h a l f b a k e r yStrap *this* to the back of your cat.
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Your satellite on the fritz? Space agencies don't have a launch slot soon?
Not to fret! Simply deploy the SRL! At a touch of button, and some heaving, kicking the container and swearing, it activates deploying to it's full height of 1,500 miles.
Simply climb to the top and you can do the repairs
yourself.
Comes with built-in fibre-optic cabling to communicate with the person at the bottom supporting it for the inevitable "a bit to the left...no, no, your left, a bit more..." dialogue.
Also useful for (partly deployed, be careful about that) for painting high ceilings and getting cats out of trees.
//Oops, finally noticed the typo of 1.500 miles, and corrected it.
Space elevators
http://en.wikipedia...wiki/Space_elevator Thin atmosphere thinkers [4and20, Jun 06 2013]
Space elevators
http://xkcd.com/536/ [normzone, Jun 08 2013]
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[+] yes I think this is good. |
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I'll just take the elevator. |
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The sad truth is certainly the first 62 miles are extremely easy. 100 foot sections, made of bamboo, supported by hydrogen balloons, sections connected loosely with cable ties. |
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Leakage to be addressed by a pipe running up the side of the ladder, full of hydrogen, you wouldn't even need to pump it up there. |
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As for the other 1,438 miles,that's easier and yet harder at the same time. Lack of atmosphere, but then again, no cloud cover. I suggest an ion drive one each stage, ions being provided by hydrogen and electricity to make it work from solar panels. Or something like that. |
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I think this is perfectly halfbaked idea. I don't know why some people can't see merit in ideas like this! It's much easier than waiting for the satellite to come to you. |
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Ahem. In none of those accounts has anyone attempted to deal with the "a bit to the left, a bit more, hang on, back a bit" problem that's going to occur with meeting up with the satellite. |
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Did I not mention the bit where's there a (optional extra) tookit waiting for you up there, as there's nowt as annoying as getting all the way up there and finding you've left the allen keys behind again, and having to come all the way back down again. AC Clarke, eat your heart out. |
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Not to mention rungs 1,819,221 to 2,227,931 have been pre-emptively greased, just in case there is an angry giant up there, still trying to find out what happened to his transmutational goose. Strange how Clarke is silent on this matter... |
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//1.500 miles// [nmrm]
//waiting for the satellite to come to
you//[xandram]
//at 15000 mph, grab quickly//[lurch] |
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Instead of a many miles long ladder, a very tall extension ladder
that once climbed to the top launches the bottom ladder to the
top, and as it descends the climber climbs, and then the
bottommost ladder launches, and this process repeats until the
very tired climber is in space. |
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As seen in the Baron Munchhausen, but descending from the Moon on a rope...umlaut free version. |
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Is there some kind of halfbaked feud going on here?
Bigsleep seems awfully petulant |
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Yep, this should work! [+] |
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<here's GROG thinking, "...I wonder if anyone has snapped up the tool concession at 1,000 miles yet --- who wouldn't pay top dollar to buy a screwdriver they forgot to to bring with them after climbing that far?..."> |
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Thought it said 15000 miles, not stair master Stair masochist. |
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Oh then maybe the satellite can be attached to a kite, so you could just pull it down when you need to fix it. (better than waiting for your satellite provider all day!)
feud? [Bigsleep] meh- he's always grouchy. |
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The ladder part wouldn't work even if it were only one-and-a-half miles. Even a tapered permanent structure that high is currently impossible/impractical. |
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The satellite-intercept part wouldn't work if it were possible to build a tower one-thousand-five-hundred miles high. The satellites would go by too fast, and any ones lower would knock the ever-lovin' snot out of the tower. |
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Very few satellites orbit at around 1,500 miles up, by the way. |
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The humor doesn't outweigh the wrong. [-] |
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I beg to differ on the structural aspect. |
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Each section is basically independent and has, one way or another, a way to support it's own weight. Basically, they are just tied together as otherwise it'd be tricky climbing the ladder. You could remove every other section and it would still be up there, but then they would drift laterally. |
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As for the satellite interception, who said it was going to be easy? "We do this and other things not because they are easy but because they are hard." etc. |
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//You could remove every other section and it would still
be up there, but then they would drift laterally.// |
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Is your understanding of physics such that you think that is
true, or are you just dumbing for fun? |
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Ok, I genuinely cannot understand the confusion here. |
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Right, let's imagine a 100 ft ladder. It has hydrogen balloons attached to it, that support the ladder's own weight and keep it up in the air. |
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Now make another one exactly the same, then loosely connect the two, why would the top one create any downwards force on the bottom one? |
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Then multiply to make enough sections to cover the roughly 62 miles depth of the atmosphere. |
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Why would the top ladder be exerting any downwards force whatsoever on any of the ladders beneath it? |
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As for above the atmosphere, I was thinking ion drives. |
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I'm dumb enough in everyday life as it is. |
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and, thinking about it, there is a way to stop the damn thing moving downwards as you climb. Each ladder section has some spare balloons. As you to climb on the first ladder, hydrogen is released into the pipes sufficient to support your weight. In my case about 70m3 would be needed. |
