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Nearest Thinking Aliens Probably 'Right Next Door'
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In truth, this article over at NBC News says "the nearest aliens are probably between one and two-thousand light-years away," which really is 'right next door' if you think in terms of distance between stars and other objects in the galaxy and the larger universe, which is almost incomprehensibly vast. But there's always hope, right? :-)

Anyway, the reasoning behind the hypothesis that the nearest thinking aliens are actually pretty far away, at least by the way we measure distance in space and our (current) ability to traverse it, is pretty simple:

"Intelligence is less certain. The dinosaurs were a good design but didn't do well in school. But let's say that one in 100 biology-encrusted planets eventually coughs up some thinking beings. And, as per Frank Drake, let's also assume that any Klingons out there continue to hang out for 10,000 years before self-destructing (nuclear war, anyone?) or meeting some other woeful end.

Do the arithmetic, and you'll find that one in 100 million star systems has technically adept inhabitants. That's not much different than the fraction of jackpot tickets in this week's Powerball lottery.

So how close are the nearest signaling extraterrestrials? If we're going to pay good money to fire up the warp drive and visit some bumpy-headed aliens, how far do we have to travel? Well, the average distance between stars in our part of the galaxy is 4.2 light-years (the distance to Proxima Centauri). That is, for every cube of space that's 4.2 light-years on a side, you'll find (on average) one star. Now imagine a bigger box, 2,000 light-years on a side. It will contain 100 million star boxes, and one sophisticated civilization.

By this rough and ready calculation, the nearest aliens are probably between one and two thousand light-years away. In other words, no closer than the three bright stars of Orion's Belt. Sure, alien neighbors might be farther — or closer. But this order-of-magnitude estimate tells us that they're not next door. They haven't heard our news reports, and they're not likely to have any incentive to visit. They simply don't know we're here."

The article also notes that at the speed produced by our fastest rocket ships today it would take 20 million years to reach an intelligent alien society which likely exists about 2,000 light-years from Earth. Such a distance is simply too far away for us to travel to, given the limitations of our rocketry and plain old physics. Even if we were to invent a means of propulsion that matches the speed of light (something Einstein says is impossible to do), we'd still need 2,000 years of travel to reach our intelligent neighbors down the interstellar block, so to speak.

Add in that if the speed of light is the universal constant and something that simply cannot be exceeded in a conventional or linear fashion (and the possibility of traveling via wormholes, skirting the event horizons of black holes, or bending, folding or "warping" space is mostly science fiction at present), and we're kind of stuck. Even our earliest radio signals won't reach the nearest likely intelligent aliens for another 1900 years, give or take. Making things more maddening is the fact of math and it demonstrating there may be 10,000 intelligent societies in just our Milky Way galaxy alone. Unfortunately and unlike what the old commercial used to say about reaching out and touching someone, in this case it's much, much more difficult than it sounds.

Our nearest local star is 4.2 light-years, or over 24 TRILLION miles, away (at almost 6 trillion miles to the light-year). And that's right next door in terms of distance when looking at just our galaxy, let alone the universe and the 2 trillion galaxies within it. As it turns out, Earth is just a tiny dust particle plopped down into an Olympic-size swimming pool of water, with the next tiny dust particle way over on the other end of the pool, and that may not even be the true scale of the distances involved. Yeesh. ;-)

"Politics is just show business for ugly people."
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [big kahuna] [ In reply to ]
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If our universe is that big and space as vast as you describe how do we know it’s infinite ? Years ago we knew the Earth was flat. What if Abbot was really describing the universe and its not only flat but multidimensional !

"I think I've cracked the code. double letters are cheaters except for perfect squares (a, d, i, p and y). So Leddy isn't a cheater... "
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [Leddy] [ In reply to ]
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Years ago we knew the Earth was flat.
---

Umm, we've known the earth was round for well over 2000 years now.






Take a short break from ST and read my blog:
http://tri-banter.blogspot.com/
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [Leddy] [ In reply to ]
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Leddy wrote:
If our universe is that big and space as vast as you describe how do we know it’s infinite ? Years ago we knew the Earth was flat. What if Abbot was really describing the universe and its not only flat but multidimensional !

Science tells us that the universe -- that portion of space, or the void, that contains all the galaxies, stars, nebulae, gases, observable (and dark) matter and other materials -- is still expanding and that such expansion hasn't slowed down as yet, as it's been theorized it will do someday. Beyond the universe is the void, of which we know nothing, but can make educated guess as to its makeup (space without all the stuff crammed into the universe).

