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When a reasonable person fails to attain his
goal, he either abandons the goal or tries a different method of attaining the goal. An idiot is usually defined as someone who responds to failure by doubling his efforts. NASA is an ossified bureaucracy, but they are not idiots. When their big SETI program failed, they abandoned it. SETI@homers ignore their failures and have little if any interest in modifying their search method. Worse yet, they seem to believe that some extraterrestrial civilizations have been sending powerful microwave beams toward the Earth for millions of years. Why would the extraterrestrial tax payers support such an effort? If we ever receive their message it will say something like: "Life is absurd. Have a happy suicide." |
#2
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Andrew Nowicki wrote:
When a reasonable person fails to attain his goal, he either abandons the goal or tries a different method of attaining the goal. An idiot is usually defined as someone who responds to failure by doubling his efforts. NASA is an ossified bureaucracy, but they are not idiots. When their big SETI program failed, they abandoned it. SETI@homers ignore their failures and have little if any interest in modifying their search method. Worse yet, they seem to believe that some extraterrestrial civilizations have been sending powerful microwave beams toward the Earth for millions of years. Why would the extraterrestrial tax payers support such an effort? If we ever receive their message it will say something like: "Life is absurd. Have a happy suicide." WOW ($1) -- It Came From C. L. Smith's Unclaimed Mysteries. http://www.unclaimedmysteries.net "Bill Funk" said in rec.photo.digital: "Is this actually part of your plan? To use tag lines to show your contempt, while showing that you really have so little understanding?" |
#3
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![]() In semi-infinite wisdom Andrew Nowicki answered: When a reasonable person fails to attain his goal, he either abandons the goal or tries a different method of attaining the goal. An idiot is usually defined as someone who responds to failure by doubling his efforts. NASA is an ossified bureaucracy, but they are not idiots. When their big SETI program failed, they abandoned it. No, congress told them to stop spending money on SETI. NASA would spend trillions on SETI if they had the funds. NASA cannot even account for where their current funds go, after a GAO audit. SETI@homers ignore their failures and have little if any interest in modifying their search method. What failures? SETI@home is an open research project. Some expect it to work, but many, myself included, think even negative evidence worth having. We'll know what ain't there at least. Worse yet, they seem to believe that some extraterrestrial civilizations have been sending powerful microwave beams toward the Earth for millions of years. I don't recall any search for extragalactic sources. I think it's more of a 'what-if' question that's being asked, and answered mostly with voluntary computer power and a hitched ride on Arecibo. Seems quite acceptable to me. No one's being lied to, unless they are being told that the Drake equation is proof of ET civilizations (it does seem a religion to many). Why would the extraterrestrial tax payers support such an effort? I'm reminded of a quote by Woody Allen in Without Feathers... To you I'm an athiest, to god I'm the loyal opposition. If we ever receive their message it will say something like: "Life is absurd. Have a happy suicide." So I take it you're just trolling. Have a nice day. Rich |
#4
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In sci.space.policy Rich wrote:
In semi-infinite wisdom Andrew Nowicki answered: When a reasonable person fails to attain his goal, he either abandons the goal or tries a different method of attaining the goal. An idiot is usually defined as someone who responds to failure by doubling his efforts. NASA is an ossified bureaucracy, but they are not idiots. When their big SETI program failed, they abandoned it. No, congress told them to stop spending money on SETI. NASA would spend trillions on SETI if they had the funds. NASA cannot even account for where their current funds go, after a GAO audit. Yes, but that was not the reason of that funding cut. SETI@homers ignore their failures and have little if any interest in modifying their search method. What failures? SETI@home is an open research project. Some expect it to work, but many, myself included, think even negative evidence worth having. We'll know what ain't there at least. More correctly, we know what wasn't where some time ago. Remember, radio signals move at a finite speed, so instead of "now" it is always looking at the past. A positive result depends on there having been a civilisation that was a strong radio source emitter k years ago at the distance of k lightyears. This is where Drake equation comes into play and why you need not pay attention to whetever it then goes off to conquer the stars or not. The chance of detecting a signal from stars that are say 5000 - 10000 lightyears awy depends on the chance of there having been a civbilsation in the radio noise phase among that relatively largis amount of stars during teh past 5000-10000 years ago (though to be sure about outermost stars, we have to listen for 5000 more years). Its an odd kind of archeology ;-) Rich -- Sander +++ Out of cheese error +++ |
