coderage9100 Posted November 16, 2018 Posted November 16, 2018 (edited) Hello! So, I've been listening to a lot of talks about alien life and the Fermi Paradox. It made me think; space is very very big. Is it just possible that the size of the galaxy is so vast that we just haven't had enough time to see any intelligent life? The galaxy is almost 53,000 light years across. That's quite a distance. Assuming Aplha Centauri isn't populated by space faring life, considering we see it 4 ish years in the past. Is that a valid argument? Thanks for your time! EDIT: I posted this twice by accident! My apologies. Edited November 16, 2018 by coderage9100 Got a post error, didn't realize it posted.
studiot Posted November 16, 2018 Posted November 16, 2018 7 minutes ago, coderage9100 said: Hello! So, I've been listening to a lot of talks about alien life and the Fermi Paradox. It made me think; space is very very big. Is it just possible that the size of the galaxy is so vast that we just haven't had enough time to see any intelligent life? The galaxy is almost 53,000 light years across. That's quite a distance. Assuming Aplha Centauri isn't populated by space faring life, considering we see it 4 ish years in the past. Is that a valid argument? Thanks for your time! EDIT: I posted this twice by accident! My apologies. Yes this is a respectable argument. It is generally offered in terms of the current best estimate of the age of the universe (about 14 billion years) and how long it has taken for humans to develop to the point of asking this question (less than a million years). So many civilisations could have come and gone in that time. 1
beecee Posted November 16, 2018 Posted November 16, 2018 (edited) 2 hours ago, coderage9100 said: Hello! So, I've been listening to a lot of talks about alien life and the Fermi Paradox. It made me think; space is very very big. Is it just possible that the size of the galaxy is so vast that we just haven't had enough time to see any intelligent life? The galaxy is almost 53,000 light years across. That's quite a distance. Assuming Aplha Centauri isn't populated by space faring life, considering we see it 4 ish years in the past. Is that a valid argument? Thanks for your time! EDIT: I posted this twice by accident! My apologies. I don't find the Fermi paradox inference valid at all. Time and distance are the two great inhibitors between interstellar/galactic contact. And of course it was constructed well before any extra solar planets were ever contemplated or found. The "near infinite" size of the universe, the "near infinite" content, the stuff of life being everywhere we look, suggests that we should not be the only planet with life in the universe. But irrespective, the facts at this time are that we have as yet no evidence for any life off this Earth. Edited November 16, 2018 by beecee
coderage9100 Posted November 16, 2018 Author Posted November 16, 2018 2 minutes ago, beecee said: I don't find the Fermi paradox inference valid at all. Time and distance are the two great inhibitors between interstellar/galactic contact. And of course it was constructed well before any extra solar planets were ever contemplated or found. The "near infinite" size of the universe, the "near infinite" content, the stuff of life being everywhere we look, suggests that we should not be the only planet with life in the universe. But irrespective, the facts at this time are that we have as yet no evidence for any life off this Earth. Right. And even if we are the first, which seems unlikely since on multiple occasions life almost didn't happen, not the mention the age of our planet, we almost certainly aren't the only. And while we got "lucky" things happened a few times that set us back again. So odds are those setbacks didn't happen on other planets. I just think distance and size of the galaxy makes it very very difficult to find signs of interplanetary/galactic societies. Not to mention the sheer amount of resources that would take. Makes more sense to just extend our lives and shrink the need for all those resources. The amount of effort needed to put forth to get resources so we can build something to get resources, just doesn't seem logical compared to the alternatives. Chances are they are out there but find better ways to deal with the resources crises. At least in my feeble human brain that makes the most sense.
