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Small interstellar payloads
Since colonization in the future is likely to accomplished by means of
sending a microscopic "seed" of self-reproducing machinery (the "astro-chicken"), I was wondering if there has been much thought on what propulsion system would be best to send such a payload on an interstellar journey. For instance, while antimatter seems like a ridiculously expensive proposition in the human case, for an extremely small payload it seems conceivable that it could be cost effective. On the matter of laser propulsion, how tightly could we focus a laser beam at an interstellar distance? What would be the effect of having essentially no payload mass on such a system? |
#2
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Small interstellar payloads
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#3
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Small interstellar payloads
alexandershepp;
Since colonization in the future is likely to accomplished by means of sending a microscopic "seed" of self-reproducing machinery (the "astro-chicken"), I was wondering if there has been much thought on what propulsion system would be best to send such a payload on an interstellar journey. Ra--Rn--ion at greater density and much improved exit velocity is offering perhaps 100 fold improvement over the existing Xe--ion, as well as Ra--Rn--ion is good for way more than 1600 years w/o refrigeration, and otherwise perfectly capable of exceeding 10% 'c'. There's also the option of Ra--LRn--Rn--ion that's worth a bit of phase shift energy as added trust, as this element changes from a high-pressure liquid form of Rn becomes a vapor of fast moving hot ions. For instance, while antimatter seems like a ridiculously expensive proposition in the human case, for an extremely small payload it seems conceivable that it could be cost effective. And don't forget seemingly lethal, although antimatter propulsion becoming sufficiently speedy to boot, say conservatively 0.5 'c'(150,000 km/s) up to the obvious maximum of achieving 'c', whereas colliding with so much as a dust-bunny can also become lethal. However, a terminal velocity comet like bow-wave should help to divert the smaller stuff. On the matter of laser propulsion, how tightly could we focus a laser beam at an interstellar distance? What would be the effect of having essentially no payload mass on such a system? Why bother to use laser as propulsion when the exchange of raw information is so much more valuable, and it's available at the speed of light as being worthy of nearly 300,000 km/s. I believe 0.05 mr is doable and at best offering a propulsion worthy of eventually achieving 0.5 'c' (150,000 km/s), although on behalf of our deploying interstellar communication packets is where that would simply demand a space-based laser cannon or at least a moon-based version in order to minimize the laser beam divergence caused by our badly polluted and otherwise H2O rich atmosphere. Ideally LL-1 and if need be LL-2 are a couple of sufficiently nearby locations worthy of having that laser cannon situated, with 1 TJ/ms or perhaps 1000 TJ/us worth of photon energy potential seems a bit of a stretch but otherwise technically doable. For the interstellar application, the given spectrum should be configured a little different than whatever's the prime output of our sun. Perhaps using 337 nm or of something longer than 900 nm would become noticed better off than 532 nm. For practice, why not try 425 nm (+/- 25 nm) or even as great as 532 nm for accomplishing something a whole lot closer to home, like Venus? Sorry that none of what I have to offer is of nearly scifi "VN technology" or even all that laser sailing worthy, just plain old conventional physics-101 and of believable hard-science at work. You know, the same old energy-in = energy-out sort of stuff, and otherwise doable from damn near what's off the shelf, like setting up a laser communications platform at LL-1 or upon our moon, and always the TRACE-VL2 platform that's specifically on behalf of the Earth/Venus interface, along with continued and considerably more advanced solar/TRACE research as a bonus. - Brad Guth (thinking pro life on Venus) |
#4
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Small interstellar payloads
Sorry that none of what I have to offer is of nearly scifi "VN
technology" or even all that laser sailing worthy, just plain old conventional physics-101 and of believable hard-science at work. VN technology is hard science, particularly the CAD/CAM route. Interstellar travel is a long way off admittedly. In fact CAD/CAM tells us that any robot worth having, any robot that can perform household tasks and assemble flatpacks is a potential VN. |
#6
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Small interstellar payloads
I have no doubt that "VN technology is hard science" because, my
LSE-CM/ISS is actually highly based upon employing robotics of a sufficient AI form of applied VN technology. Unfortunately, most of humanity can't hardly grasp much of anything unless it's related to protecting their sorry butt. People do have difficulty assembling their flatpacks. I think if someone like IKEA did the research, not to produce a VN machine but a flatpack assembler they would get a payback. The Pons Assinorum is in fact the flatpack. |
#7
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Small interstellar payloads
Compared to the naysayism of our NASA, IKEA might even be VN technology
overkill. A "flatpack assembler" sounds perfectly interesting and it's certainly of what's doable without going all that much robotic postal. What's the maximum individual deployment capability of "flatpack" tonnage that can be gotten into the LL-1 orbit, say if given a month to get it there? - Brad Guth |
#8
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Small interstellar payloads
What's the maximum individual deployment capability of "flatpack"
tonnage that can be gotten into the LL-1 orbit, say if given a month to get it there? I have descibed thisd as the Pons Assinorum - The bridge of asses. This means that having done FP assembly we can chart a route. We need our PA, the next thing we need is a replicatable route with all the components CAD specified. Now everytingh that goes into space today is CAD specified, it is difficult to concieve of anything that isn't. The question that should be asked is the weight of seed, and seed replication rate. There may in fact be a tradeoff between these two things. Mass production is very efficient in producing a large volume of widgets but to mass produce you need factories for every part and an enormous seed weight. To some extent we have to think of how things were done in the pre industrial age. Not quite we do have electricity and the high precision of robotic motion. Not available in the Middle Ages. |
#9
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Small interstellar payloads
In article ,
pete wrote: A question arises then about the design requirement. How much of a hurry are you in? The simplest goal is simply to exceed solar system escape velocity with vast numbers of probes, preferably billions, dispersed widely. This may take millions of years to achieve successful "seeding", but could be relatively easy to accomplish... Bear in mind that the probes will be taking cosmic-ray damage while in transit, and won't have energy available for in-flight repairs. A century is unlikely to be a problem, but transit times of millions of years will leave few to none of the probes functional at the destination. This is one disadvantage of going really small... -- spsystems.net is temporarily off the air; | Henry Spencer mail to henry at zoo.utoronto.ca instead. | |
#10
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Small interstellar payloads
I said a Pons Assinorum. Hubble is more complicated than a wardrobe but
complexity means nothing to AI. All you need is a bigger memory. Also an IKEA system could quite esily replace the gyros on Hubble. |
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