Existing Laser Technology Could Be Fashioned Into Earth's 'Porch Light' To Attract Alien Astronomers, Study Finds (mit.edu) 257
If extraterrestrial intelligence exists somewhere in our galaxy, a new MIT study proposes that laser technology on Earth could, in principle, be fashioned into something of a planetary porch light -- a beacon strong enough to attract attention from as far as 20,000 light years away. From a report: The research, which author James Clark calls a "feasibility study," appears today in The Astrophysical Journal. The findings suggest that if a high-powered 1- to 2-megawatt laser were focused through a massive 30- to 45-meter telescope and aimed out into space, the combination would produce a beam of infrared radiation strong enough to stand out from the sun's energy. Such a signal could be detectable by alien astronomers performing a cursory survey of our section of the Milky Way -- especially if those astronomers live in nearby systems, such as around Proxima Centauri, the nearest star to Earth, or TRAPPIST-1, a star about 40 light-years away that hosts seven exoplanets, three of which are potentially habitable. If the signal is spotted from either of these nearby systems, the study finds, the same megawatt laser could be used to send a brief message in the form of pulses similar to Morse code.
Is it a good idea? (Score:5, Insightful)
Any tribe that had such an idea in the 15th and 16th century would have been run over and destroyed before they even know what was happening.
Why would you assume the aliens will be any less brutal than the 16th century European explorers?
Re:Is it a good idea? (Score:5, Insightful)
It wouldn't even be that close. It would be like if we had another 500 years to develop our military technology, and these were people who had never even seen electricity harnessed before. We show up with fucking mech walkers and sniper rifles with 2 mile ranges and fighter jets that are naked to the human eye and they're throwing rocks and sticks at us.
Any alien that can come say hello would be so far out of our league we'd be like ants to them - barely smarter than the monkeys and dogs and kangaroos around us as far as they're concerned.
Re:Is it a good idea? (Score:5, Funny)
Well I didn't have my coffee. I meant fighter jets that are *invisible* to the *naked* eye.
Though jets with giant dongs would be similarly terrifying I suppose.
Naked Jets sound awesome (Score:2)
Rather than jets with bits hanging out, I was imagining jets with no visible skin, just a horrifying skeletal framework flying impossibly through the sky, with a guy in a skull hemet inside grinning down at the burning landscape below.
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Geebus, stop thinking of Aliens as some kind of blob. Think more, this generation of Aliens, those Aliens alive today. So why the fuck would a society evolve all at once, we haven't, huge difference in social development across the world, as for other far more evolved societies, probably maintain primitive worlds for their less evolved counter parts. Straight up logic theory, unless you alter your conflict resolving basis as you technology evolves, so you will cause yourself to go extinct, simply inevitable
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You could argue that in order to have the technology to travel to another star they would have to have achieved a certain level of civilisation and understanding of the risks, if not the moral implications.
On the other hand they may decide that the safest thing is to hurl a big rock our way.
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You could argue that in order to have the technology to travel to another star they would have to have achieved a certain level of civilisation and understanding of the risks, if not the moral implications.
Yes, but you you can't guarantee that.
Obligatory xkcd (Score:4, Insightful)
What, nobody has posted the obligatory xkcd yet?
fish [xkcd.com].
... and also, are you sure we're looking for the right thing? ants [xkcd.com]
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This one too. [xkcd.com]
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3b) Disinfection - before the earthlings build von Neumann probes and become a nuisance to clean up.
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That's my thoughts. Great idea - turn on your porch light to let people know you exist. The problem is that we might be living in a bad neighborhood, cosmically speaking.
There might be things on the lookout for a nice habitable planet. Not what we want to attract.
Re:Is it a good idea? (Score:5, Insightful)
I have a hard time imagining the mindset of someone who thinks interstellar civilizations will be like Vikings, but with space ships.
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I have a hard time imagining the mindset of someone who thinks interstellar civilizations will be like Vikings, but with space ships.
Do you also have a hard time imaging the mindset of Vikings ?
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Earth laser Smoke Signals the nearest star, Alpha Centauri.
