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Space Elevators Could Be Lethal
Maggie McKee writes, "A new study reports that passengers on space elevators of current design could be killed by radiation. Even traveling at 200 kilometers per hour, passengers would spend several days in the Van Allen radiation belts, long enough to kill them." Looks like the elevator scientists will get this one solved before liftoff.
will tinfoil hats help?
One of the most popular (and massive) items that will need to be shipped to orbit will be water; and water makes a good shield against radiation. Just make your passenger cars with a living unit inside a larger freight unit, and fill the gap in between with water. If you used filtered fresh water you could even have windows on both walls and be able to look through.
From TA: "it's going to make things a little more complicated and a little more expensive"
Everybody panic! Apparently, "a little more expensive" == "potentially lethal"!
I guess people should buy from Wal Mart instead of Target, since the latter is "a little more expensive". Obviously making a purchase at Target will kill you. I love sensationalist headlines.
Mutant Freaks of Nature: "Frighteningly Addictive"
I thought the main idea was to send equipment, not people? If we can get one in place (which doesn't seem particularly likely any time soon), it'd be far cheaper to send tons of heavy stuff into orbit via a tether than via a rocket.
$x='S24;r)>63/* h@<5+oZ)32"5cz';$me='phroggy'x$];
$x=~y+ -xz+\0-Tx+;print$_^chop$me for split'',$x;
This is why the First Amendment is so important- to expose Corporate Greed! Greed which led space elevator manufacturers to produce elevators without the neccesary safety precautions. How many people have to DIE in the name of profit? How long will it be before space elevator travel is actually made safe? It should have been done BEFORE the elevators were even built, damnit!!
Thank you Maggie McKee, for planting a seed for the grassroots "Space Elevator Safety" movement!!
How much thrust would a rocket need to zip you through those sections if you waited to fire it until reaching, say, 500 - 800km? Surely by then you'd be far enough away from Earth that a little bit of push would go a long ways, compared to firing a rocket from the ground?
Unpleasantries.
The article says that you may not want to add shielding because of the added mass. Wikipedia says that "an object satellite shielded by 3 mm of aluminum will receive about 2500 rem (25 Sv) per year." I don't know how this would translate for people going through the area, but 3 mm of aluminum doesn't weigh much.
This post climbed Mt. Washington.
So can regular ones. Your point?
The solution, of course, is more speed! With a mass driver, and 1000+ Gs acceleration, you too can zip right through that hazardous Van Allen belt in record time!
You quitting proves that the karma kap worked. The most annoying of the whores shut up. --CmdrTaco
Additionally, the space elevator is expected to be very tall, taking riders several miles above the surface of the earth where, experts say, they could fall to a harrowing death. And if that's not bad enough -- it turns out that if the earth were to suddenly stop spinning, the entire space elevator could come crashing back down to the ground!!! I, for one, will from now on refer to them only as "Space Elevators of Death!" in order to raise awareness about this potentially leathal issue!
https://www.eff.org/https-everywhere
Sure, just eat at McD's for a month, and you'll go through all your belts in that timeframe. Supersize me!
MadCow.
I used to have a sig, but I set it free and it never came back.
"Yeah - Like China will build a 4000 mile long wall."
"Yeah - We are going to build a tunnel under the English Channel."
"Yeah - We are going to dig a ditch to let boats cross America."
"Yeah - The Egyptians are going to build a gigantic pyramid that will still be standing in 4500 years."
"Yeah - We will propel a highly explosive cargo ship to the moon carrying people."
CS: It is all sink or swim...oh and did I mention there are sharks in that water?
Given that gravity won't be nearly as much of an issue at that altitude, a combination of shielding including water or metal (likely both) and increased speed seems to me to be the simplest route. All things being equal, that's probably the better solution.
We've made it through the Van Allens before, we'll figure out how to do it again.
And, anything can kill you, really, so long as it's an action. Space elevators aren't lethal in and of themselves. Organ failure due to blunt trauma, rapid depressurization, radiation poisoning; these can kill you. An elevator cannot. It's an inanimate object. Well, unless you're on acid. Then you're on your own, kid.
If all my base are belong to you and I attempt to retrieve my base, does that mean I'm freebasing?
Everyone knows exposure to this radiation is nearly always benign...in fact, 75% of the people exposed to this radiation found it to be beneficial. The remaining 25% were less pleased, apparently having super-strength and near invulnerability does not make up for the fact that one's body is covered with rocks and people call you a "Thing."
My other sig is extremely clever...
If you eat the pizza you destroy your shield!
And just where do you think you're going to get pizza for the return journey. No, my friend, these are critical protective pizzas, not for eating. In space, there are no wood-burning ovens. Or mozarella.
Order the pizzas frozen from Domino's so you won't be tempted to actually eat them.
the major advances in civilization are processes which all but wreck the societies in which they occur - A.N. White
To low earth orbit, yes. But remember that the cable is stationary above the Earth, so one orbit is exactly 24 hours (it's more like 90 minutes in LEO). Thus, to move fast enough to actually be in orbit, rather than just falling back down to Earth, the elevator must go all the way to geosynchronous orbit, which is more like 24,000 miles out.
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
Seriously, why humans? Get your fix riding your local space tower / space needle ride.
