[HN Gopher] Sun-like star found in the region of the sky that ha...
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Sun-like star found in the region of the sky that has most radio
signals
Author : bewalt
Score : 49 points
Date : 2022-05-06 21:38 UTC (1 hours ago)
(HTM) web link (www.cambridge.org)
(TXT) w3m dump (www.cambridge.org)
| spindle wrote:
| It's not just the region of the sky with the most radio signals,
| it's the region of the sky with the signal that's (arguably) most
| likely to be produced by intelligence, of the ones we've noticed
| so far - the "WOW!" signal.
| abemiller wrote:
| Yea this title is not on the mark. it's not a region with the
| "most" radio signals at all. The concern of the paper is only
| about the Wow! signal.
| bewalt wrote:
| It was tough to keep the title accurate since I had to change
| it with the character limit. Thanks for clarifying for
| everyone!
| pvg wrote:
| The original title _An approximation to determine the
| source of the WOW! Signal_ seems to fit the limit just
| fine.
| callamdelaney wrote:
| We are definitely not alone. The great filter, in my opinion,
| does not exist. It's only the vastness of space and the
| relatively short time a civilization produces radio signals that
| makes it appear this way.
| nine_k wrote:
| Any civilization that realizes that they are not alone quickly
| stops bleeding RF signals to outer space, or at least learns to
| mask them as natural.
|
| Chances that two civilizations, if they detect each other,
| would be on the same level of development are slim. And once a
| less technologically advanced civilization meets a more
| technologically advanced one, game is over soon. Ask Aztecs, or
| Sioux, or pick any other historical example.
| bpodgursky wrote:
| That's a pretty shallow view of the Great Filter.
|
| Your implicit assumption is that not a single other intelligent
| species decided to harness the universe by, for example,
| consuming stars for their raw matter, or building Dyson spheres
| to black out entire sections of the sky.
|
| It is imo on you to explain why there's a hard cap on the
| exponential growth of intelligent life that prevents it from
| EVER reorganizing the universe in its own image. Not 99% of the
| time -- that's not enough for these purposes.
| Ekaros wrote:
| The truth might be than physics are harsh mistress and there
| is no way to cheat. Thus actually working extra system space
| colonization is just not something that we or anyone else can
| do. Maybe even technology to do stellar engineering is out of
| reach.
| kevin_thibedeau wrote:
| Space colonization is best done by robotic ships. These
| could very well be plying the galaxy and just staying away
| from primitive life.
| jhgb wrote:
| You should still be able to see them, even from distance,
| if they have any reasonable power output. Stealth doesn't
| really work in space.
| zabzonk wrote:
| > Space colonization is best done by robotic ships.
|
| But why do it? If you send a robot to (say) Alpha
| Centauri what have you actually acheived, at probably
| enormous cost?
| bpodgursky wrote:
| Ok, but to be clear, this is an argument that there IS a
| "Great Filter". It's just a Great Filter that is in front
| of us rather than behind us.
| SemanticStrengh wrote:
| no this is a filter to technological progress/expansion,
| not a filter to life appearance and sustainability in the
| universe..
| Jach wrote:
| It seems some people in this thread need a reminder of
| what the Great Filter is:
| https://mason.gmu.edu/~rhanson/greatfilter.html
| elorant wrote:
| The Great Filter can be a myriad of things. From how improbable
| life is to the hostility of the Universe. A magnetar has a
| hiccup and it sterilizes everything in a fifty light year
| radius. There are a shit ton of things out there that could
| eradicate life.
| danlugo92 wrote:
| Wikipedia says closest magnetar is 50k light years from
| earth...
| cosmiccatnap wrote:
| Sadly 1800 light years away means transmission to 2MASS
| 19281982-2640123 is impractical at best but observing it more to
| determine if other techno signals originate is a worthwhile
| endeavor.
|
| The ghosts of a distant civilization may still hold clues and
| even the knowledge that 1800 years ago we were potentially not
| alone is still an existential epiphany we are all hoping for.
| stephbu wrote:
| Maybe in 1,700yrs they'll see us...