The universe itself had a beginning, at least in light of contemporary theories, and will have a (theorized) end. The void? It could be infinite, we think, in both time and space. At least, that's what we can comprehend about something that may be incomprehensible right now.

Multiverses may or may not exist. Recent postulating by some pretty smart folks says that they probably don't.

"Politics is just show business for ugly people."
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [big kahuna] [ In reply to ]
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Beyond the universe is the void, of which we know nothing, but can make educated guess as to its makeup (space without all the stuff crammed into the universe).

Incorrect weed hopper. You need to do some reading on this. The universe is not three dimensional. If you travelled in one direction you would eventually return to your starting point. There is no "outside" the universe. Here is one link. Google "what is the universe expanding into" or "what is outside the universe."

________
It doesn't really matter what Phil is saying, the music of his voice is the appropriate soundtrack for a bicycle race. HTupolev
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [big kahuna] [ In reply to ]
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Two thousand light years explains why aliens haven't heard us, but it doesn't explain why we haven't heard them.

Sure, there's a whole "means of communication" thing where we wouldn't be able to understand an advanced means of communication (or that they're even using one) - much like how bronze age people's wouldn't get how radio waves work.

But if the average spacing between intelligent species is 2k light years, you'd figure that someone within range of our sensors would be broadcasting (like we do with all our communication) in a method you could pick up. Even if our tech is millions of years older than the most advanced tech, we'd still be able to pick up the signals from those planets which are millions of light years away.

I think that the universe is likely teeming with life, but I'd wager that the 1 in 200 figure for developing advanced intelligent societies is likely low (as is the share of systems that likely harbour life).
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [H-] [ In reply to ]
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H- wrote:
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Beyond the universe is the void, of which we know nothing, but can make educated guess as to its makeup (space without all the stuff crammed into the universe).


Incorrect weed hopper. You need to do some reading on this. The universe is not three dimensional. If you travelled in one direction you would eventually return to your starting point. There is no "outside" the universe. Here is one link. Google "what is the universe expanding into" or "what is outside the universe."

That's just another supposition, though an educated one (as is the one about the void), I'll grant. Grasshopper. ;-)

"Politics is just show business for ugly people."
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [timbasile] [ In reply to ]
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timbasile wrote:
Two thousand light years explains why aliens haven't heard us, but it doesn't explain why we haven't heard them.

Sure, there's a whole "means of communication" thing where we wouldn't be able to understand an advanced means of communication (or that they're even using one) - much like how bronze age people's wouldn't get how radio waves work.

But if the average spacing between intelligent species is 2k light years, you'd figure that someone within range of our sensors would be broadcasting (like we do with all our communication) in a method you could pick up. Even if our tech is millions of years older than the most advanced tech, we'd still be able to pick up the signals from those planets which are millions of light years away.

I think that the universe is likely teeming with life, but I'd wager that the 1 in 200 figure for developing advanced intelligent societies is likely low (as is the share of systems that likely harbour life).

Even if we do pick up signals from an intelligent species, what do we do then? We're just too far away to reach them, given our current technology and the limits of physics postulated by Einstein. Such a civilization, if it was far advanced from ours, would have to be reaching out via signals and including data on how to use their technology to reach them (always supposing they're not the UFO-using species that some of the more fevered folks among us insist are watching us even now ;-).

The other side of that coin is, maybe the universe isn't as friendly as we're assuming and other advanced civilizations may be hiding for fear of giving up their locations to known hostile civilizations (granted, that's more science fiction-y -- a la David Brin and his Uplift Saga series, but it could happen). Of course, if they're that advanced, we wouldn't be able to stop them doing whatever it is they'd want to do to us, so I think we'd better be ready to welcome our alien overlords when they arrive. LOL!

"Politics is just show business for ugly people."
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [Tri-Banter] [ In reply to ]
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Tri-Banter wrote:
Years ago we knew the Earth was flat.
---

Umm, we've known the earth was round for well over 2000 years now.

Right years ago, not last year.

Centuries ago , better ?

"I think I've cracked the code. double letters are cheaters except for perfect squares (a, d, i, p and y). So Leddy isn't a cheater... "
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [big kahuna] [ In reply to ]
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I don't think could do anything meaningful. We could figure out a universal way to say hi - perhaps a repeating signal in binary could work - but we've been sending out radio waves, tv transmissions, etc for many years so they'd likely get that first and would be able to pick that up.

