Astronomers: Please stop shouting out to the universe.

[Drunk Vegan]

There are only two conceivable scenarios where it is safe to initiate communication with an alien race:

1. The aliens have directed a signal at us. The content of the message (or the transmission method itself) confirms that they are aware of our presence and are speaking to us directly. Since they already know we are here, we risk nothing by responding.

2. We have observed (through telescope or by overhearing their communications) that they are at a technological level that is inferior to our own, and therefore do not pose a threat. This however is not entirely without risk, because:

a) in the years that it took light to reach your telescope, they may have already developed technologies vastly superior to your own
b) Supposing that their technological development was halted, it's still conceivable that by exposing your position you may enable future generations to find and destroy you.

Personally I don't think it's worth it to initiate contact until we have a colony elsewhere that can bridge the gap. At least if our visitors are hostile they will only end up obliterating a colony and not the entire human race.

[Van Rijn]

There are only two conceivable scenarios where it is safe to initiate communication with an alien race:

1. The aliens have directed a signal at us. The content of the message (or the transmission method itself) confirms that they are aware of our presence and are speaking to us directly. Since they already know we are here, we risk nothing by responding.

How close are they, and what are they aware of? If you are going to be paranoid, I think one could argue that we should not provide any additional data. A directed response in itself would give ET more information.

2. We have observed (through telescope or by overhearing their communications) that they are at a technological level that is inferior to our own, and therefore do not pose a threat. This however is not entirely without risk, because:

a) in the years that it took light to reach your telescope, they may have already developed technologies vastly superior to your own
b) Supposing that their technological development was halted, it's still conceivable that by exposing your position you may enable future generations to find and destroy you.

Personally I don't think it's worth it to initiate contact until we have a colony elsewhere that can bridge the gap. At least if our visitors are hostile they will only end up obliterating a colony and not the entire human race.

By "colony" do you mean an interstellar colony? So, am I right that you think we should never send out any signals until and unless we expand to at least one other star? In short, no SETI transmissions, within, optimistically, several centuries?

By the way, notice that if ET follows the same rules, we're only going to hear from interstellar civilizations, assuming, of course, that they exist and that they even care about such things.

[NGCHunter]

Fear mongering. Makes no sense. May as well say stop exploring, burn the telescopes, stop tv and radio broadcasts, build bigger bombs. Live in fear.

I'll give you my telescope when you take it from my cold, dead hands!

[Insert photoshop of Charlton Heston hoisting an antique telescope over his head]

[SolusLupus]

I hate to chime in here on the side that's unpopular (actually, it seems lately I do that all too much), but I think there is a point here.

Deliberately sending a message... well, what messages we do send don't really get far if they aren't exactly focused, and they are very energy-expensive. I'm all for keeping our ears open, but sending out powerful energy-expensive messages at this point don't really seem efficient. I don't see the harm in waiting a few decades to centuries until we've at least partially mastered our own solar system before we start broadcasting to others.

That's just my $0.02, unmodified for the inflation rate.

And, just before people start making assumptions, no, I'm not paranoid. I can see why some people would be cautious in broadcasting to other races, but the way I see it, if they can expend the resources to get to Earth, they have the resources to get whatever resources they need from other methods that don't involve such long journeys.

[peteshimmon]

I still do not know if this has been pointed
out but it is all a non-problem..or not.
The powerful beamed signals to interplanetary
probes were directed to fixed points on the
celestial sphere. They were not deliberate
"here we are" stuff, just complex fast
changing electromagnetic energy. And completely
artificial. Detectable for 100's of lightyears
I suppose. And they will continue. So it is
no use worrying.

[Van Rijn]

Deliberately sending a message... well, what messages we do send don't really get far if they aren't exactly focused, and they are very energy-expensive.

Our missile radar is quite obvious, and covers a large chunk of the sky. And, an advanced ET woudn't even need that. Gathering photons is much easier than building starships, so an ET species that could hurt us would have been aware of life here for a long time. From a paranoid species' point of view, it would make sense to hit any planet with complex species, to keep them from ever becoming a problem.

[SolusLupus]

Our missile radar is quite obvious, and covers a large chunk of the sky.

For light years and light years? Or for an infinite distance?

What range, and what stars could it get to, and not find it hard to filter it from background radiation?

Plus, if alien races from hundreds of near stars could spot us by our missile radar... what's the point in purposefully sending signals, then?

And, an advanced ET woudn't even need that. Gathering photons is much easier than building starships, so an ET species that could hurt us would have been aware of life here for a long time. From a paranoid species' point of view, it would make sense to hit any planet with complex species, to keep them from ever becoming a problem.