8.6 years later, Earth receives Alpha Centauri smoke signal.
Earth telegraphs: Hi
8.6 years later, Alpha Centauri telegraphs: Hi
Earth sends: We are people of Earth, we bid you welcome.
8.6 years later, Alpha Centauri sends: Go away, yer too bloody boring, and stop wasting our time. You won't be on our white list from now on.
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If there were an alien race so advanced as to be able to travel huge distances to the tune of thousands of light years then they wouldn't care less about the Earth because with their abilities they could travel to and harvest any other much closer planets which we've found aplenty. You just cannot even fathom such an advanced civilization.
In fact a lot of scientists think that we're not alone in the universe b
Re: Is it a good idea? (Score:2)
How often do you stop to talk to ants? Do you even treat ants as intelligent? That's what we might be for intergalactic spacefaring civilizations.
If an ant shone a fucking laser beam in my eye, yeah, I'd stop and have a chat with him ...
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Because explorers were brutal for profit. Given the physical limits of our universe (like the speed of light in a vacuum), there's no conceivable profit motive for crossing interstellar distances to exploit Earth out of all planets.
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More likely, they won't even notice. (I hope, personally, for the same reasons you posted).
I'd made a longer blog post about this, but basically, if we say the universe is 15b years old, and our solar system took about 5b years to get here where we are, and lets even assume that the first 5b years of the universe it was a unique period with nothing productive happening.
This would mean that it's possible there were civilizations where we are today, about 5b years ago.
Assuming it's going to be a relatively t
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I'm guessing this bright idea was dreamed up by a bunch of enlightened progressive scientists who, of course, assume that any aliens who are intelligent enough to develop space travel must, of course, be enlightened progressive, too.
It's not clear which is more galling about these people. Their arrogance or their stupidity.
Re: Is it a good idea? (Score:5, Insightful)
It was literally the last warning from Steven Hawkings. History is full of examples of what happens when one civilization meets another civilization that is vastly ahead in technology. It has always ended badly for the ones with inferior technology.
https://www.sciencealert.com/s... [sciencealert.com]
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Seriously? You really should study a little history
Re:Is it a good idea? (Score:5, Insightful)
Humans are brutal in general, regardless of tribal identity or history. There's this weird recent idea that western=bad, primitive-people=good, and it's just as idiotic as the reverse that people used to believe. The Noble Savage and all that shit like you might see in Dances With Wolves. It's all a lot of malarky. It's hippie nonsense stemming from the belief that modern society is corrupt, and somehow living in caves was some wonderful, freeing thing where it was some great society.
Why does either extreme not understand human nature? Go read Lord Of The Flies. That's what humans are actually like.
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To be fair, a lot of the reason the focus is on "western=bad" is that the westerners generally had the greater power. People are more interested in condemning Hitler than in condemning a terminally ill homeless amputee with the same views and goals as Hitler.
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In the 20th century, Europeans were responsible for... perhaps 95 out of every 100 deaths by war, worldwide? Our ability to exceed our previous achievements in the craft of death/torture is.. impressive.
You forget the Sino-Japanese portion [wikipedia.org] of WWII, a significant fraction. If you got back before the 20th century, China tends to top the lists [wikipedia.org] as well. I imagine much of that is simply population.
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Humans are brutal in general, regardless of tribal identity or history.
And like everything, there are degrees. Europeans invented some of the most fucked-up torture devices ever constructed. Yeah, it's the past and I'm not condemning any living European for this bit of history (they weren't there). But to even imply that there aren't LEVELS of brutality is bullshit.
Our technology has given us the ability to kill more efficiently, torture more effectively, and destroy more completely. In the 20th century, Europeans were responsible for... perhaps 95 out of every 100 deaths by war, worldwide? Our ability to exceed our previous achievements in the craft of death/torture is.. impressive.
Don't give the Europeans so much credit. Sadistic ritual torture where the victim was tortured to death in the most gruesome ways imaginable was invented by the native American and African tribes long before the Europeans culturally appropriated it. Only through Eurocentric revisionist history can you give the Europeans the credit for inventing it. The Europeans may have made some devices of their own, but they were standing on the shoulders of giants.
