand the enormous lengths of time that this old galaxy has been wheeling around, that are aware of the increasing number of indications of planetary systems, that are aware of the pitifully small zone of search in bandwidth and distance that Seti has so far achieved, that know how little the distance we are visible from so far.... if we ask those folk: "Who here thinks that they are alone... and always have been... and always will be, in the universe?" I reckon few will put their hand up.

Most of us think that there is a chance, at least, that we are not alone. At that point we seem to get all warm and fuzzy and turn off all critical thinking and rationality. (the argument of concurrency of sentience is perhaps germane... but no one knows)

To all those [insult deleted] who say... its no big deal... its not much of a risk... you are worrying about nothing... we are too far away in distance and in time.... I say: Yep you are likely right.

But that doesn't change the fact that a potentially risky behaviour is occasionally being undertaken without consent and without any weight being given to the potential downside.

It has been at least partially acknowledged, by a few so far, that my three points are basic and unassailable... and all the glib 'don't worry about it' statements still don't give anyone the right to shout out to the universe from the same rock that my family (and their descendants) inhabit.

Btw a civilisation could easily go out with a whimper ... not a bang. Haven't any of you folks read _any_ science fiction?? Only the space pirate kind?

Every thing that I have said is self evident... and I will be bombastic enough to say that if you don't accept it then you are not thinking straight. (and some clearly cant...)

[WalrusLike]

There is a difference between 'risk' and 'danger' - ... the risk is always the same.
...The decision - made now or then - is the same....

Mate I reckon that we are just arguing semantics here... risk/danger... call it what you will. The _fact_ remains that it is always best to know something about a situation before you jump in.

So if you ask me... (and I realise that few are... ), I would say... make the decision later... when more facts are in.

Even just allowing the seti search more time gives you an additional bit of information.... you have reduced the likelihood of there being many species available... for good _or_ ill. And if only one in a hundred species is truly dangerous then I would rather know that there are not too many around in our neighbourhood before piping up.

[Robonaut]

What would want to make me say hello?... Simple... if it seems that there is a fair chance that they wont immediately attack I would vote for communication.

Well, that would seem to settle things, then.

Since:

(1) There is no evidence of hostile life in the galaxy (well, except Earth ).

(2) A civilization would have to be far more advanced than ours to even get here to attack us.

(3) A civilization bent on destroying all life it enounters seems less likely than one not bent on destroying all life it encounters.


I'd say that there is a fair chance that they won't attack.

So, I'm glad we can now get your vote to continue our communication attempts.

[crosscountry]

ok, it's built. I'm going to start sending messages out. what should I send?

[weatherc]

Assuming a species has technology advanced enough to travel light years to get to us, it also stands to reason that they have the technology to see that we're here without us transmitting anything to them, whether intentional or unintentional. A species would only need technology just barely more advanced than our own to spot that this planet has life on it, and would only need to be a little more advanced than that to see that there is a civilization here.

Any species hell-bent on destroying other civilizations would have already spotted us and started making plans to wipe us out. Whether we send signals out or not is completely meaningless.

[Byrd]

Does anyone have anything to say about the three points I made?

I personally do not think that they can be successfully argued against.... and that the logical conclusion is that we should not be deliberately broadcasting our whereabouts.

So far I don't think anyone has spoken to those points.... but perhaps I missed it....

1) the signal degrades the farther it gets from Earth. There's less of it (inverse square law) and in addition it gets mixed with the random noise of the galaxy. At some point it becomes unreadable and indecipherable and at some point it's just a few random signals in the noise of the stars and galaxies and background radiation.

2) How do you know another civilization would be listening on these frequencies? We happened to pick them because they're convenient to us.

3) Unless they had our equipment, they couldn't actually read and recreate the signals in the format that we see.

4) by the time it reaches a star with a civilization that could say "wait! This is a coherent signal" and could figure out how to turn it into music and figure out that it IS music (they are unlikely to be humans, you know), and then tried to back track it (which would be very difficult in the noise of the galaxy) our sun might be long dead and cold and our race gone.

5) If there were nearby civilizations (75 light years or less away), we'd have picked up their signals. So something's gotta be farther out than that.

[Ara Pacis]

The premise of the OP is the Precautionary Principle.

In military terms, you base your threat assessment on capabilities, not intentions. If they are capable of detecting us (similar or more advanced) then they may be capable of reaching us eventually.

But why might they attack? The same reason we might attack them first: Preventative War. That is to say, get them before they get us.

[neilzero]

I don't think we should assume that no ET can come here, just because it is very difficult for us to leave our solar system even with reasonable advances in present technology. Some of our present technology was not even dreamed of by science fiction writers of a century ago; so it is not impossible that we will advance in the coming century far beyond our present expectations in the coming century in a few areas, some of which may be essential to interstellar travel.
It is also possible that ET could flood us with details of new technology leading to future shock. This could occur with a rather low data rate that persists 24/7. Neil

[WalrusLike]

The premise of the OP is the Precautionary Principle...you base your threat assessment on capabilities, not intentions. ...

Well said temple of peace. Quite right. There is no way that anyone can successfully argue against this premise. Of course that doesn't stop folk who know no better from doing so anyway. What bothers me is that some of them may be astronomers who will have a say in whether a message is sent.

