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Space Elevator Company Fission
Dag Maggot writes "Highlift Systems seems to be going through some turbulent times with cofounder Michael Laine leaving to form his own space elevator company LiftPort. Interestingly, Liftport pledges to be a "transparent" company, and as such have provided the full text of the original space elevator proposal which was made to NASA NIAC." We mentioned Liftport before, but the proposal is new and quite interesting.
There are some crazy design specs that people don't usually consider besides the nanotubes and the lack thereof.
1) due to the weight of the cable, it needs to be thicker at the middle and taper off at the ends - this makes the attachment of a vehicle to traverse the cable considerably more difficult
2) the growing - you can't "lower" a cable from a space station. the center of gravity must remain at the geosync point if you want to stay afloat
3) the keeping cable tensioned - this involves capturing a sizable asteroid into an orbit dangerously close to the earth (as in, genocidal proportions if shit goes wrong) - and after you anchor the cable, push it back out so it will keep tension (geosync don't work here). A fly-by capture is out of the question, and actually dragging a asteroid to our doorsteps is impossible by today's figures.
Space elevator, while cool, has a loooong road ahead of it - I am not betting my money on it (within my lifetime, anyhow). Granted I probably seem like a pesky naysayer that's keeping technology from going places - but just imagine stuff we developed WITHOUT first thinking it through; I think the nuclear stockpile on US and Russian sides definitly proves my point.
I'm all for it if they can bring the damn asteroid here SAFELY, though. (Shuttles so far has a roughly 2% failure rate - and that's two completely fatal ones - I don't want the fate of the world depending on that kind of odds)
My life in the land of the rising sun.
Well, perhaps it'll be an alternative to the generation of shuttles after the next generation, probably though it'll be one after that or even further in the future...
This space elevator idea ain't gonna happen very quicky...
Check out MKDoc a mod_perl CMS
"It is also a sick reminder to see how they could fathom using radioactive materials for power. As the decade wears on I imagine we will see plenty more of these last gasp efforts to legitimize outdated, unsafe, 20th Century technologies and mindsets."
I sure hope we'll see more... nuclear technology has advanced significantly since Chernobyl, and through research and application will advance further still in the coming years.
As for mindsets: yours is the only outdated one. Nuclear technology is a relatively recent development, and we have only seen the start of it so far. And you are already going to give up on it.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
Highlift (et al) are going a vital job - figuring out the basic technology of thie enterprise, writing the real project plan, sketching the logistics, and guestimating the construction cost. Someone (probably someone else) will have to figure out the economics of this thing - when will there be enough traffic wanting to get into space, and at what price, comparing this against the cost of the structure and figuring out when to build, where, and to what scale. Everyone in this phase has an awesome task ahead of them - the planners of the worlds great canals, bridges, tunnels, and dams all had lesser examples from which they could extrapolate - there's never been structure like the elevator, and even your minimal working model is 40 thousand miles long and costs a Dr Evil sum.
Once you get to the construction phase, then you're talking about a huge corporation with major government entanglements (as all great works of civil engineering have a big strategic impact). Canals like those at Suez and Panama were built only once there was a large volume of traffic going the long, expensive way (around the capes) which made the prospect attractive for investors. And the Chunnel and the Oresund link show that just 'cos everyone wants something doesn't mean you get it any time sooner than it becomes (kinda) economic.
Still, it'll happen, just as soon as everyone is sick of going to work in another rustly old rocket.
## W.Finlay McWalter ## http://www.mcwalter.org ##
Just a minor question
Imagine holding a bucket of water, and then you spin around. The bucket of water will be drawn away from your body, extending your arms.
Wouldn't the same thing happen to the space elevator?
-smark
>Chernobyl Nuclear Power Station accident, 1986 = 810 curies released
>(above figures from www.space4peace.com)
> I believe the next series Martian probe launches are all slated to carry fissionable materials. So we are looking at potentially poisoning the entire population of central Florida as opposed to just a couple of places like Chernobyl and Kiev. That is an order of magnitude higher. A significant improvement.
And how many curies from atmospheric nuclear testing in the 50s?
Answer: several billion which has now decayed to around 400K.
And how much was Pu-239? About 225,000, from the first link.
We've already had your famed civilization-ending release of nasties into the environment. We did it deliberately (We didn't know any better. D'oh!). And yet, we're still here.
We've learned how to make RTGs safe for re-entry so the incident of 1964 doesn't happen again. But more to the point, nuclear power is the only technology with a high enough power density to allow us to extract fuel from the Martian environment for a "Mars Direct" plan.
If you wanna see men (or even long-term surface probes/rovers) on Mars for more than a couple of weeks, it's the only way to go. You can engineer your way around the risks of RTGs. You can't engineer your way out of using 'em.
That's why they're building this space elevator thingy, see. They send the first strand up in one or two shuttles. Part of the shuttle payload is enough extra fuel to get to GEO. They unroll the strand. They send lightweight climbers up with the next strand. Now they have two strands, the climbers can carry twice as much, and iterate until you have a satisfactory number of strands emplaced.
No habitats, and the ribbon weighs startlingly little per km (something like 7.5kg, OTToMH).
Got time? Spend some of it coding or testing
They are frequently asked...
Cable width?
airplanes?
orbitology?
how they plan to lower the cable?
how they plan to connect the cable?
how payloads can actually be lifted and forces dealt with?
initial chemical-launches required?
first ribbon payloads?
space debris?
weather?
space weather?
electrical potentials?
what if the cable breaks?
environmental concerns?
safety?
how to power the lift?
etc. etc. etc.
none of these are unique questions.... they fall under "frequently asked".
Read the answers to your frequently asked questions, and they will be answered.
if you have a UNIQUE question - that should get rated a +5... but so far, no one has one of those that i've seen.
Geezuz tapdancing Krist.
(folds up soapbox, puts away megaphone)
guns kill people like spoons make Rosie O'Donnell fat.
After reading the article completely and carefully my feeling is that it is feasible accept for one small thing. They cannot provide sufficent proof that the cable can be built with accessible technology. The first step in the project should be the creation of a 50 meter cable with the properties that they say are required. If this is possible everything else is trivial (although a lot of work will still be required!) Plus it allows the testing of all other aspects of the project. I think that this would be a wonderful (and cheap) pilot project. Throw a couple hundred million at building the cable prototype. It sounds like a really good gamble. If that works everything else will just fall into place.
I've suggested using the very powerful lasers that will power the lifters to ionize columns of air around the ribbon and give the approaching stormclouds a discharge path to ground. It would also be possible to send conductive cables up into the clouds with sounding rockets, balloons, or special lifters on the ribbon to discharge the clouds. This will be necessary once a year or so because of the very low frequency of lightning storms in the area where the first elevator will be located.
Note, too, that a lightning strike would only sever the ribbon very near the bottom, no more than 30-50 km up. That's a very low impact accident; the rest of the ribbon will remain in place or drift higher and to the east over a period of days. We can just move part of the counterweight a bit further out and the severed end will come back down to the surface and can be re-attached.
It's also important to note that there will be several ribbons very quickly, and many ribbons over time; a single one being cut won't be a big deal.