Space elevator ride may kill humans due to ionizing radiation
By Cyrus Farivar 
posted November 14th 2006 6:31PM
posted November 14th 2006 6:31PM
While Konstantin Tsiolkovsky and Arthur C. Clarke have popularized the idea of a space elevator, there are still a few kinks that need to be worked out before we start having folks hit the "door close" button for a 100,000 kilometer (62,000 miles) ride. The latest problem, according to a new article in Acta Astronautica (we've really been meaning to renew our subscription), is that a space elevator would be so slow-moving (200 kph, or 124 mph) that the half-week spent in the Van Allen radiation belt would kill any living thing without proper shielding. The radiation belt, which contains "two concentric rings of charged particles trapped by Earth's magnetic fields" doesn't affect current astronauts going to and from space because they are moving too fast to be hit by the radiation. Still, Anders Jorgensen, one of the authors of the study, doesn't think that this 62,000 mile-high problem is insurmountable: "I'm confident that we can solve it, but it's going to make things a little more complicated and a little more expensive." We appreciate your reach-for-the-skies attitude Mr. Jorgensen, but isn't protecting people from dying more than just a "little" complicated? [Via Slashdot]
I'm reading this post while sitting in Van Allen Hall at The University of Iowa... in class... pretending to learn... while catching up on my PS3 news.
Look like i won't be living up to the old U of I prof's expectations for higher learning this semester. Oh well.
Let somebody else figure out how to get me to the moon.
I just want to play GTA in High Def.
Slacker. I've been writing an essay all day. While on engadget *and* facebook. Multi-task, man!
To keep this on-topic: so basically we'd need to be strapped into a capsule-esque lift with jets attached...which kinda ruins the point. (Unless you get a huge weight going down, I suppose!)
In keeping with the model of slacking, I am supposed to be doing two physics lab reports and studying for two exams, instead I am browsing engadget and updating linux to ubuntu 6.10...
This is a bit of a non-issue. A space elevator needs to take people to a waiting space station below the Van Allen belts. Then they can be trasnferred to a space ship to take them further. Building an elevetor further up than low earth orbit would be impractical anyway and not neccessary as the really difficult work for a rocket is done in where the Earth's gravitational field is strongest (ie getting from the ground to LEO)
You do realize Fred that you can't built a Space Elevator to anywhere other than a Geostationary orbit? Which is on the OTHER side of the Van Allen altitude-wise. The reason is the station cannot be moving relative to the surface of the earth, otherwise you'll get some serious wind resistance issues on the surface (not to mention a hard time getting in the elevator).
I think what Fred was trying to say is the elevator is built to Geo, but you simply detach at LEO and use a small conventional rocket to get wherever else you need.
You're not REQUIRED to go the full distance on the elevator.
Not a problem.
"The space elevator would run through the Van Allen belts. This is not a problem for most freight, but the amount of time a climber spends in this region would cause radiation poisoning to any unshielded human or other living things.
Some people speculate that passengers and other living things will continue to travel by high-speed rocket, while the space elevator hauls bulk cargo. Research into lightweight shielding and techniques for clearing out the belts is underway.
More conventional and faster atmospheric reentry techniques such as aerobraking might be employed on the way down to minimize radiation exposure. De-orbit burns use relatively little fuel and are cheap.
An obvious option would be for the elevator to carry shielding to protect passengers, though this would reduce its overall capacity, of course. Alternatively, the shielding itself could in some cases consist of useful payload, for example food, water, fuel or construction/maintenance materials, and no additional shielding costs are then incurred on the way up.
To shield passengers from the radiation in the Van Allen belt, perhaps counter-intuitively, material composed of light elements should be used, as opposed to lead shielding. In fact, high energy electrons in the Van Allen belts produce dangerous X-rays when they strike atoms of heavy elements. This is known as bremsstrahlung, or braking radiation. Materials containing great amounts of hydrogen, such as water or (lightweight) plastics such as polyethylene and lighter metals such as aluminum are better than heavier ones such as lead for preventing this secondary radiation. Such light-element shielding, if it were strong enough to protect against the Van Allen particle radiation, would also provide adequate protection against X-ray radiation coming from the sun during solar flares and coronal mass ejection events."
http://en.wikipedia.org/wiki/Space_elevator#Van_Allen_Belts
I'm sorry, but this is just a terrible, inflammatory headline. No one is going to build and sell tickets to a space elevator that kills people. I guess "More Shielding Research Needed for Space Elevator" just isn't sexy enough.
Also, Engadget, sorry.. you've got it backwards. Slashdot is supposed to post two day old Engadget articles, not the other way around.
So...
Space elevator also counts as a gadget?
wow, that's refreshing.
Yes lyl545646, Space Elevator is a "gadget". That's because our next generation of scientists (and editors, for that matter) are "pretending to learn".
Shoot em up there faster.
"Let somebody else figure out how to get me to the moon.
I just want to play GTA in High Def."
And this is why video games will destroy modern civilization.
No space radiation will not games.
The Space Elevator is more for frieght..,.and not people. But it will be evuentually for people, But people probably will have no need to go out that far...think about it. For instance, the ISS is around 250 miles up...you would still be pretected by the earths magnetic field, and it would take a mere 2 hours to reach your destination.
"moving too fast to be hit by the radiation"
Pardon? Perhaps you meant "moving too fast to be hit by significant amounts of radiation".
Also, compared to the complexity of building a space elevator in the first place, adding a some shielding is pretty "little".