beecee Posted November 16, 2018 Posted November 16, 2018 (edited) Let me say at this time, if, and that is a gigantic if, if we did somehow find out or had evidence to conclude we on Earth, were the only life forms in the universe, it would certainly raise far many more questions than the more obvious answer that we probably are not alone. The god botherers would have a field day! Edited November 16, 2018 by beecee
taeto Posted November 16, 2018 Posted November 16, 2018 Look, notice how every time we discover a prehistoric fossil, we always tend to ask why that organism happened to develop its long neck, or its ability for flight, its huge size, massive fangs, or any other anatomical features. Usually the answer goes along the lines of saying that it just happened to be that adaptation which made its survival and procreation within its current environment most likely. Compare with a species trying to advance by transmitting radio waves and laser beams out into space, or listening for same from remote sources. What is that going to do? As a method for evolutionary progress it seems totally doomed. No advanced extraterrestrial life form would survive for long by using such a survival strategy. Surely they are just like trilobites, happily feeding along the bottom of their respective oceans.
Heisenberg1927 Posted December 22, 2018 Posted December 22, 2018 On the contrary, if another planet existed (by chance alone) far away from Earth(like billion light years) which had an intelligent species such as ours (at least that's what we call ourselves)...we would come to know about them after a billion years(assuming they tried to make contact)...which is too long.
MigL Posted December 22, 2018 Posted December 22, 2018 Absolutely right. Civilizations may come and go in the time it takes for a signal to reach another civilization. Consider that a relatively nearby star like Epsilon Fornacis, at almost 100 LY distance, if it had intelligently inhabited planets, would only be receiving our earliest EM broadcasts from early in the past century; and any reply they might send our way would be received early in the 22nd century. Is there a chance we may not be here to receive the reply ? Now imagine a star 1000 or 10000 LY distant. What are the chances of us still being able to receive an EM signal ? ( think about where we were 10000 yrs ago )
J.C.MacSwell Posted December 22, 2018 Posted December 22, 2018 Maybe we are receiving multitudes of signals but simply haven't advanced to the point of recognizing them yet. Or maybe as any civilization advances to the point of sending coherent signals...they advance to the point of doing themselves in.
The Shadow Posted July 10, 2019 Posted July 10, 2019 (edited) I have lost track of current star estimates. I believe they keep increasing. Milky Way estimated at 400 billion? Galaxies estimated at 2 trillion (observable universe)? The enormous quantities sure imply, to me anyway, that we are not alone. Elapaed time sure does shake things up. As hinted at, in this thread, the chance of overlapping simultaneously appears remote. So many could have come and gone...reference, "Great Filter". On another note. Space voids always fascinated me. Why so empty? Possible advanced civilization harvesting stars via antimatter? Such things I ponder:( Edited July 10, 2019 by The Shadow 1
beecee Posted July 10, 2019 Posted July 10, 2019 8 hours ago, The Shadow said: pace voids always fascinated me. Why so empty? Possible advanced civilization harvesting stars via antimatter? Such things I ponder:( Isn't this at least partly due to DE? What I'm saying is that the gravity from the denser regions of space, are acting to pull galaxies together, and so making the voids larger due to the effects of the expansion over larger scales.
Airbrush Posted July 11, 2019 Posted July 11, 2019 11 hours ago, The Shadow said: I have lost track of current star estimates. I believe they keep increasing. Milky Way estimated at 400 billion? Galaxies estimated at 2 trillion (observable universe)?.. Who cares about intelligent life in another galaxy? I'm only interested in something nearby, like what is within our reach? How many habitable planets are within a radius of about 100 LY or even 1000 LY?