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As my hand goes to the first rung of the ladder above, the hydrogen is then released upwards to that ladder's spare balloons. From the point of functionality it would be good to have cable ties able to support 100kg or whatever between the two ladder sections. |
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The hydrogen balloons will be able to lift the ladders just
fine in the lower atmosphere. Perhaps even up to
100,000 foot altitude. You ever tried picking up a 100
foot ladder? Any ladder that long is likely going to be tied
to a fire truck, or the side of a building in Hong Kong or a
mountainside in Tibet. Five 20 foot aluminum ladders will
make up the weight of a decent anvil. |
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Above 100,000 feet, you're going to need Freaking Huge
Balloons. That will cover your needs up to about 180,000
feet. Above that point, your hydrogen is no longer lighter
than the ambient air, and despite your thinking of ion
engines, ion engines have nowhere near sufficient thrust
to hold themselves up in a gravity well, let alone an extra
half-anvil or so of mass per engine. |
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Even if you switch over to ladder sections which are
single-strand dental-floss macrame, you still can't make it
up to 62 miles. A bit over half of that is going to be your
uttermost top limit. |
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Oh, but we were headed for fifteen hundred miles? That
doesn't float. |
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//Ok, I genuinely cannot understand the confusion
here.// - - - unless it's intentional. |
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(By the way, if you are talking about satellites that send
TV signals for your house - those are at 22,236 miles up
from a sea-level start. No more, no less. Not sure what
you'd be looking for at 1,500 miles - there's basically
nothing there.) |
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Very rough calculation as I am tired...and not using bamboo as I can't find anything sensible on the net at 11:50 at night....for 30 metres of 1" box aluminium 46.86kg for the uprights 27kg for the cross-pieces = 73.8kg for 100ft of ladder (at sea level) which works to a cube balloon of 4.5 metres-ish on a side, which doesn't seem that immense. |
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// if you are talking about satellites that send TV signals for your house |
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What for? I don't have a tv. |
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I was just going for LEO, "low Earth orbit (LEO) is generally defined as an orbit below an altitude of approximately 2,000 kilometers (1,200 mi)". So, I can cut that 1,500 miles down by 300 miles.. |
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No, you have to cut it down to 30 miles. There's no LTA lift
above that. |
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As was said, an ion drive can't even hold itself up. Even for a second. |
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But no rocket can hold itself up for long. It just doesn't work that way. |
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See, if you want a rocket to hover for any amount of time, you need to add fuel enough for that time. Then you need more rocket to hold up that fuel, and more fuel for that rocket, and more ... it goes to hell fast. (Rockets need to climb as fast as possible to reduce the amount of time they spend fighting gravity---they just need to get gone, and damn your squishiness.) |
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If you want a rocket-supported ladder, you need a fuel line going up, and rockets to hold up the line, the fuel and the pumps. Ion drives get the most use out of their fuel mass, but they'll need an electric line as well, and their fuel is often a powder. |
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//Then you need more rocket to hold up that fuel, and more fuel for that rocket, and more |
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Unless you're using hydrogen and oxygen in gaseous form, in feed lines that would take care of the first 30 miles. After that, I'm still not sure about whether the gases would need to be pumped...hmmm...working on it.. |
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I took this as sarcastic and ignored it, but now
that there's an attempt to defend the concept... |
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Uncompressed gaseous hydrogen and oxygen
aren't going to work very well for rocket fuel, the
line size is going to be way to big. Don't forget
you also need to hold up your rocket engine. And
there is no LTA for LOX and LH, which is the
preferred iteration. Of course by the time you are
pumping enough fuel to support the top section,
the simple thrust of the pumping operation is
going to completely weight down everything
below it. |
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Next problem, lateral load (wind, mostly) on any
structure of this type is going to be ridiculous. |
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Third problem, as has been mentioned, getting to
LEO with a fixed structure doesn't help, because
the satellites are flying by way to fast. You need
to get to a geostationary orbit, and that's the
22,000 miles [lurch] mentioned. |
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//Of course by the time you are pumping enough fuel to support the top section |
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I have this sneaking suspicion that it might not need to be pumped, suspect my subconscious is thinking momentum/syphon or something like that. It might be necessary to encapsulate the oxygen, then insert it into the up-pipe, using a blast of hydrogen to help it on the way up. |
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LEO? No way. I was frightened by a lion as a child. |
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// I took this as sarcastic and ignored it, but now that there's an attempt to defend the concept... |
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Sure, it's not like I have anything else to do. Even my comedy routine isn't that successful. It's as the man said "When I was young I told people I wanted to be a comedian and they laughed at me. Well, they're not laughing now..." |
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You COULD send your fuel up the pipe so fast that it supports the structure by momentum. There's a whole lot of concepts based on momentum-support. None involve liquids in pipes, it's more solid weights and maglev, but maybe you could use fuel tanks. Space fountains, they're called. |
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And no, I wasn't speaking of the section in atmo, earlier. If your ladder is 1,500 miles high, we can just ignore the fact that the first 20 or so miles might be able to be air-supported, and save tooling costs by building the entire structure the same way all the way up. (For a possible savings on one percent of the structure, you'd have to double your design work, inventory and logistics train. Just snap some streamlining around the bottom, and bracing for winds.) |
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