Time, distance and shielding
That is how you protect people from radiation. Reduce the stay time, increase your distance from thesource, or put shielding: lead for gama radiation between you and the source.
I don't think anyone can outrun a gamma, but traveling fast would reduce the stay time.
One theory is that we would send a family of scientists up there and see if they gain any special superpowers. Just make sure no Latverians go with them.
OK... 62,000 miles @ 124 mph = 21 days travel time. Who the hell is going to spend 3 weeks in an elevator??? Absolute insanity.
my thoughts exactly...who's going to spend that long in an elevator? hope they're not claustrophobic. =)
only question i have is...where the heck is this thing going? the moon?
how about that new aero-gel technology. i heard they use that to catch radiation particles or something like that. .. ok what do you want .. im a technology motivated architect .. what do i know about radiation lol .. but seriously .. the aerogel or some form of it might work????
Aerogel wouldn't work. I'm pretty sure its the least dense material ever created. Bad for stopping gamma.
"We appreciate your reach-for-the-skies attitude Mr. Jorgensen, but isn't protecting people from dying more than just a "little" complicated?"
props for dumbest ending in an engadget article.
for the benefit of the redneck editor, you should know esp given the overall complexity of the project building a radiation shield for the van allen belt is only of 'little' complexity.
hear hear.
"important" isn't the same thing as "complex," as it turns out. You'd think a writer for engadget might know that. I suspect he does, but wanted something snappy to close with. Alas, it turned out, as you say, just silly.
It's unfortunate too... I like space elevators and bad articles only reinforce people's bad (and wrong) opinions of them.
Also, people, just because it's called an "elevator" doesn't mean it's the same size as the one in your office building. Sheesh. You might arrive at that conclusion through mere logical analysis if you weren't too busy searching for every last scrap of information on the PS3 or Wii.
I think the whole idea of a space "elevator" is completely moronic. Do people really think that this would be practical or useful at all? A space elevator? Really?
Wonderer - completely agree with you, why is anybody wasting their time and money on such a thing. A 62,000 mile journey in an elevator, sounds to me a punchline to a joke.
Well.... It's cheap. Cheap-er, anyway. An elevator to a station, and from the station to... err, beyond.
Gosh, I don't know, maybe it's the prospect reducing the cost of putting objects into orbit by 3 or 4 orders of magnitude -- that's powers of ten, by the way, so, 1000 or 10000 times cheaper.
Yes, I'm being pedantic on purpose, because your "argument" invites such derision. Pushing the limits of our technological capacity is what humans do; it's why we have nice things these days like trains and cars and computers. There's nothing patently absurd about a space elevator, any more than there is with strapping a million tons of explosive fuel to your ass and lighting it.
I'm not saying it's the only game in town, and I'm certainly not of the mind that there are no problems with the idea, but your dismissiveness is just lazy.
On top of which, even if the space elevator never comes to be, big goals like this generally produce a whole lot of smaller achievements along the way, which tend to be readily adaptable to products. As a simple example, the SE folks are learning a lot about how to handle carbon nanotubes from the standpoint of fabrication, embedding them in substrate, safety issues, etc. That work is likely to produce valuable applications completely separate from the SE. I guess better flak jackets and high conductivity wires and stronger cables for building bridges and so forth are laughable too.
A space "elevator" in the traditional sense (hoists/pulleys/counterweights/etc.) WOULD be completely moronoic; calling it such is in fact a misnomer. A more accurate name would a space "cable" because that's all it is: a super-strong cable stretching from the equator halfway to the moon. Centripetal force keeps it taut (think bucket with water being swung overhead) while a climber ascends with power beamed from the surface. It's possible, if technically challenging, and would be amazingly useful because it would drastically drop the cost of going into space.
Wow props for first non-moronic comment in the thread. congrats.
Did we misplace a decimal point?
Space is generally defined as 100km or 100,000m not 100,000km. Remember the SpaceshipOne X-prize?
So the elevator ride would only be about 30min. Not so bad unless you die from the radiation.
Yes but you aren't just going to space, you are going to the spot where Earth's gravity no longer affects you very much...Sorry, but you lose.
Instead of an "if" statement a mile long that leads to a possible multi-trillion dollar 'space elevator', shouldn't these scientists, or should I say sci-fi-intists, devote their energies to something somewhat realistic? There are hundreds of real world technologies that need improving, including water desalinization, cleaner nuclear or fusion power, fuel cell technologies, etc. You know, things that could make the world a better place.
I swear if I see another "space elevator" headline.
fantastic 4 FTW!
This news blurb is idiotic. Inflammatory headline. Stupid, non-sensical, inflammatory concluding sentence.
Protecting people is a "little" complicated if the threat to the people is not hard to overcome.
I'm thinking.....time to develop shields? :)
What will space-elevator music sound like?
Heh heh, radiation.
Just because the space elevator structure extends to a certain height in space to make it "balance" doesn't mean that we have to send people/cargo to that height! We would have one (or more) intermediate landings for various purposes, with the final landing WAY below the top of the structure, thus avoiding the radiation belt.
We appreciate your reach-for-the-skies attitude Mr. Jorgensen, but isn’t protecting people from dying more than just a “little” complicated?
I am not he, but I can answer. In this case ‘no, not really’. We (speaking as a culture) have known ‘how’ to protect people against radiation for going on oh, sixty years now.
You wrap the passenger compartment with tanks of water. Water stops radiation. Water can also be re-used at the top or stored against need.
wouldn't earth's orbit be a problem?