Sensei Posted July 11, 2019 Posted July 11, 2019 (edited) On 12/22/2018 at 9:18 PM, J.C.MacSwell said: Maybe we are receiving multitudes of signals but simply haven't advanced to the point of recognizing them yet. ...signals sent by humans at the moment are e.g. H.264/MPEG-4 AVC, highly compressed data.. How many people on this planet (not to mention extraterrestrial planets) know how to decode MPEG4.. ? Couple important bits missing during transmission, and you won't be able to decode/reverse engineer it.. ...if there would be global collapse of cooperation between countries, collapse of global trade.. currently existing computers would stop working in couple or couple dozen of years (natural damage of hardware).. Almost nobody knows how to make them. Almost nobody knows how to fix them. Almost nobody knows how to program them. Currently living humans can't even read their own computer and video tapes from '80 and '90 years. Computers and devices which could read them are gone. Any data stored on them are practically useless. But there was no global collapse. Just natural evolution of hardware. Hardware able to read old tapes was thrown to trashcans. New hardware replaced them. Try somebody read VHS and you will have headache. Without device able to read data or receive data, even humans are unable to read human-made data. They're practically indistinguishable from random noise. Edited July 11, 2019 by Sensei
dimreepr Posted July 11, 2019 Posted July 11, 2019 21 minutes ago, Sensei said: ...signals sent by humans at the moment are e.g. H.264/MPEG-4 AVC, highly compressed data.. How many people on this planet (not to mention extraterrestrial planets) know how to decode MPEG4.. ? Couple important bits missing during transmission, and you won't be able to decode/reverse engineer it.. Not to mention the signal wouldn't be decipherable, even if they could decode/reverse engineer it.
Strange Posted July 11, 2019 Posted July 11, 2019 7 hours ago, Sensei said: ..signals sent by humans at the moment are e.g. H.264/MPEG-4 AVC, highly compressed data.. How many people on this planet (not to mention extraterrestrial planets) know how to decode MPEG4.. ? Couple important bits missing during transmission, and you won't be able to decode/reverse engineer it.. Also the use of spread spectrum techniques mean that signals are virtually indistinguishable from noise (and lower power transmission is needed) so it might not even be recognised as a signal if it were detected.
Moontanman Posted July 11, 2019 Posted July 11, 2019 On 11/16/2018 at 11:49 AM, coderage9100 said: Hello! So, I've been listening to a lot of talks about alien life and the Fermi Paradox. It made me think; space is very very big. Is it just possible that the size of the galaxy is so vast that we just haven't had enough time to see any intelligent life? The galaxy is almost 53,000 light years across. That's quite a distance. Assuming Aplha Centauri isn't populated by space faring life, considering we see it 4 ish years in the past. Is that a valid argument? Thanks for your time! EDIT: I posted this twice by accident! My apologies. Our galaxy is 150,000 lys plus across but size is not a valid argument, technology could eventually conquer the entire local cluster of galaxies given a few hundred million years. On 11/16/2018 at 2:07 PM, beecee said: But irrespective, the facts at this time are that we have as yet no evidence for any life off this Earth. You seem to be using the word evidence in place of the word proof, no proof but a body if evidence does indeed exist from the first mars landing to the universe being filled with organics. On 11/16/2018 at 2:19 PM, coderage9100 said: Right. And even if we are the first, which seems unlikely since on multiple occasions life almost didn't happen, not the mention the age of our planet, we almost certainly aren't the only. And while we got "lucky" things happened a few times that set us back again. So odds are those setbacks didn't happen on other planets. I just think distance and size of the galaxy makes it very very difficult to find signs of interplanetary/galactic societies. Not to mention the sheer amount of resources that would take. Makes more sense to just extend our lives and shrink the need for all those resources. The amount of effort needed to put forth to get resources so we can build something to get resources, just doesn't seem logical compared to the alternatives. Chances are they are out there but find better ways to deal with the resources crises. At least in my feeble human brain that makes the most sense. Life uses resources, space is full of such resources, saying the effort to use them is greater than they would be worth is like saying digging iron to build cars makes it illogical to drive to a gas station to buy gas... On 11/16/2018 at 2:53 PM, beecee said: Let me say at this time, if, and that is a gigantic if, if we did somehow find out or had evidence to conclude we on Earth, were the only life forms in the universe, it would certainly raise far many more questions than the more obvious answer that we probably are not alone. The god botherers would have a field day! The only thing scarier than finding out we are not alone is finding out we are alone... paraphrasing A.C. Clark... On 11/16/2018 at 3:02 PM, taeto said: Look, notice how every time we discover a prehistoric fossil, we always tend to ask why that organism happened to develop