Sure, that's perfectly logical; we could also wipe out all the weaker nations like Africa to make sure they never become a problem, too. We could also wipe out, say, all the small countries before they develop a significant military. There are some that have no significant military in any way, shape, or form; logically, we should bomb the crap out of them or invade them. Just to make sure, you understand.

For your perusal, I propose we wipe out these countries that have no armed forces.

I guess I just don't see the logic -- and don't see how any species at all could arrive at this as a logical conclusion -- in going out of our way (or for any alien species to go out of their way) to attack another planet. The primary reason war and fatal competition has ever occurred here on Earth (and I'm not going to think that natural selection would work any differently on an alien planet), is because of competition for resources. However, there are far more resources in space than could successfully be harnessed by us today; and unless there's an alien race every other solar system, a species could expand and expand without ever bumping into another, and even if they did bump into each other, it just makes more sense to share what is otherwise an overly large amount of resources.

You'd have to be paranoid to the point of extremes to want to attack that small rock many hundreds of light years away "just in case" they happen to take you over for your limited amount of resources.

And a race that extremely paranoid would be too busy knifing each other in the back "just in case" the other guy thought of doing the same thing.

[Van Rijn]

For light years and light years? Or for an infinite distance?

What range, and what stars could it get to, and not find it hard to filter it from background radiation?

It's been discussed earlier in this thread and others - powerful radars have been painting a good chunk of the sky since the middle of the previous century. Detection range would be dozens of light years at least, depending on how big a receiving antenna is used.

Plus, if alien races from hundreds of near stars could spot us by our missile radar... what's the point in purposefully sending signals, then?

To say something more interesting than "blip!"

Sure, that's perfectly logical; we could also wipe out all the weaker nations like Africa to make sure they never become a problem, too. We could also wipe out, say, all the small countries before they develop a significant military. There are some that have no significant military in any way, shape, or form; logically, we should bomb the crap out of them or invade them. Just to make sure, you understand.

For your perusal, I propose we wipe out these countries that have no armed forces.

I guess I just don't see the logic -- and don't see how any species at all could arrive at this as a logical conclusion -- in going out of our way (or for any alien species to go out of their way) to attack another planet.

Well, that's been the argument against active SETI - that a paranoid ET would destroy us if we said "hi!" If you're arguing against the paranoid ET position, then what other reason would there be to avoid sending out signals?

[HypothesisTesting]

I concede that one probable reason they haven't done so, is because they think that if they do then the whole idea will die the death of a thousand committees. However, if they truly think there is a chance that they will contact alien intelligence, then they should take that as a globally significant event, and involve more than just everyone within earshot of the tearoom before doing something so profoundly significant.

You are right on here WL. Think of all the really big decisions both in science and other walks of life, how are they made? By popular consensus? No way. Certain people realize that they are in positions of authority/power, and decide to do things within their group. Their attitude is, we'll just go ahead and do this, what is the population going to do about it? And therein lies the attitude behind all the significant events in history, and certainly will continue within our lifetimes. I truly wish this wasn't the way the world works, but it is.

[SolusLupus]

Well, that's been the argument against active SETI - that a paranoid ET would destroy us if we said "hi!" If you're arguing against the paranoid ET position, then what other reason would there be to avoid sending out signals?

Mainly, the cost of resources, energy, funding, etc.

12 light years is a good distance, at least. That would hit 26 solar systems, going by this link. Although it would take quite a while for them to get there...

I'm having trouble finding out the cost of SETI's operation through funding. Can anyone come up with any figures, or at least point me in the right direction?

[HypothesisTesting]

I'm having trouble finding out the cost of SETI's operation through funding. Can anyone come up with any figures, or at least point me in the right direction?

It might be quite high because for some reason NASA seems to have dropped SETI and made private people like the Planetary Society and Paul Allen fund it. This seems ridiculous to me, because what more important could NASA be funding?

[Amber Robot]

This seems ridiculous to me, because what more important could NASA be funding?

Pretty much everything else that NASA is doing.

[crosscountry]

agreed. we are learning about our universe. That gets first priority. Searching for space aliens is secondary.

[01101001]

It might be quite high because for some reason NASA seems to have dropped SETI and made private people like the Planetary Society and Paul Allen fund it.

The SETI Institute's pretty cheap, as space exploaration programs go.

Space.com: With NASA Budget Cuts Looming, SETI Eyes Private Funding (October 2006)

But the center's immediate goal, according to Scott Hubbard, a visiting scholar at Stanford University and the Carl Sagan chair at SETI, is raising $4 million to $6 million over the next three years to sustain its top astrobiology researchers. Hubbard, the former director of NASA Ames Research Center, said about half of the institute's $14 million annual budget comes from NASA in the form of competitively awarded, peer-reviewed research grants.