#5
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![]() In infinite wisdom Sander Vesik answered: In sci.space.policy Rich wrote: In semi-infinite wisdom Andrew Nowicki answered: When a reasonable person fails to attain his goal, he either abandons the goal or tries a different method of attaining the goal. An idiot is usually defined as someone who responds to failure by doubling his efforts. NASA is an ossified bureaucracy, but they are not idiots. When their big SETI program failed, they abandoned it. No, congress told them to stop spending money on SETI. NASA would spend trillions on SETI if they had the funds. NASA cannot even account for where their current funds go, after a GAO audit. Yes, but that was not the reason of that funding cut. The point is that NASA will spend as much money as it can get, regardless of outcome. Like all bureaucracies, status is determined by budget and headcount, not by science, results, or efficiency. SETI@homers ignore their failures and have little if any interest in modifying their search method. What failures? SETI@home is an open research project. Some expect it to work, but many, myself included, think even negative evidence worth having. We'll know what ain't there at least. More correctly, we know what wasn't where some time ago. Remember, radio signals move at a finite speed, so instead of "now" it is always looking at the past. I don't see it as a useful distinction, SETI has no hope (IMHO) of detecting anything not in the immediate stellar neighborhood. Any signal's source cannot be older than tens of years, maybe a hundred years at best. A positive result depends on there having been a civilisation that was a strong radio source emitter k years ago at the distance of k lightyears. This is where Drake equation comes into play and why you need not pay attention to whetever it then goes off to conquer the stars or not. What do you claim the Drake equation will tell you *if* an signal apparently from ET is received? It will tell us no more then than it does now, which is what our current baseless guess on the frequency of intelligent ET life is. The chance of detecting a signal from stars that are say 5000 - 10000 lightyears awy depends on the chance of there having been a civbilsation in the radio noise phase among that relatively largis amount of stars during teh past 5000-10000 years ago (though to be sure about outermost stars, we have to listen for 5000 more years). Its an odd kind of archeology ;-) Indeed, a civilization with non-directional transmitters stronger than stellar sources at waterhole frequencies. Are you working on a plot for Enterprise by any chance? Rich Rich |
#6
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Rich wrote in message ...
Some expect it to work, but many, myself included, think even negative evidence worth having. We'll know what ain't there at least. Ditto: I _expect_ seti@home to fail to find anything, but still think that not finding anything would be a useful enough result to justify the thousands of data blocks I've processed for them. At least we'll know that aliens with big non-directional radio transmitters are rare. Mark |
#7
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Mark wrote:
At least we'll know that aliens with big non-directional radio transmitters are rare. We have already learned that. What we need is a non-directional microwave receiver on the far side of the Moon. It would be a sort of phase-array radar in reverse -- lots of small receivers but no directional antennas. To reduce the noise, it would be used only during lunar night, when the surface of the Moon is cold. The advantage of the non-directional receiver is that it can detect signals coming from a broad solid angle. If the ET is using a weak transmitter and he aims a very narrow beam at randomly chosen stars, we have good chance of detecting his signal. |
#8
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Andrew Nowicki writes:
Mark wrote: At least we'll know that aliens with big non-directional radio transmitters are rare. We have already learned that. Not really. First, we have only looked a small portion of the frequency spectrum. If you turn on your TV, and see nothing on the first two channels you try, you can't tell if there is any signal (even a very strong one) on another channel. You need to try all the channels (or at least most) to conclude signals are rare. Second, our searches tell us nothing about the directionality of the source. We can't tell a bright omni-directional source from a less bright but directional one. What we need is a non-directional microwave receiver on the far side of the Moon. It would be a sort of phase-array radar in reverse -- lots of small receivers but no directional antennas. To reduce the noise, it would be used only during lunar night, when the surface of the Moon is cold. This is sound in theory, but has a bunch of practical problems. The biggest is that looking in all directions at once takes an enormous amount of computer power, far more than we have right now. (Basically, you need to phase and add all the elements, and do this as many times as there are beams from an equivalent sized conventional scope. There are shortcuts but not enough to make it practical.) Also, given the current technology, the lunar night is still not cold enough. The advantage of the non-directional receiver is that it can detect signals coming from a broad solid angle. Very true, plus it can study transients, which is very hard for conventional radio telescopes. The problem is that for the same amount of money, it is far less sensitive than a conventional telescope. So if you expect huge but infrequent signals, it's better, but if you are looking for lower power but always on signals, a conventional telescope is a better bet. It would make sense to try both. Lou Scheffer |
#9
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In article ,
"Andrew Nowicki " wrote: Mark wrote: At least we'll know that aliens with big non-directional radio transmitters are rare. We have already learned that. Even if we did detect a signal, we couldn't tell if it was directional at source. (We are almost at the point of being able to detect our analogue TV carriers at interstellar distances (see the 1 sq km array below), and those, whilst directed to try and avoid wasting power, are not strongly directional. What we need is a non-directional microwave receiver on the far side of the Moon. It would be a sort of phase-array radar in reverse -- lots of small receivers I would consider this to be multiple directional beams, rather than non-directional reception. As far as I know, the 1 square km array, which will be an earth based equivalent, won't normally attempt to form as many beams as there are elements, but rather a small number. However, such an array is beyond the wildest dreams of even conventional radio astronmers, let alone cash starved SETI searchers. As well as the problems of surveying and placing each element, the large amount of electronics involved will result in a system that will start to lose elements quickly and have no maintenance man to replace them. but no directional antennas. To reduce the noise, it would be used only during lunar night, when the surface of the Moon is cold. Modern receiver noise temperatures are generally a long way below ambient. The cryogenically cooled SERENDIP (S@H) receiver was actually replace by a non-cooled one with a lower noise. I believe the total system noise for this receiver is about 45K, of which about 12K is galactic noise and big bang backround, which can't be eliminated. Whilst I argue in another thread, that a pure phased array transmitter is future, rather than current technology, it is not that far off that it wouldn't be reasonable to assume that an ETI would form multiple beams to allocate the total power more effectively to likely targets. The advantage of the non-directional receiver is that it can detect signals coming from a broad solid angle. But only at the cost of doing a two dimensional fourier transform, and then doing the followup signal processing a number of times comparable to the number of elements. Remember that processing capability for space qualified equipment is rather moderate compared with what is on your desk top. Incidentally, with respect to the subject, there was concern amongst the professionals that the general public might expect a contact from S@H when the professionals, whilst hoping for one, thought that setting new upper bounds was the more likely outcome. This was before it went fully live. The concern was that there might be a backlash from the modern instant gratification culture, that might prevent funding of more sensitive future work. |
#10
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David Woolley wrote:
However, such an array is beyond the wildest dreams of even conventional radio astronmers, let alone cash starved SETI searchers. As well as the problems of surveying and placing each element, the large amount of electronics involved will result in a system that will start to lose elements quickly and have no maintenance man to replace them. Although I respect your technical expertise, I am not yet convinced that this array would be expensive to make and maintain. The array would be made of a large number of identical, mass produced panels. Damaged panels can be replaced with new ones. A small percentage of damaged panels does not seriously degrade the image quality. The main issue is how much data would have to be processed. If the array cannot filter out obvious noise, SETI@homers would be overwhelmed with noise. |
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