The problem it solves is CHEAP transport into space for cargo. NOT people. robots will be better than humans for nearly all space work. It will be a long time before we NEED human space transport.
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It's a horrid idea, and it STILL takes just as much actual energy to put anything in orbit...
No, it doesn't. Most of the energy used by a rocket goes into the exhaust's temperature and velocity, not into the payload's velocity. Better yet, much of the energy that goes into a space elevator payload comes from the Earth's angular momentum, not from the beamed power source.
You're right that laser launch may be a good idea, and you're right that the materials necessary to build a geosynchronous tether on Earth do not exist in bulk and may never be good enough... but there's obviously still a gap between the amount of passion you've spent learning about both subjects and the amount you spend speaking about them. Calm down, take a deep breath, and back slowly away from the Caps Lock key...
If it just lets people off, they're going to fall straight back down to earth unless they have some way of accelerating to an extra 20,000km/h fairly quicky.
When the posters fear their moderators, there is tyranny; when the moderators fears the posters, there is liberty.
Actually, unlike other get-rich-in-space-schemes like tourism, a Space Elevator would be a major revenue generator, and not just a novelty. With the ability to safely lift tons of material into space on a daily basis, a lot of industries would become viable: mining, solar power satellites, regular interplanetary travel, zero-gravity factories, non-trivial space stations, etc. Oh yeah, tourism too.
Space right now is like the Wild West before the invention of the train. You can send a few people out there, sure, but it'll never really be settled in any non-trivial way until there is a bulk-shipping infrastructure in place.
I don't care if it's 90,000 hectares. That lake was not my doing.
Ionizing radiation is just awful on chemical bonds and crystal structures. After all, it works by knocking electrons or whole atoms loose from the nice, bound states they were in. That's how the radiation damages you, too -- it's just that biological systems are a whole lot more sensitive to being scrambled, than are bulk objects like bricks or (to pick a not-so-random example) bundles of carbon nanotubes.
High doses of radiation do strange things to materials -- increase cross-links, damage coherent structure, add skillions of crystal defects. If you lower a nice flexible, white piece of polyethelene plastic into a nuclear reactor for a while, you are liable to pull out a yellow, harder, brittle, fragile piece that has the same overall shape.
If I understand the nature of the space elevator right, each particle "hit" would tear apart a carbon nanotube, gradually shortening the average tube length and weakening the whole bulk structure. I'm sure someone has thought of this effect, but we haven't seen much of it in the space elevator press packets.
Why would I travel at only 200KPH? How about 2000Km:h, on an engineered track, through the near-vacuum past 100-200Km out? Space is an acceleration game, so really I'm concerned only with how long I have to spend under the crush. At 1G, I could get to 2Mm:h (Megameters per hour) in under 1 minute. 15 minutes through the atmosphere, another minute up to 2Mm:h, then a couple of hours to the top (another 1.5G deceleration for a minute) once friction is immaterial. At 1.5G all the way up halfway, then slowing 1.5G the rest of the way, that's 2 minutes to the top. I don't know if I'd want to fry on a daily commute, but why live with Earth limits when we're leaving the Earth?
The other solution they're not considering in that article is to engineer the elevator car to travel inside the cable, rather than outside. Use the mass necessary for tensile strength for radiation shielding, too.
These are 30 second solutions. I'm sure the next decades before we actually deploy the spacehooks will find lots of better solutions.
--
make install -not war
I don't think you've thought it through. Of course angular momentum isn't free, but that doesn't mean that you have to send things down the cable to keep the elevator from deorbiting. Once a unit of payload mass is lifted past the center of gravity of the cable, it effectively becomes part of the counterweight, increasing the amount of mass the space elevator is capable of lifting from then on (up to the point where the increased tension would cause the cable to snap, anyway).
So where does the "non-free" angular momentum come from? From the angular momentum of the Earth, of course... every time something goes up the elevator, the Earth spins a tiny bit slower -- similar to how an ice skater spins more slowly after she extends her arms. Fortunately, the Earth is massive enough compared to us humans that we'd never conceivably make a noticeable dent in Earth's momentum reserves (famous last words?
That said, a second parallel "down" elevator near the "up" elevator might be useful at some point, for more efficient round trips. But that's for later, the first task is to get a one-way elevator working.
I don't care if it's 90,000 hectares. That lake was not my doing.
... Or given SUPERPOWERS!
You guys can't fool me, I saw that documentary about those people on the space station. I wanna be the one who can be all stretchy!
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Actually, the giant counterweight at the top of it would be actually beyond geosynchronous orbit, and the center of mass of the cable would be in geosynchronous orbit, but the cable itself would not be in any kind of orbit.
Saying the cable is in geosynchronous orbit is analogous to saying that the cables on a suspension bridge are "flying".
Random and weird software I've written.
Next hurdle to overcome: how to keep from going batshit insane while riding in an elevator for 7.5 days.
I Am My Own Worst Enemy
Perhaps if they played light, pleasant music continuously in the background, it would calm the passengers and make them think tranquil thoughts.
"I've got more toys than Teruhisa Kitahara."
"Yeah - We will propel a highly explosive cargo ship to the moon carrying people." ... "and bring them back safely to earth"... which was the hardest part.
snarkd
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