Even if all the other civilizations are hiding from a super predator species, there'd be a time period between learning how to transmit and learning how to hide your transmissions. Under this hypothesis, we're in that period now. Even if we figure out why and how we should hide our communications transmissions tomorrow, there's a 100 years of broadcasting which advertises our presence to outsiders. (The article says 10,000 years before self-destructing)

The way I figure, even if each intelligent civilization broadcasts for 100 years, you're still going to wind up with billions of advanced societies who have this sort of window where they broadcast using some tech we can pick up. Then you now have a transmission window for each star, which aligns with the distance from us to that star where we'd pick up that 100 year open transmission. So for each star system, our transmission window is (distance to star) +/- 50 years.

That's still millions of stars and likely thousands of civilizations.
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [timbasile] [ In reply to ]
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timbasile wrote:
I don't think could do anything meaningful. We could figure out a universal way to say hi - perhaps a repeating signal in binary could work - but we've been sending out radio waves, tv transmissions, etc for many years so they'd likely get that first and would be able to pick that up.

Even if all the other civilizations are hiding from a super predator species, there'd be a time period between learning how to transmit and learning how to hide your transmissions. Under this hypothesis, we're in that period now. Even if we figure out why and how we should hide our communications transmissions tomorrow, there's a 100 years of broadcasting which advertises our presence to outsiders. (The article says 10,000 years before self-destructing)

The way I figure, even if each intelligent civilization broadcasts for 100 years, you're still going to wind up with billions of advanced societies who have this sort of window where they broadcast using some tech we can pick up. Then you now have a transmission window for each star, which aligns with the distance from us to that star where we'd pick up that 100 year open transmission. So for each star system, our transmission window is (distance to star) +/- 50 years.

That's still millions of stars and likely thousands of civilizations.


This is a really interesting topic.

Your logic came up in this thread (also started by BK) a while ago. I believe that the line of thought that leads to a very small chance of contacting aliens hinges on the premise that civilizations that become advanced enough to communicate on a galactic scale become extinct in 100, 1000, or 10,000 years, creating a very small window of potential contact.

Working within that premise, your math seems a bit off, and the "billions of advanced societies who have this sort of window" are not numerous enough given the other large numbers involved to create a good chance of contact.

However, I question the underlying premise of technologically advanced civilizations inevitably going extinct "soon" after reaching a level of technology that allows their detection/communication. The cynic in me believes that may likely be the case, but there doesn't seem to be much if any evidence to support the premise. Even if individual civilizations do, in fact, go extinct on a 100-10,000 year time frame, that doesn't imply that entire planets do. Even on earth, one may believe that humans are on their last leg. But who is to say if some post-human civilization will replace us -- artificial intelligence, hive-intelligent insects, etc. -- that would greatly extend the time that earth is capable of interstellar detection/communication?


"100% of the people who confuse correlation and causation end up dying."
Last edited by: MOP_Mike: Jan 28, 18 9:43
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [MOP_Mike] [ In reply to ]
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leads to a very small chance of contacting aliens hinges on the premise that civilizations that become advanced enough to communicate on a galactic scale become extinct in 100, 1000, or 10,000 years, creating a very small window of potential contact. //

This is most likely the right answer. We can calculate a probability of sentient life evolving in the universe, but you also have to lay that over their extinction or evolution into something we would never recognize. So even if you give a million years for a civilization to survive while communicating, the odds that it overlaps with us is quite diminished by time. Since the universe is about 14 billion years old, so lets say it took a couple billion for the cycle of life to begin, that is a lot of time for all those civilizations to come and go. If the 10k or even 100k years number for species survival is closer, then it is improbable that we would ever overlap with someone even remotely in our neighborhood.


But perhaps one day we will pick up on a long gone message from some far reaches of other galaxy's, our gold record is just beginning its journey and no doubt in millions of years someone may pick up on it, as long as space dust doesn't destroy it in the meantime..
Last edited by: monty: Jan 28, 18 11:50
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [timbasile] [ In reply to ]
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timbasile wrote:
I think that the universe is likely teeming with life, but I'd wager that the 1 in 200 figure for developing advanced intelligent societies is likely low (as is the share of systems that likely harbour life).

I think it is high. In 4.5 billion years of evolution on earth, there's been exactly one species evolve advanced intelligent, doesn't appear any other lineage has even taken baby steps in that direction. And many of our ancestors or close cousins that did take those baby steps still went extinct, and it appears it took us roughly 200k years once we evolved advanced intelligent to get to the point where we are today.

Seems like from what we know of life on earth, advanced intelligence is extremely unlikely to evolve.
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [big kahuna] [ In reply to ]
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big kahuna wrote:
timbasile wrote:
Two thousand light years explains why aliens haven't heard us, but it doesn't explain why we haven't heard them.

Sure, there's a whole "means of communication" thing where we wouldn't be able to understand an advanced means of communication (or that they're even using one) - much like how bronze age people's wouldn't get how radio waves work.

