Posted on 12/18/2003 8:37:33 AM PST by KevinDavis
When Star Trek's U.S.S. Enterprise hit the television screen in 1966, the science fiction series had trouble finding its own space and time slot.
Decades later, a similar visionary zeal to seek new worlds and new civilizations is a factual enterprise for a new generation of galactic explorers. They are taking on spacetime and hoping to boldly go where no spacecraft has gone before -- out to far-flung stars and the planets that circle them.
(Excerpt) Read more at space.com ...
Confucius say: "He who posesses Google posesses the whole world":
I don't watch Stargate. My conclusion is: either advanced technological intelligences are very rare or interstellar travel is impossibly difficult or both. IF advanced technological civilizations are not rare then it is probable that more than one would hit upon the idea of the Von Neumann approach to exploration. Imagining that all such programs were conveniently hijacked or 'misused' is simply silly.
Now, as to your lack of logic: B) There's a difference between "common" and "easy" or "quick". You postulate that if evolving species and advanced intelligence is common, it had to be quick too.
Quite the opposite. The universe is ~15 billion years old. You have (evidently) no idea of the time scale. As I mentioned, life began relatively quickly on Earth (~3.8 billion years ago) but modern life--including us--is the result of only the last 600 million years given Snowball Earth. Sagan's point--which remains valid despite all objections posted here--is that we are a newly-hatched technological civilization, only a century or two old. So we are the latest, arriving in the blink of an eye. Amazing hubris to believe we are the "first" or most advanced. Second-generation stars were probably quite capable of accumulating enough heavy elements, and many 3rd-generation stars are older than our Sun. The entire human race--all the way back to Homo Habilis--is only a few hundred thousand years old; another eye blink.
"I also find the notion that intelligence is the "intent", or "endpoint" of evolution to be silly. Sure, ONCE intelligence is introduced to a planet in a particular species, that species will likely dominate their planet, but you still need the freakishly unlikely set of genetic accidents for it to happen."
You make my argument again. Once more: "My conclusion is: either advanced technological intelligences are very rare or interstellar travel is impossibly difficult or both. IF advanced technological civilizations are not rare then it is probable that more than one would hit upon the idea of the Von Neumann approach to exploration."
"Now, GIVEN ENOUGH TIME, even the freakishly unlikely becomes likely. The odds of intelligence developing through random mutation is an unknown variable X. X could mean that there's even odds that it'll happen once in a million years, once in a billion years, once in a hundred billion years - we have no idea. X could be anything. You are assigning a low value to X based on zero evidence. Even -with- "billions and billions", it may -take- billions and billions of planets working for fifteen billion years to produce the first half-dozen or so intelligent civilizations."
Why do you insist on continuing to repeat me? Again: My conclusion is: either advanced technological intelligences are very rare or interstellar travel is impossibly difficult or both. IF advanced technological civilizations are not rare then it is probable that more than one would hit upon the idea of the Von Neumann approach to exploration.
"It may easily be that, given -another- ten billion years, there'll be a hell of a lot more advanced races out there, and we happen to be ahead on the curve. No one can know. But you're conveniently introducing your own timetable for the likelihood of such a thing occuring with zero data for backup beyond our own experience."
If this is so then we are alone. If we are alone (he said with a weary sigh) then either advanced technological intelligences are very rare or interstellar travel is impossibly difficult or both. IF advanced technological civilizations are not rare then it is probable that more than one would hit upon the idea of the Von Neumann approach to exploration.
--Boris
Still doesn't mean hyperlight travel can't be done...
DESPITE "Circumstances" which would "Dictate That" our "Human Culture" should Perish; We Go On!!...
Perhaps We are "Tougher Than" That Which Challenges Us!!
Doc
YES!! Seeing all the episodes of Star Trek, most of them have shown some very appealing female aliens.
N.O.W.? Put THAT in your pipe and smoke it!
Quantum entanglement seems to be the most promising line of research in this area. But, as Boris insists, and he is a reasonable fellow, if it were possible it would already be done by someone and they would be very obviously HERE now.