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The Lord of the flies is novel and doesn't do human nature justice. Your the only one that brought of the concept of a noble savage. Heck, the island civilization was hypothetical. Nobody characterized it as anything other than ignorant about the world around it.
Hey, have an informative mod for responding to a point nobody made and using fiction as your argument.
Re: Is it a good idea? (Score:4, Insightful)
You've seriously never heard of the "Noble Savage" concept? Because it's a concept that criticizes the sort of thing you're upset about. I think you've misunderstood the comment you're replying to.
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This is the kind of post that I'd love to mod as "informative"
Comment removed (Score:4, Insightful)
Re:Is it a good idea? (Score:5, Insightful)
He is not calling non-westerns "Savages". He is referring to the LITERARY TROPE of the Noble Savage (and calling it stupid): https://en.wikipedia.org/wiki/... [wikipedia.org]
Try a little harder to be offended?
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It isn't just "savages", but any defeated society takes on a connotation of nobility, fierce, great fighters, and so on. In spite of the generally positive nature of the beliefs, it is a kind of reverse racism.
Crimean Warriors, anyone?
Re:Is it a good idea? (Score:5, Insightful)
> So why is AC still using the term "savages" to refer to non
> Western European cultures, and why the fuck are you defending the practice?
And why the fuck don’t you at least TRY to educate yourself on the term “Noble Savage” and it’s contemporary usage which is exactly criticizing the pseudo-positive racism, colonialism and paternalism that is inherent in the combination of those words.
Bah, all hope is lost if even people on your side of the trench can’t be bothered to think.
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Re: Is it a good idea? (Score:2)
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You're still brutal. Brutally ignorant.
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They may just not have been technically advanced enough to have enough spare time to come up with those ideas.
You need a proper, stable food supply to afford people whose only job is to invent means of torture.
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This is just fantasy. The most advanced rockets in the first half of the 20th century were developed by the Nazis. The USSR, not exactly known for its advanced personal cooperation, nor free of torture devices, was the first country to put both a satellite in orbit and a human in orbit. Only a massive effort by the U.S. with cooperation from a handful of other countries allowed them to reach the moon first.
Intellectual capacity has absolutely nothing to do with moral orientation. Slavery is not used in west
Re: Is it a good idea? (Score:2)
Re: Is it a good idea? (Score:2)
Look at some of the shit France did in Vietnam during the colonial period. No wonder they fought for their independence and reunification for like 40 years until it happened.
That's a cute way of putting it. Meanwhile, in reality, the war in Vietnames starting with the French involvement was very much a civil war quite similar to the one in Korea. Communists in the north vs a democratic republic in the south, with Russia and China supporting their commie brothers while France (and, later, America) tried to prop up the democraric south.
Sure, the French did some horrible things. So did the Americans. Any brutality displayed by either of those participants pales in comparison t
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The French were in Vietnam before Marx was even born. They did not go in to prop up any form of democratic government; they were already there running the place through a puppet monarchy.
Do you think
Re: Is it a good idea? (Score:2)
Well if you want to go that far back, you'll have to be more specific about which bits of history you're referring to. French militray assistance to varuous Viatnamese royals in the late 18th/early 19th century? The French kicking the Chinese out of Northern Vietnam? The Vietnamese royalty requesting that Vietnam be a French protectorate? The Cambodians requesting the same thing? The Japanese conquest of French Indochina? The defeat of the Japanese and reestablishment of French control?
Are you under s
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Re: Is it a good idea? (Score:2)
Re: Is it a good idea? (Score:2)
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If Extra Terrestrials exist... (Score:5, Insightful)
If we're not alone in the universe- I would like to know about our neighbours before they know about us.
Sending an unsolicited welcome beacon into the night could be catastrophic. If they're able to read it and respond they're probably more advanced than us. If they're more advanced than us they might not want to share the galaxy with another species who one day might evolve to challenge them or threaten them. There is no guarantee that any aliens out there would share our sentimentality to life. Or even want to meet alien species.
