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Study: No evidence of advanced alien life in nearby galaxies
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River Song Send message Joined: 30 Jul 15 Posts: 268 Credit: 1,735,966 RAC: 0 |
Study: No evidence of advanced alien life in nearby galaxies Fox News 9/24/15 3:43 PM PDST While a sequel to the 1990s alien invasion flick "Independence Day" is in the works, moviegoers shouldn't worry about fact following fiction anytime soon. This is according to [a new report](http://arxiv.org/pdf/1508.02624v1.pdf) by the Netherlands Institute for Radio Astronomy, which determined that there are no signs of advanced alien life in 93 of our neighboring galaxies. Does ET know this? River Song (aka Linda Latte on planet Earth) "Happy I-Phone girl on the GO GO GO" |
KLiK Send message Joined: 31 Mar 14 Posts: 1304 Credit: 22,994,597 RAC: 60 |
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William Rothamel Send message Joined: 25 Oct 06 Posts: 3756 Credit: 1,999,735 RAC: 4 |
I am too ignorant to vouch for their thinking, accuracy and methods. My take-away is that there are no Dyson Sphere's out there. I probably could have told you that with a high level of confidence. I think that we will have enough problems just trying to find truly habitable planets out to 100 to 1000 light years. If we find some then we could focus our listening there--but probably only for a high-powered beacon. Even then there may be not a single such planet found. All very speculative --but that's the nature of the uncertainty in this endeavor. Opinions matter little--facts are the key. At some points facts or the lack of them should lead to logical conclusions that are sound. |
John D Anthony Send message Joined: 4 Sep 15 Posts: 177 Credit: 1,303,001 RAC: 1 |
This is a different study than the one discussed in another thread but I draw the same conclusion - it's absurd. With the technology we have you could study Andromeda, right next door, for a hundred years and still not be able to confirm anything about alien civilizations. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1384 Credit: 2,098,506 RAC: 5 |
An astronomical search for Dyson spheres seems a worthwhile endeavor, given our lack of knowledge about the technology of advanced stellar civilizations. Having said that, we should also realize that from our very limited perspective, predictions of what forms more advanced technologies will take are questionable, at best. For all we know, Dyson spheres may be regarded as merely a quaint notion, by extraterrestrials with access to some better means of obtaining energy. Further, any form of waste heat produced by whatever technologies are actually in use may have be reduced to the point that we simply can't detect it. |
Bob DeWoody Send message Joined: 9 May 10 Posts: 3387 Credit: 4,182,900 RAC: 10 |
According to science fiction science Dyson spheres couldn't be detected until accidentally stumbled upon. I wonder how a structure that totally encases a star to capture the energy of said star to power a civilization could ever be detected from another galaxy. Bob DeWoody My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events. |
John D Anthony Send message Joined: 4 Sep 15 Posts: 177 Credit: 1,303,001 RAC: 1 |
According to science fiction science Dyson spheres couldn't be detected until accidentally stumbled upon. I wonder how a structure that totally encases a star to capture the energy of said star to power a civilization could ever be detected from another galaxy. Dyson spheres have had an appeal since they were first imagined, but has anyone ever sat down and tried to figure what it would take in real terms? The amount of raw materials required from a single solar system and what it would take to produce the components? The atmosphere on the interior surface over a million times the volume of all the planets in the system? How many assumptions are we required to make in order for these things to be possible? Do all those assumptions really add up to something likely enough to be actively searching for? If we really think anyone out there has that kind of know-how then why aren't we actively looking for Ringworlds, as well? They're just as plausible with the same assumptions, and probably cheaper, too. |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30651 Credit: 53,134,872 RAC: 32 |
Further, any form of waste heat produced by whatever technologies are actually in use may have be reduced to the point that we simply can't detect it.All thermal systems with a heat source must have somewhere to radiate the heat. Stars do this by radiating it into deep space. If you put a Dyson sphere around a star, then the star radiates onto the interior surface of the sphere which gets hot. There being no perfect insulating material it follows the outside surface of the sphere must get hot. That surface radiates into deep space. There are no methods to escape the laws of thermodynamics. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1384 Credit: 2,098,506 RAC: 5 |
The laws of thermodynamics may well hold for any technology, whether that involves a Dyson sphere, or not, but that wasn't my point. Greater efficiency in technology than we are currently capable of even imagining, might reduce its heat signature to the point that we couldn't detect it at intergalactic distances. |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30651 Credit: 53,134,872 RAC: 32 |