[cogswell_cogs]

But we've been broadcasting our likely existence for millions of years using a transmitter the size of earth powered by the sun's energy. If an alien civ cared to examine the light, they'd find plenty of clues we were here anyway. If they are close enough, they could even see signs of our recent industrialization without ever leaving their home.

I'm not really a fan of active SETI but to be fair, if they are actively searching (and anywhere near us and biologically like us), they suspect this place already.

[WalrusLike]

..could even see signs of our recent industrialization without ever leaving their home.

I'm not really a fan of active SETI but to be fair, if they are actively searching .....they suspect this place already.

What you have said is true to a certain extent... but to say that 'we are detectable' and "they suspect this place already' is not the same thing as 'I am going to deliberately send a high power signal focused as much as possible directly to you.'

Just at this minute we don't know very much... but we may find that life is endemic... so the signals you referred to earth broadcasting over millions of years might not be all that significant. Maybe there are a billion such planets.

Lets assume that we are not special and that life on earth is not either... Lets say that you were looking for intelligent life in amongst 200 billion systems... of which maybe as much as one in a hundred have signs of life. That would give you 2 billion places 'broadcasting' in the way that you mentioned. And given that we are a very ordinary stellar type... it may be a much higher number...

Contrary to popular belief the TV signals that we broadcast wont be detectable out very far. The military radars much more so... but they are not broadcasting in every direction.... since we orbit in a plane and they are mostly in the northern hemisphere there is a large area of southern sky that doesn't often get shouted at by radars. Even in the north there are periodicities to take into effect and limits to the amount of activity over a certain latitude... *yes I know that the 'wobble' of precession and seasonal variation comes into it too...

The point is, that just at this particular decade we haven't got much info about the basic parameters in the Drake Equation, though the floodgates are soon to open with a number of new earth and space based scopes coming online soonish.

So what is the hurry about shouting out? How can they say 'I must do this now!'... when they know that an answer is going to take at least decades, and more likely, centuries, to come back.

What's the hurry?? Why not wait until some more facts are in... just in case the baby crying in the woods scenario is correct. Its not likely... but it _IS_ certainly possible. (it does at least offer an explanation of the Fermi paradox)

[cogswell_cogs]

Yeah, if life is somewhat common then we are hidden better. Otherwise we stick out in the sky.

I'm certainly no fan of active SETI and if there is to be any caution about it it's likely something astronomers and scientists will need to decide informally. I can't imagine any lawmakers or the UN addressing it. Not that I think the signals sent to date constitute much of a risk.

[Neverfly]

There isn't a hurry really.

You're making these implications and fearful comments about "Who Knows?!" But in the end, you're outnumbered by those that do not feel that we are facing a threat from space.

I do Not Know if:

I will get struck by lightning.
I will get into a car accident that I was not at fault.
I will develop cancer.
My son will be placed in a dangerous and potentially situation while at school (e.g. gas leak)

I don't stop going outside, driving or sending my son to school though.

[crosscountry]

this is still going?

[clint]

I do Not Know if:

I will get struck by lightning.
I will get into a car accident that I was not at fault.
I will develop cancer.
My son will be placed in a dangerous and potentially situation while at school (e.g. gas leak)

I don't stop going outside, driving or sending my son to school though.

That comparison is not really fair, though:
the risks you're describing only involve you and your son.

It's more like investigation of stem cells, cloning, nuclear power, nanobots, etc.
(which all have both potential risks and benefits for all mankind)

[WalrusLike]

That comparison is not really fair, though:
....

Thank you Clint for being a fair minded observer there.

Additionally I would point out that there are many large downsides to not taking the risks that Neverfly mentioned... being stuck forever inside without schooling... missing out on life outside the home etc.

So once again... a glib straw man argument.

The downside to not shouting is simply that you might potentially add a few years or decades to first contact. Something that already is virtually guaranteed to be at least a few, and maybe many, decades in the future anyway.

This is a simple case of an easy step to mitigate an unknown risk that has a potentially huge downside... Dont shout... wait and see what we learn in the next decade.

As far as I can see the only reason that you would disagree with this premise is if you think that
a) all aliens will be friendly
or b) that it is impossible to harm us over interstellar distances
or c) that there is no chance anyone is out there.
or d) that if they are there, they MUST know about us anyway

In any case... if there is any doubt... why shout?

