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NASA Still Wants Space Elevator
Jerry Smith writes "The Guardian reports 'Each of the groups that will gather in New Mexico is competing to win a NASA prize set up to encourage entrepreneurs to start development work on the technology needed to create a space elevator.' It still might take a while though, progress is slow, so slow."
when a plane runs into the elevator? It only takes one crazy pilot.
I know a man named Otis who invented a room,
And his heart was filled with pride.
I said to Mr. Otis, "What does your room do?"
He said, "It goes from side to side."
So I said, "Mr. Otis, if you take my advice,
You'll be the richest man in place.
You gotta take that room that goes from side to side,
And make it go to outer space."
And that was good advice, good advice.
Good advice costs nothing, and it may win a prize.
NASA offered me
Four-hundred-thousand dollars, whee!
For good advice.
Have you read my journal today?
It still might take a while though, progress is slow, so slow.
There is of course truth in that statement, especially considering the effective infancy of CNT materials science. Many gains have been made in the past 15 years or so, but it takes time...and thus the quote from the summary. We are today seemingly obsessed with instancy; however, this is to our detriment. Patience, patience!
They won't waste time and resources to create a folly, this principle is a worthwhile venture (if it can be pulled off).
Once you get one tether you can send runners down it with additional strands.
It would be strengthened and grow like a pearl from an initial seed.
The problem is getting that seed line up there.
liqbase
The same technologies used to build a space elevator from earth would be usable for building other things: space elevators for other planets, for one, since every body in the system that could use a space elevator has a shallower gravity well than Earth; inter-orbital elevators; rotating tether slingshots; ...
If they want a space elevator, they'll have to earn it the old fashioned way: buy enough candy bars to get a golden ticket, and by all means RESIST all temptation to snack on that scrum-diddly-umptious confectionary cornucopia when touring the factory.
Where were you when the voynix came?
If we are some day able to create this elevator, the distance involved means it will take several days to complete a journey from ground to earth orbit.
I have a hard enough time avoiding contact with "other people" in elevator cars -- but the real tragedy will be the music. Girl from Impenema for 72 hours straight?
Aaaraargh.
The only way I could see this working is if they piped in aerosol (-)-delta9-trans-Tetrahydrocannabinol and phillip glass...
In geostationary orbit, a LED ZEPPELIN will be holding up this STAIRWAY TO HEAVEN. They will probably outsource much of the work to KASHMIR. I hope the isn't a COMMUNICATION BREAKDOWN that makes the whole thing come crashing down OVER THE HILLS AND FAR AWAY.
How ya like dat?
Don't forget GPS. And satellite TV. And high-speed intercontinental data backbones. And weather forecasts based on satellite imagery. Even 'failed' missions such as Beagle 2 resulted in significant scientific advances (in that particular case, reducing the size of a mass spectrometer from the size of two desks to something the size of a Kirk-era tricorder prop).
"Tornado's, earthquakes, hurricanes, flooding... Mother nature probably poses a very large threat to this thing"
History shows again and again how nature points up the folly of man. You know that once Godzilla gets a bus caught between two gargantuan fangs that he just can't pick out with his silly T-Rex claws, he's going to be looking for some good dental floss.....
Where were you when the voynix came?
Try reading 'Fountains of Paradise' to understand the scale at which the space elevator is envisioned. It's not an elevator in the sense you may be thinking of. The idea is to build an initial small elevator, and then use that elevator to lift extra mass onto the elevator itself, and to build up its size until it's a megastructure. The goal isn't to build an elevator with a single shaft that can handle 10 people at a time. The goal is more like having a vertical subway system that can handle a million passengers *per day*. Think of the New York City subway system... only vertical. *Thats* the long term dream/goal of people who are into the concept of the space elevator.
It's true that we may never see a space elevator -- it's entirely possible that the engineering problems involved in deploying one a simply beyond our ability to solve. But assuming for the sake of discussion that it is possible to deploy one, then there's no question that it would be an order of magnitude more useful than any imaginable rocket-based delivery system. Rockets are a good (if risky) way to get small amounts of material into orbit, but they completely fail to scale up past a certain size. The reason for that is because they have to carry their fuel up into space with them.... the more mass the payload has, the more fuel it has to carry, and the real killer is that you also have to carry more extra fuel to lift the extra fuel. So as the mass of your payload increases linearly, the mass of the fuel you'll need to launch it increases exponentially. At some point there simply isn't enough money in any nation's budget to acquire the amount of fuel they would need (never mind building a rocket big enough to hold it all).
That's why (barring the invention of some near-massless rocket fuel) you'll never see massive amounts infrastructure being lifted into space on rockets. With the space elevator, on the other hand, the problem is neatly bypassed: the elevator "car" carries no fuel at all. Instead, the energy needed for lift is beamed to photo cells on the bottom of the car via ground-based lasers. If you want more lifting power, you simply point another (or a bigger) laser at the bottom of the car... there is no exponential increase in fuel requirements, just more equipment (and more power consumption) back on the ground.