its long neck, or its ability for flight, its huge size, massive fangs, or any other anatomical features. Usually the answer goes along the lines of saying that it just happened to be that adaptation which made its survival and procreation within its current environment most likely. Compare with a species trying to advance by transmitting radio waves and laser beams out into space, or listening for same from remote sources. What is that going to do? As a method for evolutionary progress it seems totally doomed. No advanced extraterrestrial life form would survive for long by using such a survival strategy. Surely they are just like trilobites, happily feeding along the bottom of their respective oceans. This makes no sense, sending out radio waves or lasers is so easy and cheap it could not impact our survival in any way and even if it did the sun is going to kill us in a few hundred million years if we don't move out into the galaxy... And BTW all the trilobites are dead, mostly because all they did was crawl along the bottom feeding on the mud... On 12/22/2018 at 1:04 PM, Heisenberg1927 said: On the contrary, if another planet existed (by chance alone) far away from Earth(like billion light years) which had an intelligent species such as ours (at least that's what we call ourselves)...we would come to know about them after a billion years(assuming they tried to make contact)...which is too long. We currently are aware of several thousand planets within around 1000 light years of the earth, at least one planet in the habitable zone around the nearest star. I am not sure why you would assert the idea that another earth would have to be a billion light years from Earth... On 12/22/2018 at 1:43 PM, MigL said: Absolutely right. Civilizations may come and go in the time it takes for a signal to reach another civilization. Consider that a relatively nearby star like Epsilon Fornacis, at almost 100 LY distance, if it had intelligently inhabited planets, would only be receiving our earliest EM broadcasts from early in the past century; and any reply they might send our way would be received early in the 22nd century. Is there a chance we may not be here to receive the reply ? Now imagine a star 1000 or 10000 LY distant. What are the chances of us still being able to receive an EM signal ? ( think about where we were 10000 yrs ago ) Our everyday radio emissions would not be detectable buy us at the distance of the nearest star. Intentional radio signals or military type radar would be but would not be repeatable and would therefore not be considered intelligent signals ny our own SETI program if we detected them. BTW we have detected such signals but since they didn't repeat... 12 hours ago, Airbrush said: Who cares about intelligent life in another galaxy? I'm only interested in something nearby, like what is within our reach? How many habitable planets are within a radius of about 100 LY or even 1000 LY? https://en.m.wikipedia.org/wiki/List_of_potentially_habitable_exoplanets Quote In November 2013, astronomers reported, based on Kepler space mission data, that there could be as many as 40 billion Earth-sized planetsorbiting in the habitable zones of Sun-like stars and red dwarfs in the Milky Way,[5][6] 11 billion of which may be orbiting Sun-like stars.[7] https://en.wikipedia.org/wiki/List_of_nearest_terrestrial_exoplanet_candidates Quote Exoplanets discovered (incomplete)[edit] This list is incomplete, currently containing 34 exoplanets, 11 of which probably lie inside their star's habitable zone. There are roughly 2,000 stars at a distance of up to 50 light-years from our Solar System[4] (64 of them are yellow-orange "G" stars like our Sun[5]). As many as 15% of them can have Earth-sized planets in the habitable zones.[6] On November 4, 2013, astronomers reported, based on Kepler space mission data, that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of sun-like stars and red dwarf stars within the Milky Way Galaxy.[7][8] 11 billion of these estimated planets may be orbiting sun-like stars.[9] The nearest such planet may be as close as 12 light-years away.[7][8] On August 24, 2016, astronomers announced the discovery of a rocky planet in the habitable zone of Proxima Centauri, the closest star to Earth (not counting the Sun). Called Proxima b, the planet is 1.3 times the mass of Earth and has an orbital period of roughly 11.2 Earth days.[10] However Proxima Centauri's classification as a red dwarf casts doubts on the habitability of any exoplanets in its orbit due to low stellar flux, high probability of tidal locking, small circumstellar habitable zones and high stellar variation. Another likely candidate is Alpha Centauri, Earth's nearest Sun-like star system 4.37 light years away. Estimates place the probability of finding a habitable planet around Alpha Centauri A or B at roughly 75%.[11] Alpha Centauri is the target of several exoplanet-finding missions, including Breakthrough Starshotand Mission Centaur, the latter of which is chronicled in the 2016 documentary film, "The Search for Earth Proxima."[12]
swansont Posted July 11, 2019 Posted July 11, 2019 51 minutes ago, Moontanman said: Our galaxy is 150,000 lys plus across but size is not a valid argument, technology could eventually conquer the entire local cluster of galaxies given a few hundred million years. That's not apparent to me. Arguments I've seen in support of this seem flawed.