[Van Rijn]

Contrary to popular belief the TV signals that we broadcast wont be detectable out very far.

That's also debatable. Usually, the calculations assume essentially current technology with currently available antennas. Here's a different view:

http://contactincontext.org/cic/v2i1/lucy.htm

Where he discusses bigger antennas and better technology. Detection range of TV signals is always far greater than decoding range, but he also considers what might be done with signal redundancy, so according to this argument, decoding range may be 100 light years or so. Detection range would be far greater than that.

[Neverfly]

The point of my 'risk comparison' was not about WHO is involved but of how minimal the chances of WalrusLike's Fear Mongering claims are.

What it comes down to is that We're it. We are all that we see. There is no hint, no sign, no indication that there is any intelligent life anywhere near us.

In order to entertain the idea that we are inviting disaster upon us, one must also entertain odds that are so slim, that it becomes almost irrational to entertain them.

There is a slim chance that My Great Great Grandson, far off in the future, is going to turn out like another Hitler and kill millions.
But I'm not going to take my son in for a vasectomy when he turns 13 years old.

WalrusLike's claims are based on Fear of a Completely slim chance that maybe there might could be some possibility of us inviting disaster by sending out Radio signals.

Well Too Bad. To me, entertaining that notion is just plain too irrational to bother with. I may as well sit here fretting and wringing my hands and worrying about whether or not the Apollo Astronauts caused us to be noticeable, or the Space shuttle causes us to be noticeable or a possible mission to Mars causes us to be noticeable or the Many probes we have sent out that leave the Solar System that might by some tiny chance smack into a Darfoonian Death and Enslavement Freighter from Draco VII and they will head for Earth to doom us all...

Come On!

Someone's been watching too much Sci Fi Channel.

[crosscountry]

Thank you Clint for being a fair minded observer there.

I find it funny when we think people are fair or balanced just because they agree with us. That makes them even less fair or balanced in my opinion.

That is the problem with people that watch one of the cable news stations - they only want to agree with something and don't care if it is fair or balanced.

[Neverfly]

I find it funny when we think people are fair or balanced just because they agree with us. That makes them even less fair or balanced in my opinion.

That is the problem with people that watch one of the cable news stations - they only want to agree with something and don't care if it is fair or balanced.

This is a very astute observation.

[WalrusLike]

That's also debatable..........to this argument, decoding range may be 100 light years or so. Detection range would be far greater than that.

Good find Van Rijn, well written, knowledgeable and interesting, thank you. Lou Scheffer is also active on Wikipedia in this area.

So lets look at how it affects my argument... Well, it certainly quantifies the possible ranges somewhat. But as far as I can see the actual range is not the issue... range just means time.

It comes down to... ok... do I care about consequences to my children? Sure I do. Do I care about my grand kids? Sure. But how far does it stretch? Range means time... and after a certain distance in time most folk just don't care about consequences... (often, even within their own lives and actions...)

My point is that unless there is an imperative to do so... any risk that could potentially affect all life on earth should not be taken even if the consequences wont be felt for a thousand years. If there was a clear benefit to the shout then the risk benefit calculation would be more problematic... but at this time a common sense approach would say... wait and see.

One thing that he doesn't delve too deeply into is: What does our broadcast zone map look like? I believe, and I so far haven't seen evidence to the contrary, that we do not broadcast symmetrically. That means that there are quieter areas and noisier ones. If we shout we do two things... we tremendously increase the range of possible detection, and significantly, we potentially shout towards a zone in which we have thus far been quiet.

All of these factors have significant uncertainties and so it just seems to me that deliberately shouting when there is no need or imperative to do so, does not make sense just as we are starting to unravel the facts about the nature of life and intelligence in our neighbourhood.

I honestly think that any reasonable person would have to agree that there is a faint chance that a shout could go to a place that we haven't previously alerted to our presence. Otherwise why the need to shout? So there must be some element of risk there. Given that ... isn't the onus on the shouter to make the case why it must be done... and done just now?

[RedFive]

I find it funny when we think people are fair or balanced just because they agree with us. That makes them even less fair or balanced in my opinion.

That is the problem with people that watch one of the cable news stations - they only want to agree with something and don't care if it is fair or balanced.

Which one..? They're all pretty darn unfair and unbalanced if you ask me.

[clint]

I find it funny when we think people are fair or balanced just because they agree with us. That makes them even less fair or balanced in my opinion.

Haven't agreed with anybody here

Comparing Active SETI with 'sending my boy to school' or 'driving my car' is just not very accurate,
regardless of what side of the debate you're on
(and don't even get me started on that vasectomy thing)