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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."
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
when a plane runs into the elevator? It only takes one crazy pilot.
That's where the frickin' laser beams come in.
Most likely, the cable would break, the 99.999% of the cable above the impact point would start to drift upwards, and the 0.001% of the cable below the impact point would fall harmlessly to earth. It would then be a bit of a chore to repair the cable, but not impossible. Fortunately this wouldn't happen, because the cable's base station would be located somewhere in the middle of the Pacific ocean, in the middle of a no-fly zone several thousand miles in diameter. For a crazy pilot to get to the site of the cable, they'd have do evade detection by radar for several hours, and avoid getting shot down by the SAMs or military aircraft whose sole job is to guard the cable against this sort of attack.
Now a question for you: What happens when a plane runs into the Space Shuttle during launch? It only takes on crazy pilot.
I don't care if it's 90,000 hectares. That lake was not my doing.
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...
I was going to pick on your math for the 99.999% thing, but that's actually decently accurate (at least according to the article). I thought satellites were much much closer to earth (600ish miles) but after a little research I found out those are the asynchronous orbit ones. For true geosynchronous orbit you need an altitude of 22,223 miles. Roughly 1/10th the distance to the moon! Space is a wee bit bigger than I thoguht ;-)
. isn't that a significant portion of the earth (neighborhood of 1% of the surface area)? Maybe I'm just tired, but these differences in scale are just insanely hard to get my head around.
The one thing that does seem far-fetched is the several-thousand-mile-diameter-no-fly-zone-idea..
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.