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Messages 7645 - 7676 of 8999   Oldest  |  < Older  |  Newer >  |  Newest
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7645
... Unfortunately bringing an asteroid into GEO is a half dozen orders of magnitude more difficult than even building the T1000 SE. Besides, manufacturing an...
Andreas
awnd329
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Jan 2, 2007
3:18 am
7646
The whole point of this thread, was to consider if an Earth based SE was possible, with today's tech. It is a huge undertaking, but I believe possible. Findng...
Herbert Murray
hcm1955
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Jan 2, 2007
6:57 am
7647
... Space based manufacturing is not exactly today's tech. Nor is diverting asteroids, or MEMS based climbers. I am afraid we are stuck with the 60 GPa...
Andreas
awnd329
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Jan 2, 2007
3:34 pm
7648
... How do you figure? And why does the asteroid have to be in GEO? Moving an asteroid can be done with (relatively) low-power systems (and some patience)....
Patrick Boake
pbboake
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Jan 2, 2007
3:35 pm
7650
... I believe we are closer to a MEMS based climber, than we are a 60GPa ribbon. Moving an asteroid to GTO (possibly with solar sails) is also something we...
Herbert Murray
hcm1955
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Jan 2, 2007
9:02 pm
7651
... Perhaps. If so, the SE will have to be relegated back to the realm of science fiction. Not that a MEMS based climber would help solve the problem, at all. ...
Andreas
awnd329
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Jan 2, 2007
9:29 pm
7652
... What size asteroid are we talking about? This one here: http://en.wikipedia.org/wiki/951_Gaspra weighs in at 10^16 kg. Which orbit do you want it in? Any...
Andreas
awnd329
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Jan 2, 2007
9:29 pm
7653
... Where did you get this idea? A delta-v of 2 km/s takes at least 2 MJ per kg, or 2*10^22 J for easy-to-reach 951 Gaspra. If you allow 100 years, you need to...
Andreas
awnd329
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Jan 3, 2007
12:15 am
7654
... If you are waiting for CNTs to be develop for ribbon materiel then an Earth base SE is indeed in the realm of Sci Fi (At least right now). If you consider...
Herbert Murray
hcm1955
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Jan 3, 2007
4:18 am
7655
Sorry that the below is a little long-winded, but I went into full-on geek mode. ... It sounds like a lot, and it is if you use artificial nuclear power plants...
Ed Minchau
spider_boris
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Jan 3, 2007
9:28 am
7656
... Also Solar Thermal Rocket (STR) might be considered. This would require the asteroid materiel to be ground up and used as feedstock for some type of solar...
Herbert Murray
hcm1955
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Jan 3, 2007
1:11 pm
7657
... This could work. You need to be mindful that concentration of sunlight with mirrors is limited to 10,000-fold or so because of its poor collimation. I am...
Andreas
awnd329
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Jan 3, 2007
4:06 pm
7658
For what it is worth is a list of some 3000 + NEO, with orbital information. If someone that knows something about orbital mechanics ( I don't), wants to help...
Herbert Murray
hcm1955
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Jan 3, 2007
4:47 pm
7659
... velocities. ... I think what this means is that the absolute maximum temperature you can achieve using optically focussed sunlight is that of the sun's ...
Andreas
awnd329
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Jan 3, 2007
5:06 pm
7660
... mirrors is ... am not ... I believe a more realistic option is the nuclear or modified RTPs using water (from the asteroid) as the working fluid. As long...
Herbert Murray
hcm1955
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Jan 3, 2007
5:40 pm
7661
... systems (and some patience). ... Space.com <http://www.space.com/adastra/060209_adastra_mining.html> [emphasis added] "About 10% of Near-Earth Asteroids...
Patrick Boake
pbboake
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Jan 3, 2007
5:44 pm
7663
... the...
Herbert Murray
hcm1955
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Jan 3, 2007
6:21 pm
7664
... Note the picture on slide 7 and imagine that built on an asteroid. And that only represents one step of many. Andreas...
Andreas
awnd329
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Jan 3, 2007
7:49 pm
7665
... Huh? As far as I can tell this does not at all talk about moving entire asteroids. Just "asteroidal resources", which I take to be minerals already...
Andreas
awnd329
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Jan 3, 2007
7:57 pm
7666
... Oh, but you do care. If you want to accelerate one half of the asteroid by 2 km/s, you need to eject the other half at a relative velocity of 4 km/s. That...
Andreas
awnd329
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Jan 3, 2007
8:28 pm
7667
1. More info on manufacturing carbon fibers: propylene http://en.wikipedia.org/wiki/Propylene ammonia ...
Herbert Murray
hcm1955
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Jan 3, 2007
8:30 pm
7668
I will catch a lot of negative feedback for this, but: I am beginning to suspect that you are shooting down a lot of the SE ideas, not that you don't believe...
Herbert Murray
hcm1955
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Jan 3, 2007
9:15 pm
7669
... Justly so. Let me de-lurk to be the first to cry "foul"! ... Andreas's arguments (from my reading) have been entirely factual and science related...
Jo Jaquinta
jim_plummer
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Jan 3, 2007
10:12 pm
7670
I've gotten hotter than that. I've boiled steel (not melted, *boiled*) using a Fresnel lens. The key is to use non-imaging optics. ...
Ed Minchau
spider_boris
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Jan 4, 2007
2:33 am
7671
... The boiling point of iron is 3134 K http://www.webelements.com/webelements/elements/text/Fe/heat.html No kind of optics will improve the collimation of...
Andreas
awnd329
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Jan 4, 2007
3:47 am
7672
... I have not mentioned the Aerovator, and my only interest in this discussion is in supporting the SE by keeping discussion within rather generous bounds of...
Andreas
awnd329
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Jan 4, 2007
3:56 am
7673
... OK my comment was out of line. But I do get the feeling that when I stretch the possibilities, and introduce techs like robotic MEMS, coil guns, and the...
Herbert Murray
hcm1955
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Jan 4, 2007
5:29 am
7674
I said steel, not iron. The boiling point is slightly higher. And, it boiled instantly, my temperature was well above the boiling point. ... ...
Ed Minchau
spider_boris
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Jan 4, 2007
6:46 am
7675
All modern rocket designs have a operating temps higher than the rated temp of the materiel that they are made from. By pumping the fuel thru the skin of the...
Herbert Murray
hcm1955
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Jan 4, 2007
1:16 pm
7676
... All the plans for moving asteroids I've seen involve at least one factory using asteroid dirt feedstock, so it is hard for me to see how it would not be...
Andreas
awnd329
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Jan 4, 2007
4:02 pm
Messages 7645 - 7676 of 8999   Oldest  |  < Older  |  Newer >  |  Newest
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