If their civilization has advanced far enough to be guided by Artificial Intelligence, certainly AI would decide the logical thing to do is remove a future threat before it becomes a threat. This isn't Star Trek, you can't guarantee that Mr. and Mrs. Greenface want to drink Romulan Ale with you and be best buds with you. Any species that survives to the space age needs some logic. Logic will tell you intelligent alien species could be a potential threat.
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Profile of intelligent aliens.
Based on what we know about animals on earth: the animals that are most intelligent are usually hunting animals; they may be omnivores, but by and large, most of the intelligent animals on earth do some hunting. (there are exceptions such as elephants of course). In general, to be a successful herbivore you need to be able to hide, or you need to be able to run fast. To be a successful predator or omnivore, a little intelligence can help.
Think humans, chimps, dolphins, pigs,
Re:If Extra Terrestrials exist... (Score:5, Funny)
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Maybe they've evolved past needing meat and became vegetarian! Then they'll come to Earth and never shut up about it.
All the more reason not to advertise our location to them.
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Yeah that little eugenics intuition "seems right" but guess what? it isn't.
The fact is, the thing that separates us most from animals, what makes us "more intelligent" than them, is the very fact that we started farming. Growing our own food. The perversion of farming living things came later and was a step back. Ebb and flow and all.
The increase in calories allowed us to have more for stoking our brains; but the fact is, we evolved from already smart creatures. Chimpanzees aren't farmers and they're already close to us in intelligence. I think that the ability for us to start farming is proof of intelligence already existing.
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It seems to me that logic doesn't give a clear answer, as (1) cooperation may help your civilization to grow and exploit more faster; development is not a zero sum game; (2) any alien civilization should also expect that there is probably out there a more advanced alien civilization that it would need to compete with, and it might aid and use ally itself with smaller threats to defend itself against the larger threat. Ultimately, which approach is taken would probably be decided more by the context in which the alien society evolved.
When it comes to gambling the future of humanity- I tend to be risk adverse. I'd rather carry on with the status quo of no alien interference than gamble that they might help progress us (with the flip side being that they might wipe us off the face of the earth).
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Assuming the extra terrestrial life is well more advanced than we are, it stands to reason that they can detect us whether we broadcast a beacon or not. Given sufficient technology to travel between star systems, they probably have sufficient technology to properly scout out star systems before starting the journey...
That's a serious ping time (Score:3)
a star about 40 light-years away that hosts seven exoplanets, three of which are potentially habitable. If the signal is spotted from either of these nearby systems, the study finds, the same megawatt laser could be used to send a brief message in the form of pulses similar to Morse code.
So this would be an 80 year round trip ping time? Someone far away would also have to be looking our direction when we light it up. For argument's sake let's say we want to allow a 10 year window for someone to notice our beacon. This means that we would have to shine the beacon for 10 years and then wait up to 90 years for a response?
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Only if they don't have faster than light travel or communication ability. But definitely 50 years minimum, again if we rule out that they can move backward in time.
Re:That's a serious ping time (Score:4, Insightful)
That's okay! It's only 1 or 2 megawatts continuously for those 10 years!
That's only $21 million in electricity costs alone, and 100,000 metric tons of CO2 added to the atmosphere. Surely, that's a small price to pay to be good celestial neighbors...
Re:That's a serious ping time (Score:5, Insightful)
That's okay! It's only 1 or 2 megawatts continuously for those 10 years!
That's only $21 million in electricity costs alone, and 100,000 metric tons of CO2 added to the atmosphere. Surely, that's a small price to pay to be good celestial neighbors...
So.....just the equivalent of a handful of bitcoin miners? That's not too bad.
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Yeah,
and we have to take into account that we and the other solar system are moving, so we can not aim directly at it but where it will be in 40 years.
why not both? (Score:2)
Remember Stephen Hawking's warning (Score:3)
ergo, I am smarter that Stephan Hawkwind (Score:2)
Re: Remember Stephen Hawking's warning (Score:3, Insightful)
That's where he was wrong; it turned out very well.
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“Meeting an advanced civilization could be like Native Americans encountering Columbus. That didn’t turn out so well.”