[WalrusLike]

...
Since:
(1) There is no evidence of hostile life in the galaxy (well, except Earth ).

Lack of evidence is not proof of lack of existence.

(2) A civilization would have to be far more advanced than ours to even get here to attack us.

Not so. Slightly more advanced would do it. Way less advanced but capable of hibernation, or becoming spores..... folks you are thinking too anthropomorphically. Better at transport, worse at radio telescopy. Users of pre-existing technology without any understanding of its principles....

I am starting to wish there was some way to hold a pre-test on basic understanding of the issues before one is allowed to speak....

(3) A civilization bent on destroying all life it enounters seems less likely than one not bent on destroying all life it encounters.

It doesn't need to be a civilisation; it may not destroy all life... just those built by symmetrically constructed beings (its called xenophobia); and finally.... yes that is probably true.... but again, it doesn't alter the fact that there can be some who do want to behave like genghis khan. (we got em here on earth....)

I'd say that there is a fair chance that they won't attack.

Just like I have been saying....

So, I'm glad we can now get your vote to continue our communication attempts.

I wonder if it would make you laugh out loud if the bad scenario ever did eventuate..... actually it probably wouldn't be you that was affected... more likely our grandkids.

[WalrusLike]

1) the signal degrades the farther it gets from Earth.....

Yeah.... and?

2) How do you know another civilization would be listening on these frequencies? We happened to pick them because they're convenient to us.

I dont.

3) Unless they had our equipment, they couldn't actually read and recreate the signals in the format that we see.

Just plain wrong.

4) by the time it reaches a star with a civilization... our sun might be long dead and cold and our race gone.

True-ish.... or at least possible.... likely?? I don't know.

5) If there were nearby civilizations (75 light years or less away), we'd have picked up their signals. So something's gotta be farther out than that.

Again, not necessarily so. A truly advanced civilisation might have near to zero emissions and detectability. (is there such a word?? ) So you reckon that further than 75ly (and the assumption that there is nothing closer is possibly suspect) is beyond the scope of the discussion? I don't.

[eburacum45]

I don't think you have really thought through the radar issue. We are using these defensive transmitters with no intention of contacting extraterrestrial civilisations; but if any civilisation detects us, it will probably be because of our radar.

This means the messages sent out deliberately are a waste of energy; no-one will be able to detect them. Don't worry over much about the deliberate messages- they are irrelevant. It doesn't matter if we send messages or not- extraterrestrials will find us, if they are within range and they are looking.

It's like trying to hide with a flashing light on your hat.

[A.DIM]

Indeed, and perhaps ET (is) too bored by earth transmissions to respond?

I'll note that this article, a few months old, states there have been only four, 4, deliberate "shout outs" to hypothetical ET's from humans.

Again, it strikes me as cosmic paranoia in the face of the human spirit and unrelenting need to know our place in the universe.

[WalrusLike]

I don't think you have really thought through the radar issue.....It's like trying to hide with a flashing light on your hat.

Your right... perhaps I haven't. But our definitions of 'thought through' might be different.

Our radars are a thorn in the side of anyone wanting to keep a low profile till we know more.... but they are still a different issue than the targeted high power, high redundancy signals sent from radio telescopes.

Radars largely get beamed off in randomish directions in the plane (roughly) of our solar system. [nit-picker alert]

Messages directly target 'high' possibility stellar systems. That's a BIG difference right there. Radars are not always active. So its not a continuous beam. Chance to slip through the cracks there... [nit-pickers... yeah... I know... neither is the telescope message... but 1 shot is better than 2 shots. Its a game of chance.]

My whole argument rests on the fact that although things are not perfectly safe right now... we can make matters worse if we actively message. It shouldn't be hard to understand. (and yes, for the thousandth time, I agree there is no certainty in any of this..... except that caution is the best plan.)

Its like trying to lay low and avoid shouting when you have a pencil beam light on your head.... I agree its not ideal. But lets not make it worse.

[Robonaut]

Well said temple of peace. Quite right. There is no way that anyone can successfully argue against this premise. Of course that doesn't stop folk who know no better from doing so anyway. What bothers me is that some of them may be astronomers who will have a say in whether a message is sent.

To quote from the Wikipedia article "it [the Precautionary Principle] is considered by its proponents to be applicable only when, on the basis of the best scientific advice available, there is good reason to believe that harmful effects might occur".

So, I'd think that you'd have to prove that the best scientific evidence indicates that there is a threat, which (based on my limited knowledge) I don't think it does.

Still, I'm getting the impression that you may be just a troll and rational discussion is pointless.

[Van Rijn]

Never mind about messages, which are single, short duration, highly directional beams; how about radar transmissions, which are more powerful and spread out in many directions? I live near a phased-array radar system which could be detected by Earth instruments thirty light years away. Are you suggesting we stop using that?
Are you in fact suggesting we stop defending ourselves?

Or worse than that, the oxygen signature in our atmosphere, which could be identified by telescopes not much better than what we have now. Again, a hypothetical star faring species that is that worried about other technological species could have wiped us out long ago, before we even had a chance to develop. Why assume they would wait until now to attack?