Moontanman Posted July 11, 2019 Posted July 11, 2019 (edited) 8 minutes ago, swansont said: That's not apparent to me. Arguments I've seen in support of this seem flawed. The only current flaw I am aware of is our lack of controlled fusion. Can you point out a few more, I'd like to be less wrong if possible.. Edited July 11, 2019 by Moontanman
swansont Posted July 11, 2019 Posted July 11, 2019 1 minute ago, Moontanman said: The only current flaw I am aware of is our lack of controlled fusion. Can you point out a few more, I'd like to be less wrong if possible.. What is the longest any group of humans have lived in an isolated environment, as one might experience in space travel?
Moontanman Posted July 11, 2019 Posted July 11, 2019 1 minute ago, swansont said: What is the longest any group of humans have lived in an isolated environment, as one might experience in space travel? That is just technological development not a flaw. It's like saying the ISS defines how big a space habitat can be. Mckendree cylinders would solve the isolation aspect, it's just a matter of size.
swansont Posted July 11, 2019 Posted July 11, 2019 I've seen arguments that take a distance and argue that there is this very small speed that expansion requires, but the problem with that is it ignores the discrete nature of the travel. There is no place to stop and resupply in the middle of nowhere. It's not a matter of only going some speed. It's a matter of surviving until you get to the next habitable planet. You can argue it took 10,000 years to expand across the ocean to the new world, and that's 10,000 km (just for sake of argument), so the speed was just 1 km/year, but you don't just go 1 km out into the ocean that first year. At the very minimum you have to go to the next island. 1 minute ago, Moontanman said: That is just technological development not a flaw. Again, I'm not convinced this is true. It's just an assertion. Not an actual argument.
Moontanman Posted July 11, 2019 Posted July 11, 2019 Just now, swansont said: I've seen arguments that take a distance and argue that there is this very small speed that expansion requires, but the problem with that is it ignores the discrete nature of the travel. There is no place to stop and resupply in the middle of nowhere. It's not a matter of only going some speed. It's a matter of surviving until you get to the next habitable planet. You can argue it took 10,000 years to expand across the ocean to the new world, and that's 10,000 km (just for sake of argument), so the speed was just 1 km/year, but you don't just go 1 km out into the ocean that first year. At the very minimum you have to go to the next island. Recent discoveries show space is full of the material we need to build, refuel, top up volatiles, and simply live in the depths of space. Space dust can be collected without ever slowing down if nothing else. Speeds would be slow but since you travel in your own little world that becomes irrelevant.
swansont Posted July 11, 2019 Posted July 11, 2019 Just now, Moontanman said: Recent discoveries show space is full of the material we need to build, refuel, top up volatiles, and simply live in the depths of space. Space dust can be collected without ever slowing down if nothing else. Speeds would be slow but since you travel in your own little world that becomes irrelevant. Citation needed
Bufofrog Posted July 11, 2019 Posted July 11, 2019 1 minute ago, Moontanman said: Speeds would be slow but since you travel in your own little world that becomes irrelevant I really think you are minimizing the incredible difficulty in making your own little world that flies around space!
Moontanman Posted July 11, 2019 Posted July 11, 2019 (edited) 5 minutes ago, Bufofrog said: I really think you are minimizing the incredible difficulty in making your own little world that flies around space! I suggest you do some research... Your assertion still sounds like someone standing on an iron ore deposit and says it's impossible to use it to make cars... Edited July 11, 2019 by Moontanman
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