The laws of thermodynamics may well hold for any technology, whether that involves a Dyson sphere, or not, but that wasn't my point. Greater efficiency in technology than we are currently capable of even imagining, might reduce its heat signature to the point that we couldn't detect it at intergalactic distances. No. Total energy of a sun or a Dyson sphere around a sun is the same. All you have done is change the frequency. It shifts towards the infrared and becomes brighter, in IR, than the star alone. Remember the energy frequency relationship of photons. Also remember the universe is more transparent in the IR than the visible. So if we could see the star without the Dyson sphere, we can see the Dyson sphere. Might not know what it is, but we know it is there. |
William Rothamel Send message Joined: 25 Oct 06 Posts: 3756 Credit: 1,999,735 RAC: 4 |
Please explain how we are to look at a star in another galaxy that may be 300 million light years away or more. |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30651 Credit: 53,134,872 RAC: 32 |
Please explain how we are to look at a star in another galaxy that may be 300 million light years away or more. The usual methods work fine. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1384 Credit: 2,098,506 RAC: 5 |
As I indicated before, our own ideas about a superior technology are likely to fall far from the mark. Still, it's possible to try to imagine a way in which a waste-heat-emitting surface, like the outside of a Dyson sphere might turn out to be much less conspicuous in the infra-red than expected. We know, of course, that a Dyson sphere would be made up of a multitude of objects, not a solid shell. Perhaps these objects could be fashioned so as to convert waste heat on their outer surfaces to even lower energy radio frequencies. By their size, shape and distribution these objects might be arranged to direct radio frequency energy in particular directions. Such beams could conceivably be used to detect and characterize asteroids and comets with orbits that would intersect the sphere, and so, possibly damage it. All of this could make for a Dyson sphere much less conspicuous in the infra-red, and much less likely to be detected. |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30651 Credit: 53,134,872 RAC: 32 |
As I indicated before, our own ideas about a superior technology are likely to fall far from the mark. Still, it's possible to try to imagine a way in which a waste-heat-emitting surface, like the outside of a Dyson sphere might turn out to be much less conspicuous in the infra-red than expected. If you go colder to radio, then it is even brighter than the normal background. Again remember the energy frequency relationship of photons. To transfer the same amount of energy with low frequency photons you need a lot more of them! Also remember our body temperature is in the infrared. I don't think advanced beings would be happy with temperatures down to radio, say liquid nitrogen. Translation, they are going to keep the temperature of the sphere somewhat above the freezing point of water and somewhat below the boiling point of water; in the Goldilocks zone. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1384 Credit: 2,098,506 RAC: 5 |
If the radio emissions are formed into narrow beams, as I suggested, there is a very good chance that they will not point in Earth's direction; they stand a good chance of not being detected by us, despite being brighter than background radiation in the radio range. The inhabited objects making up the Dyson sphere could be roofed-over on the star-ward side with something like very efficient photovoltaic cells that convert light and 'room temperature' infrared to electricity. This could be fed to radio frequency emitters on the outer side of the objects. |
KLiK Send message Joined: 31 Mar 14 Posts: 1304 Credit: 22,994,597 RAC: 60 |
The laws of thermodynamics may well hold for any technology, whether that involves a Dyson sphere, or not, but that wasn't my point. Greater efficiency in technology than we are currently capable of even imagining, might reduce its heat signature to the point that we couldn't detect it at intergalactic distances. in 1930 cars had about 8liter engines with about 30HP... now we have 1liter engines with up to 100HP! OK, d efficiency goes up...but also d consumption - 'cause of the availability of d engines & cars! ;) non-profit org. Play4Life in Zagreb, Croatia, EU |
W-K 666 Send message Joined: 18 May 99 Posts: 19062 Credit: 40,757,560 RAC: 67 |
Could this be the reason? Earth was one of the universe’s first habitable planets Earth was one of the first habitable planets in the universe, according to a new study. |
KLiK Send message Joined: 31 Mar 14 Posts: 1304 Credit: 22,994,597 RAC: 60 |
Imagine what would happen, if human weren't dominant species...& that dinosaurs never died by a catastrophic event in past?! Would dinos still use dogs & monkeys for a 1st flights into Earths orbit? :/ non-profit org. Play4Life in Zagreb, Croatia, EU |
Andrew McAtee Send message Joined: 3 Aug 15 Posts: 2 Credit: 101,709 RAC: 0 |
The study in question was searching for signs of a Type III civilization capable of harnessing the energy of an entire galaxy via extreme mid-infrared emission. The signs they did find were explained away by natural phenomena. First of all, that does NOT mean there is NO life, or even no ingelegent life in those galaxies. It means they did not find EVIDENCE of Type III. We're a type I civilization, and there is a whole class of Type II still. That means they would not have even seen an exact clone of earth in their study. Please read the papers, and not just media headlines. :) |
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