| vinni2 wrote:
| 1800 years is a not that long in the cosmic scale.
| lostmsu wrote:
| 3600 years later: sorry, your bug report was closed due to
| inactivity.
| teekert wrote:
| 3600 for a return message. But think about what we looked
| like 1800 years ago and what will we look like in 1800 years?
| Will we still use radio even?
| Ekaros wrote:
| I would guess that if we are technologically advanced
| species we will. Though there is really question could we
| discern those signals. Probably there would be push to
| maximise the usage of available spectrum and then minimize
| use of power and probably even look into massive mimo.
| bdamm wrote:
| Or would we have transitioned to highly directed laser
| pulses, or perhaps using a medium not yet discovered?
| Since we are still fumbling in the dark about fundamental
| physics, having no grand unifying theory between large
| and small, or even much progress in understanding
| gravity, it is entirely possible that we wouldn't be
| using radio because we found something much better.
| mhh__ wrote:
| Other than as an inception agreement for a cult (has someone
| already written that book, other than L Ron Hubbard) 1800
| years is unfortunately a very long time in the scale of any
| human project.
| UnpossibleJim wrote:
| I guess it would depend on the ship... Though I am reading
| Rendezvous With Rama right now (my first time), which has
| completely changed my imagining of space ships. So much of
| sci-fi owes so much to Artur C. Clarke. I knew, but I
| didn't realize until I read more and more =/
| TedDoesntTalk wrote:
| > guess it would depend on the ship
|
| After 72 generations on a ship, it's possible the
| occupants won't even know they are on a ship
| (fictionalized by Brian Aldiss in the excellent book
| "Non-Stop").
|
| And if they know they're on a ship, they probably won't
| care to leave. After all, it is home and will have been
| for ages.
| evo_9 wrote:
| Reading the Abstract I can't help but wonder if their scientists
| discovered the same thing about us and pointed their 'eyes' (or
| whatever!) this way. Fun to think about.
| beaned wrote:
| This part is intriguing to me:
|
| > In fact, if we analyse the history of (the few) radio signals
| that humanity have sent to several targets in the hope of
| contacting a civilization, none of those transmissions had a long
| duration or were repeatedly sent for a long time. [...] An
| extraterrestrial civilization could have opted to behave in a
| similar manner.
| jmyeet wrote:
| Not the first time I've said this but it's highly unlikely that
| we'll detect technological civilizations through radio emissions.
| We've had this kind of radio emission but it's incredibly brief
| so for Earth, you'd have to be listening for a few decades over
| the billions of years Earth has existed. That's incredibly
| unlikely.
|
| The far more likely detection method is IR signatures,
| specifically from Dyson Swarms. A Dyson Swarm is not a rigid
| sphere (a confusion caused in part by the original name "Dyson
| Sphere"). It is a collection of orbitals with the intent of
| making full use of a star's energy output. The beauty of this is
| it's all rather low-tech needing little more than solar power,
| stainless steel level materials science and (this is the big one
| but is an engineering problem not a science one) getting access
| to basic raw materials.
|
| Just like a cloud looks solid despite being water droplets, a
| complete Dyson Swarm would be the same. The visible light would
| be blocked out.
|
| But here's where the IR part comes in. The only way to dissipate
| heat in space is to radiate it away. A habitat will have to do
| this. At any reasonable temperature the signature of that
| radiated heat is as IR radiation determined by the temperature of
| the radiating object. That's physics.
|
| So what's more likely: 1. Detecting a few decades of radio
| emissions or 2. the IR signature of what would likely be millions
| of years?
|
| So I applaud any investigation into the wow! signal just like I
| do of FRBs. We should understand likely causes but technological
| life? It almost certainly isn't.
| slimsag wrote:
| No stake in this game, but your likeliness assumption depends
| on the idea that a civilization _could_ get to the point of
| creating a Dyson Swarm. If civilizations are statistically
| likely to destroy themselves before then, 'detecting a few
| decades of radio emissions' could be the only scenario.
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(page generated 2022-05-06 23:00 UTC)