But if the average spacing between intelligent species is 2k light years, you'd figure that someone within range of our sensors would be broadcasting (like we do with all our communication) in a method you could pick up. Even if our tech is millions of years older than the most advanced tech, we'd still be able to pick up the signals from those planets which are millions of light years away.

I think that the universe is likely teeming with life, but I'd wager that the 1 in 200 figure for developing advanced intelligent societies is likely low (as is the share of systems that likely harbour life).


Even if we do pick up signals from an intelligent species, what do we do then? We're just too far away to reach them, given our current technology and the limits of physics postulated by Einstein. Such a civilization, if it was far advanced from ours, would have to be reaching out via signals and including data on how to use their technology to reach them (always supposing they're not the UFO-using species that some of the more fevered folks among us insist are watching us even now ;-).

The other side of that coin is, maybe the universe isn't as friendly as we're assuming and other advanced civilizations may be hiding for fear of giving up their locations to known hostile civilizations (granted, that's more science fiction-y -- a la David Brin and his Uplift Saga series, but it could happen). Of course, if they're that advanced, we wouldn't be able to stop them doing whatever it is they'd want to do to us, so I think we'd better be ready to welcome our alien overlords when they arrive. LOL!

We don't want to meet any aliens. If they can travel here in a reasonable amount of time they can harness energy in a way that we cannot imagine and that we would be powerless against.

We have seen how this plays out. We would not be equals. How do humans treat critters they are obviously superior to?

It would look more like this:


I'm beginning to think that we are much more fucked than I thought.
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [big kahuna] [ In reply to ]
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big kahuna wrote:
The other side of that coin is, maybe the universe isn't as friendly as we're assuming and other advanced civilizations may be hiding for fear of giving up their locations to known hostile civilizations (granted, that's more science fiction-y -- a la David Brin and his Uplift Saga series, but it could happen). Of course, if they're that advanced, we wouldn't be able to stop them doing whatever it is they'd want to do to us, so I think we'd better be ready to welcome our alien overlords when they arrive. LOL!

Funny that you mentioned the Uplift Saga, just started rereading this.


Jim

**Note above poster works for a retailer selling bikes and related gear*
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [j p o] [ In reply to ]
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j p o wrote:

We don't want to meet any aliens. If they can travel here in a reasonable amount of time they can harness energy in a way that we cannot imagine and that we would be powerless against.

We have seen how this plays out. We would not be equals. How do humans treat critters they are obviously superior to?

It would look more like this:



"What's your claim?" - Ben Gravy
"Your best work is the work you're excited about" - Rick Rubin
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [j p o] [ In reply to ]
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j p o wrote:
big kahuna wrote:
timbasile wrote:
Two thousand light years explains why aliens haven't heard us, but it doesn't explain why we haven't heard them.

Sure, there's a whole "means of communication" thing where we wouldn't be able to understand an advanced means of communication (or that they're even using one) - much like how bronze age people's wouldn't get how radio waves work.

But if the average spacing between intelligent species is 2k light years, you'd figure that someone within range of our sensors would be broadcasting (like we do with all our communication) in a method you could pick up. Even if our tech is millions of years older than the most advanced tech, we'd still be able to pick up the signals from those planets which are millions of light years away.

I think that the universe is likely teeming with life, but I'd wager that the 1 in 200 figure for developing advanced intelligent societies is likely low (as is the share of systems that likely harbour life).


Even if we do pick up signals from an intelligent species, what do we do then? We're just too far away to reach them, given our current technology and the limits of physics postulated by Einstein. Such a civilization, if it was far advanced from ours, would have to be reaching out via signals and including data on how to use their technology to reach them (always supposing they're not the UFO-using species that some of the more fevered folks among us insist are watching us even now ;-).

The other side of that coin is, maybe the universe isn't as friendly as we're assuming and other advanced civilizations may be hiding for fear of giving up their locations to known hostile civilizations (granted, that's more science fiction-y -- a la David Brin and his Uplift Saga series, but it could happen). Of course, if they're that advanced, we wouldn't be able to stop them doing whatever it is they'd want to do to us, so I think we'd better be ready to welcome our alien overlords when they arrive. LOL!

We don't want to meet any aliens. If they can travel here in a reasonable amount of time they can harness energy in a way that we cannot imagine and that we would be powerless against.

We have seen how this plays out. We would not be equals. How do humans treat critters they are obviously superior to?

It would look more like this:

We’ve seen what humans do that doesn’t really mean much for that advanced of a race or different race. I agree that if they want to destroy us it wouldn’t even be a challenge. With the power they would be harnessing they could probably destroy the earth Death Star style without trying.