The alternative is that if FTL is possible economically, then there is no one else out there. This is very likely. We appear to be alone, and as my worldly-wise uncle says: things are as they appear to be 95% of the time.
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Named after the Hungarian-born American mathematician John von Neumann who, among many other achievements, developed a theory of machines that can make exact copies of themselves. The potential advantages of using self-replicating robot spacecraft for galactic exploration was discussed by Chris Boyce in his book Extraterrestrial Encounter: A Personal Perspective (Chartwell Books, New York, pp. 113-124, 1979).1
Boyce, in turn, has said he got the idea from a chapter entitled "The Likelihood of the Evolution of Communicating Intelligences on Other Planets" (ch. 4) written by Michael A. Arbib in the 1974 Ponnamperuma-Cameron book Interstellar Communication: Scientific Perspectives (pp. 63-66).
Arbib wrote an even earlier paper, in 1969, in which he discusses self-replicating automata (SRA) based on von Neumanns/Burks seminal paper published in 1966. Boyce, in his book, envisaged the following scenario.
Initially, a von Neumann probe, consisting of an interstellar propulsion system and a universal von Neumann replicator with human-level intelligence, would be launched from the home star toward a neighboring stellar system. Upon arrival it would seek out raw materials, from local sources such as asteroids, and use these to make several copies of itself (including its rocket engines).
The copies would then be launched at the next set of neighboring stars. This process would be repeated, over and over again, so that increasing numbers of identical probes would be involved in penetrating ever more remote regions of the Galaxy.
Having dispatched copies of itself, a probe would begin to explore the star system in which it found itself. It would conduct scientific research and transmit the results back to the point of origin.
It could also be used as a means of colonization by constructing an artificial life-sustaining environment and then implanting this with synthesized fertile egg-cells bearing genomes transcribed from the probe's computer memory.
Eiseley has suggested that the embryonic individuals of such a colony could be tended by robots, also built by the probe, until they were old enough to function independently. They would then be free to develop their own civilization around the host star.
The great advantage of a von Neumann probe is that, being a universal machine, it can be used for any purpose at its target system depending on the instructions sent out to it from its ultimate creators.
Consequently, as the creators made technological advances at home they could reprogram a remote von Neumann probe, for example, to build faster rocket engines for the next generation of probes or more sensitive sensing equipment with which to study its host stellar system.
How rapidly the Galaxy could be completely explored and colonized in this way depends on several factors, including the interstellar transit times of the probes (see interstellar travel), the speed at which they reproduce and carry out other tasks within the host systems, and the specific strategy used for interstellar colonization.
Frank Tipler, writing after Boyce et al, and borrowing the idea of von Neumann probes from them, has used the concept as an argument against the existence of intelligence elsewhere in the Galaxy. He proposed a conservative value of 300 million years, or less than 5% of the present age of the Galaxy, for complete galactic colonization. He assumed the von Neumann probe approach to be so logical and economical that it would be commonly adopted by advanced civilizations. According to this view, there should be a significant and obvious presence of such devices within the solar system. Yet, no such presence has been detected. Tipler therefore draws the conclusion that we are the only intelligent race among the Galaxy's several hundred billion stars (Tipler's Argument). The validity of this conclusion has been questioned by, among others, Sagan and Newman (see Sagan's Response).
The idea of using automatically exponentiating systems has been investigated for extraterrestrial mining by von Tiesenhausen and Darbro at NASA's Marshall Spaceflight Center.2
See Bracewell probes, extraterrestrial probes, and SETA.3, 4
Thanks to Scot Stride (NASA/JPL) for details of Boyce's and Arbib's writings on this subject, and for pointing out that they have priority over Frank Tipler on the issue of von Neumann probes.
References
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1. Boyce, Chris. Extraterrestrial Encounter: A Personal Perspective. London: David & Charles, Newton Abbot (1979).
2. von Tiesenhausen, G., and Darbro, W. A. "Self-Replicating Systems," NASA Technical Memorandum 78304. Washington, D.C.: National Aeronautics and Space Administration (1980).