You mean we'd become the casino planet?
Morse code? (Score:2)
My ISP gives me internet via Laser fiber, those guys need to read up on current technology.
They could send the encyclopedia galactica every second if they use all the possible color and other channeling methods.
Use morse for the decryption manual as header.
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Google Shannon-Hartley capacity theorem.
DON'T FUCKING DO IT (Score:5, Interesting)
Read "The Three Body Problem" before you talk about this shit.
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I have. Have you read The Three Body Problem?
Random phone call... (Score:2)
...Calling all borg, transformers, etc...
First Contact in 45 years (Score:2)
Other than Halloween my porch light is off (Score:2)
Have you ever actually seen what gets attracted to a blazing porch light?
You get large amounts of Bugs, and if you're lucky, some bats or spiders come to eat them.
If we're doing an Intergalactic Porch Light, I'd hope someone would plan on a nearby bug zapper.
Re: Other than Halloween my porch light is off (Score:2)
You get large amounts of Bugs
No problem; by the time they get here our Starship Troopers will be ready and waiting.
The 3 Body Problem (Score:2, Informative)
If you want a awesome book series about this exact type of thing, I recommend `The Three Body Problem`. It's a great book to get into (translated) Chinese scifi literature
What could possibly go wrong? (Score:2)
Porch lights attract bugs (Score:2)
Porch lights attract bugs and it usually doesn't end well for the bugs. ...
On the other hand, those bugs don't have interstellar flight capability and, presumably, particle weapons
Generating new light? (Score:3)
Wouldn't it be a better idea to focus the gigawatts of excess solar energy our planet is absorbing every day, and help fight climate change at the same time?
40 light years. (Score:2)
Soo.... assuming we build this thing , we 'might' know if it works in 40 years + whatever time it takes a civilization to recognize it and try to reply ( assuming WE recognize their reply), but say it is really fast they find the signal then reply really quickly we can expect the message to take a minimum of 40 years to get there. So basically build it. Wait 100 years, before you can even BEGIN to reasonable expect a reply. ( that of coarse covers the first 2 possible planets which we have no evidence ac
the earth is a black light trap (Score:2)
let them come, and we'll devour them.
wait, they'll probably decide to put an intergalactic highway system here.
chance of success - infinitesimal (Score:3)
"Such a signal could be detectable by alien astronomers performing a cursory survey of our section of the Milky Way -- especially if those astronomers live in nearby systems, such as around Proxima Centauri, the nearest star to Earth"
The good people at MIT seem to have overlooked a small detail. Space is really big. Douglas Adams discovered this long ago- please bone up on your studies.
In order to scan the universe with your narrowly focused telescope, you need to be able to see a width of 360 degrees and vertically at 360 degrees. Virtually an infinite number of adjustments in both directions. In order to see the puny laser beam, you'd have to pause your telescope in that direction long enough to identify it and separate it from nearby noise; perhaps for a few seconds(10?) If every position of the telescope requires 'a few seconds', it would take an extremely long time to scan the universe.
From the other perspective- if you want to point your laser to every point in the sky, you have the same problem. A nearly infinite number of points, depending upon the width of the beam. If you are sending some kind of signal, let's say a burst that takes a few seconds (10?) in each direction, it would take an extremely long time to beam across the universe.
What are the chances that your beam and the telescope at the other planet will meet?
Infinitely small.
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Ah, but suppose you aim your beam at a specific planet that seems as if it might possibly support life? Well, now you can aim your beam right there! But first, you have to remember that you are seeing the star/planet as it was a long time ago. You have to calculate from its heading where it might be when your beam arrives, far into the future. That seems possible. But then you have to correct for every gravitational field and other anomaly between here and there that will bend your beam and send it off in a
Its too early (Score:5, Interesting)
Here are some possible outcomes:
They are dangerous and if they come here they have better technology than we do - we're screwed.
They are nice beings, but correctly conclude we are not. They decide its better to eradicate us before we become the scourge of the galaxy - we're screwed.
They are curious but see no benefit in engaging with us directly
They are not curious and correctly conclude we have nothing to offer their more advanced society. The universe is a big empty place and there is space enough for everyone.