So yes, rockets can get us a nice little "lift the rich tourist into low-Earth-orbit for a few days" industry. But if you want to do Big Stuff, like large spaceships capable of carrying a crew to Mars and back, or solar power satellites, then you'll either need a Space Elevator to bulk-lift all that mass, or some way of finding pre-existing mass already in space and building all the components there.
I don't care if it's 90,000 hectares. That lake was not my doing.
I have been following this for some time... Here are a few links for ya.l Study
http://www.isr.us/Downloads/niac_pdf/contents.htm
LiftPort Group. Company wants to beat NASA.
Reference Site
Place a curse on the RIAA/MPAA
In terms of energy losses, the elevators are generally accepted to be more effecient (admittedly this is theoretical).
It takes enourmous amounts of energy to put anything in orbit. Period. Future technology, in whatever form it takes, will face the same physical limits.
Rocket fuels aren't cheap, and aren't going to get cheaper. Moreover, rockets have a very low weight limit - those commercial launches you mention put up tiny satellites, and even then they cost through the nose.
Show me the advanced launch tech that can put something heavy in orbit today. Oh, right, it's that model of effeciency the space shuttle. Trust me, if that's the cost per pound that a space elevator has to beat, we could make it out of pure gold and still come out ahead.
We don't have anything that can do what a space elevator can. Unless you can show me an example of a launch system (existing or theoretical) that can carry the same weight, then your arguement that "by the time we can build the space elevator, we'll have better tech", is invalid. Seriously, go take a look at stuff like the X-prize craft - these are the "spaceships of tommorow" and they still carry very little payload, to no higher than LEO, for a hefty price.
Erotic is when you use a feather. Exotic is when you use the whole chicken.
The SE is a rock on the end of a very, very long string, being whirled around by the Earth's rotation. That's what keeps it up -- what's sometimes called centrifugal force. Pulling inward/downward on the string doesn't cause the rock to fall; if the rock is whirling fast enough, it won't even be pulled down, and when you stop pulling, the rock is still there. There's no real notion of "center of mass" of the SE as a whole. The majority of the mass is well above GEO.
The "rock" will actually be all the construction machinery that was used to build the SE, a few hundred machines that climb it and add a tiny bit of material all along its length while they're going up. They will have a total mass of about 650 tons and be at an altitude of 100,000 km. The CNT ribbon will have a mass of about 950 tons. We'll be able to send up a 20-ton climber with a 13-ton payload every four days, or a 10-ton climber with a 6.5-ton payload every day. (Gravity falls off so quickly that a given climber is down to 50% of its weight when it's 2600 km up. That's what makes it possible to send up smaller climbers more often than you'd expect.)
If you accelerate something to escape velocity, it does exactly that: escapes the gravitational attraction of the Earth and never comes back, unless it's decelerated by some unspecified means. And escape velocity at 11km height means it will be burned to ashes very quickly, remember the Columbia. With our current technology level, building a ship that can fly at escape velocity at 11km height is much more difficult than building a space elevator.
OTOH, if you want to put something in orbit around the Earth, then you should give it orbital velocity, which means it should have a very high tangential velocity around the Earth. You cannot do that with a vertical tower, unless that tower reaches the synchronous orbit altitude of 36000km, which is the whole idea of a space elevator. Remember, velocity is a vector. It has both magnitude and direction. If you want to reach orbit, it's useless to throw something straight up with a high speed, because it will fall straight down.
Well, you may say, let's make the top of the tower curved, so the ship will be accelerated tangentially. Do the math. Find out how big the curvature radius must be so that the ship isn't subjected to deadly accelerations in order to convert that vertical velocity to orbital, i.e. tangential, velocity. That math has been done even before artificial satellites reached orbit. I have an old book, "Flight in Cosmic Space", written in 1952 by Russian scientist Ari Sternfeld, where he analyzes, among other concepts, the idea you have proposed. A practical accelerator to send a ship into space would have to reach a 100km height and have a curvature radius so great that it would be several thousands kilometers in length.
The laws of physics work just as well for any nation.
I am convinced that Man will conquer space. Whether the dominant language is American-accented English, Mandarin, Spanish or Japanese is still uncertain, but your capability remains.
You have a brilliant track record, and a wonderful people. Your achievements have inspired me to a thousand times greater use of my potential, my career, than I would have ever reached without them.
However, from across the Pacific it looks like you're in a kind of perpetual Saturday afternoon over there. Might I diffidently suggest that you, as a country, get up off your arses and start doing what you were best known for again? Your beer is terrible, your automobiles are awful, your cuisine apalling, and your politicians are worse than the French.
But your aerospace engineering is utterly superb, and the hope of the race. Don't let the rest of us down.
Do not mock my vision of impractical footwear