3. Freitas Jr., Robert A. "A Self-Reproducing Interstellar Probe," Journal of the British Interplanetary Society, 33, 251-264 (1980). Abstract: Bracewell and Frietas have discussed the possible superiority of interstellar probes in missions of galactic exploration and recently Calder and Boyce have raised the issue of self-organizing machines in related contexts. In this paper a preliminary sketch of a self-reproducing starprobe is presented, with generation time ~103 years given a ~10-fold improvement in current human space/manufacturing technology.
4. Valdes, F., and Freitas, R. A. "Comparison of Reproducing and Non-Reproducing Starprobe Strategies for Galactic Exploration," Journal of the British Interplanetary Society, 33, 402-408 (1980). Abstract: Bracewell has suggested the use if nonreproducing messenger probes for interstellar exploration, and Freitas has examined the feasibility of self-reproducing automated devices in the same context. The present paper compares reproducing and nonreproducing strategies for missions of interstellar and galactic discovery. Self-reproducing probes are found to be the method of choice for active exploration programs lasting >106 years, involving searches of >106 target stars to distances > 1000 light-years in the Galactic Disk, and are superior to one-shot "Bracewell Probes" for searches of >103 stars to distances > 100 light-years in the Galactic Disk. Any nonreproducing alien probes discovered in the Solar System during the normal course of future SETI research would most likely have been sent by extraterrestrial civilizations located within a approx. 1000 light-year radius of the Sun, whereas any self-reproducing devices similarly detected probably originated far outside the exploration sphere.
Neat concept!!! I hope they will still take Visa!
Out of curiosity, what would be the benefit to visiting Jupiter?
Of what possible use is a baby?
I was asking an honest question. I don't know enough about Jupiter to have a clue.
If a non-gun person asks me a stupid question I attempt to enlighten them. Sarcasm has its place and dealing with a honest question is not one of them.
To answer your original smart-ass question, I have a wonderful 16 year old son and a brilliant 13 year old daughter that my wife of 18 years and I have raised from babies.
Thanks for your input.
This goes to my question, why Jupiter. As I understand it, humans have limited resources, so I am asking what Jupiter has to offer. If I need bullets and I can only make one trip I don't go to Radio Shack.
I simply wanted to know why Jupiter and not somewhere else first.
To see what we could find. Life, for example. Many people who are experts in the subject think a good chance of finding extraterrestrial life would be on Europa, with it's subsurface ocean. There are two other icy moon as well. Where there's water, there is a better chance of finding life than where there is not. The JIMO program I am involved with involves the launching of an unmanned mission to visit these three icy moons. The craft has the capability of going into orbit around a moon, making observations for a while, then leaving it and going to another moon. This is a capability wholly new for outer planet missions. It's star trek-type stuff.
But, in the end, its the nature of man and his curiosity, the need to explore and find out new things, that lies at the heart of the drive to do these things. I hope we don't lose that, because if we do we will have lost a vital component of the human spirit, something that has been with us since the first person among early man threw a log in a river and hopped on for the ride. Where that journey will take us, I don't know, but, if we can manage to survive, I think it's end will be far, far away.
NASA, Russia, and ESA have between them already sent probes to most or all major planets and many of their moons and several asteroids and comets. When interstellar probes are sent, thney will also go in all directions. It's not a question of picking just one.
If you had said Europa it would have made more sense to me. I was focused on Jupiter as a target, not a system.
Thanks again,
"ALL THESE WORLDS ARE YOURS...EXCEPT EUROPA. ATTEMPT NO LANDING THERE. ALL THESE WORLDS ARE YOURS...EXCEPT EUROPA. ATTEMPT NO LANDING THERE..."
I understand that. My point remained, before chimera's response, that if you have 1,000,000,000 probes and 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000+ possible destinations, some choices will have to be made, and for a valid reason other than what the heck.
This makes it twice this week that I have been warned to stay away from Europa!!!
Am I becoming paranoid??
;<)
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