My personal favorite - faster than light travel is fantasy and they will never bother to come.
In any case, the likelihood that they are wondrous benevolent beings who want to give us all kinds of nice stuff without unintended consequences is basically zero. No need to attract attention. Do something useful instead.
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"In any case, the likelihood that they are wondrous benevolent beings who want to give us all kinds of nice stuff without unintended consequences is basically zero. No need to attract attention. Do something useful instead."
I would add, is probably the result of a residual idea of wanting a God or gods to come to our aid and explain the universe to us.
We Subgenii have a saying: (Score:3)
"DON'T Pray. You never know what might be listening."
It would be a monumental effort, but perhaps a less dangerous method might be to set up the laser in the Centaurus system. That way, if any "bad people show up" (cf The Beastie Boys), they might not notice us. Too bad if there are any intelligent Centaurans, but they should have thought of this first and put a laser in OUR system.
Don't be the guys on the shore (Score:2)
At least in recent human history, when the guys in the boats meet the guys on the shore, it doesn't end well for the guys on the shore.
When we have the technology to travel interstellar distances, I'm happy with the idea of trying to meet new friends.
The Dark Forest Theory (Score:2)
Alien astronomers? (Score:2)
Re:Yeah, just what we need (Score:4, Interesting)
Well, if the laser is red, you can hardly blame the aliens for 'red light district' being an universal concept. And if it is not, then we should not risk advertising our present with other hues, either.
Basic prudence dictates that we do not attract attention to ourselves before knowing what that attention will bring along.
Re:Yeah, just what we need (Score:5, Informative)
-Zoe, Firefly (2002)
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"Of course they're cute NOW. But in a second they're going to turn MEAN and UGLY somehow and then there are going to be a million MORE of them! ... Jesus, didn't ANY of you watch the show!?"
-- Guy Fleegman, Galaxy Quest [scifiscripts.com] (1999)
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We STF don't want to attract any Reavers!
Re:Yeah, just what we need (Score:4, Interesting)
Agreed.
Let me link you the Fermi Paradox: We're First, We're Rare, or We're Fucked.
https://waitbutwhy.com/2014/05... [waitbutwhy.com]
Specifically Possibility 4: There are scary predator civilizations out there, and most intelligent life knows better than to broadcast any outgoing signals and advertise their location. This is an unpleasant concept and would help explain the lack of any signals being received by the SETI satellites. It also means that we might be the super naive newbies who are being unbelievably stupid and risky by ever broadcasting outward signals; and Carl Sagan's takeaway: “the newest children in a strange and uncertain cosmos should listen quietly for a long time, patiently learning about the universe and compa, ring notes, before shouting into an unknown jungle that we do not understand.”
Re:How much RF energy do we broadcast? (Score:5, Informative)
That's indistinguishable from background noise a few light years out. Hence the entire point of this study on how to purposefully send a signal that is distinguishable at a distance.
No. Check your facts.
He's correct: our RF broadcasts are indistinguishable from background noise at even a few parsecs distance. The stars turn out to be a very very long way away.
There are two exceptions: the Arecibo planetary radar, and ballistic missile warning radars.
But the Arecibo dish is very rarely used as radar, and if it did by coincidence happen to illuminate a star with inhabited planets behind the planet it was looking at... it's likely that it would never point that direction again, ever. The aliens would see one bright blip--if they were looking with an Arecibo sized radio telescope at the right frequency at exactly the right time--but if they look again, nothing.
Ballistic missile warning radar would be more repeatable, but it sweeps small parts of near-polar sky with a repeat time of 24 hours. So, if they see the blip as the radar passes over their star, unless they look again exactly 24 hours later, again, they won't see anything.
And, at a hundred parsecs, even those signals are too faint to detect-- they're swamped by the background. The galaxy is 100 thousand parsecs across. So, no: most of the galaxy couldn't hear us even if they had Arecibo-sized telescopes listening.
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Well, it will be a few 100 years before they get here. Hyperspace only exists in TV land. Wormholes require a black holes worth of energy to keep open.