But that also assumes that killing of others is normal across the universe. Since we have no proof that’s the case it’s impossible to know how they would interact. For all we know we could be the oddballs and other races don’t even understand the concept of killing their own species.

I subscribe more to the thought of if they are out there watching us or have watched us they just have no desire to interact with us. It’d be like you going out of your way to have a conversation with an squirrel. There’s just no point.
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [Grant.Reuter] [ In reply to ]
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I tend to subscribe to the "Dark Forest" school of thought on this subject. It's based on two proposed axioms.

1. The primary goal of any civilization is survival.
2. Civilizations need to expand to continue to survive, and there are finite resources to do so.

Essentially every civilization is living in a dark forest. It is either hunting other civilizations for resources to expand and survive, or it is hiding from the hunters, trying to survive without being destroyed for it's own resources.

If a civilization finds another, it has some choices. Reach out and make friends, avoid and leave alone, or destroy to remove threats and/or take resources.

If Civilization A finds B, and contacts it to make friends, there is the chance that B is more powerful, or more xenophobic, or might misinterpret A's overtures, and destroy A. A might think they are powerful enough to defend themselves against what they think is B's strength, but over the time it takes to communicate, B could experience a technological leap that would put them on par or surpassing A, making them a threat. If A decides not to risk anything and just leave B alone, they're actually risking B becoming more powerful, finding A, and destroying A. So A's safest choice is to destroy B as quickly as possible. Any other option risks B finding, surpassing, and destroying A.

And if the two civilizations do find each other and communicate, aside from time lag, different methods of communication, etc, there is a chain of suspicion that should lead each to find it necessary to destroy the other. A suspects B can/wants to destroy A, so A wants to destroy B. B suspects that A suspects B and wants to destroy B, so B wants to destroy A. And so on, and so on....

So basically, civilizations should attempt to remain hidden as long as possible, but if they find or are found by another civilization, they should immediately destroy it to ensure survival and/or take resources to assist in expansion and survival.

Slowguy

(insert pithy phrase here...)
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [slowguy] [ In reply to ]
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The good news with that is if they can move about the galaxy there are plenty of planets and moons with resources to go to. You don't have to seek out ones with critters. Plenty of water in comets and moons, methane everywhere, hydrogen everywhere, metals all over the place.

What these places don't have are nice beaches. So we need to be careful if they show up in their bathing suits.

I'm beginning to think that we are much more fucked than I thought.
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [Jim] [ In reply to ]
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Jim wrote:
big kahuna wrote:

The other side of that coin is, maybe the universe isn't as friendly as we're assuming and other advanced civilizations may be hiding for fear of giving up their locations to known hostile civilizations (granted, that's more science fiction-y -- a la David Brin and his Uplift Saga series, but it could happen). Of course, if they're that advanced, we wouldn't be able to stop them doing whatever it is they'd want to do to us, so I think we'd better be ready to welcome our alien overlords when they arrive. LOL!


Funny that you mentioned the Uplift Saga, just started rereading this.

I first read the initial book in the saga, Sundiver, back in 1981 when I was out on a deployment. Been enjoying those Uplift books ever since and reread them every once in awhile. :-)

"Politics is just show business for ugly people."
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Re: Nearest Thinking Aliens Probably 'Right Next Door' [j p o] [ In reply to ]
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j p o wrote:
The good news with that is if they can move about the galaxy there are plenty of planets and moons with resources to go to. You don't have to seek out ones with critters. Plenty of water in comets and moons, methane everywhere, hydrogen everywhere, metals all over the place.

What these places don't have are nice beaches. So we need to be careful if they show up in their bathing suits.

I like the way you think. :-)

Anyway; from what I understand, every exoplanet that we've so far managed to examine (even with our rudimentary ability to do so) has turned out to be completely inhospitable to life, at least as we can imagine "life," from our frame of reference. Either they're massive gas giants, or they're rocky planets with hellish atmospheres that are located too close to their stars. So if other intelligent races have evolved out there, in the kind of planetary conditions that may be all too common, maybe they're looking for planets to exploit that feature those sorts of conditions, like for the kinds of gases, minerals and chemicals that would be abundant on such planets and other celestial bodies?

I know there was a lot of hype surrounding the Gliese 581 planetary system, in terms of potential habitability for us, but off the top of my head I think the three planets that were supposedly good candidates for life were kind of big, from a mass standpoint (meaning high gravity... minimum 5 times that of Earth) and not hospitable to us or most other oxygen-breathing species on Earth.

"Politics is just show business for ugly people."
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