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Space Elevator Gets FAA Clearance
lonesome phreak writes "Techzonez has a short piece about the recent FAA waiver received by the LiftPort Group allowing them to conduct preliminary tests or their high altitude robotic lifters. The lifters are early prototypes of the technology that the company is developing for use in its commercial space elevator to ferry cargo back and forth into space."
But would we be able to hold miles of it together, without anything going wrong? That's the challenge.
That, and the money needed to build and maintain it.
It could become a terrorist target.
Sigh, could you please shut up about terrorist threats? What makes a space elevator more a threat than a space shuttle, or a Golden Gate bridge? BTW: space shuttles are full of highly explosive fuels!
This is a good moment to ask yourself if you're not affected by propaganda too much..
"It's too bad that stupidity isn't painful." - Anton LaVey
Oh, c'mon - the grandparent here must be bollocks... an unqualified ridiculous statement.
/me hums a song about Cuba.
By that logic, a US citizen, couldn't come to say, the UK, get a CAA issued license and fly with it coz they don't have permission from the FAA?
I know the Seppo's have been going a bit nuts lately, but, how do you imagine they'd enforce these sort of rules, arrest folks on re-entry into the US?
I have no idea why
Why start investing in a project when you don't even know if you will legally be able to do it? Get approval first.
Uh, no? Geosynchronous/geostationary orbit means that the whole thing will rotate at the same speed as the point it's attached to. Besides, think about what you just said. Man-made structures are infinitesimal against the scale of an entire planet. I don't have numbers on it, but rest assured that even a big space station with a tether going all the way down to the surface of the planet would not have anything close to the mass needed to exert any real force against Earth's rotation.
Sorry, my karma just ran over your dogma.
Not sure about Perpetual Motion & Duke Nukem Forever, but ...oh come on. That'll never happen. It's far more likely that SCO will beat IBM than that ever happening.
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If you take that section in context instead of just reading it itself, you would find that the problem was not that they built a tower, but their motives for building it. They wanted to get closer to God. Theres nothing wrong with that except for when you do it outside of how he tells us to. He didn't tell us to build a tower to him to get to him, he told us to let him come to us. He was disgusted with the Babylonians because of their pride, not because of their tower building prowess.
Of course, there's a massive waste of time, effort and money in the meantime. And who is to say that by the time this "space elevator" comes around and is usable to launch space vehicles, we won't have developed a more efficient, cheap, powerful fuel to launch shuttles?
It's like high power computing. Sometimes waiting is the best solution. You could start computing in 1980 with whatever power is available and it could take - what - 30 years for the computing to finish on that power? Or we could wait until 2005, toss a couple of cheap boxes together and achieve the same computing in a few months - coming out ahead of if we had just started in 1980. Saving time, power and money.
I don't think we'd ever use the elevator. At best, it'd just be a technology that comes and goes without being useful to anyone - except that in the process of creating and building it, we'd probably have acquired some useful degree of scientific discovery and experience that would help with future endeavors in other areas... The question is, will what we gain from it be worth the money invested in it?
By that logic, a US citizen, couldn't come to say, the UK, get a CAA issued license and fly with it coz they don't have permission from the FAA?
I believe it only applies to US-registered planes, not US citizens... Since the plane is registered in the US, anything that happens aboard is under US law, including actually flying the thing.
At least, that's how I understand it works here in Australia. You can't fly Australian-registered planes with a US licence, but you can fly US planes within Australian airspace with a US licence.
"Go to CNN [for a] spell-checked, fact-checked summary" -- CmdrTaco
God has a tantrum because human beings are attempting to do something other than slaughter mindlessly in his name. Here, we see people attempting to accomplish a feat of engineering. In reprisal, God thwarts the effort by rewiring their brains to inhibit communication. This leads to the formation of diverse cultures and perspectives, which in turn leads to ignorance and intolerance in many cases. As a direct result, human kind engages in mindless slaughter in God's name.
Eventually, however, our species ends up creating much taller towers a thousand years later anyway... Which people then destroy, causing mindless slaugher in the name of God.
God is stupid.
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While I agree with your response in principal, your example of the flying cars is a poor choice.
The difficulties with flying cars aren't rooted so much in technology (fuel source) but rather in the inherent problems created revolving around traffic monitoring/control, the necessity for a pilot's license, the stupidity of the average driver, reduced control leading to an increased number of collisions, issues of collateral damage from an accident/auto-failure, the drastically increased mortality rate for such incidents, etc.
The problem of finding a cost-effective fuel source is almost a moot point as nobody would vote to allow people to fly over their houses/cars with them with all of the potential complications. The concept of the everyday man zooming around in a flying car is a grand concept of the future planted in our minds by fantastical books and movies, but it isn't really a realistic notion in today's civilized society.
A fuel capable of launching payload in rockets as cheaply as an elevator could launch it is almost inconceivable in the next 50 years. There are simple physics arguments that rule out any chemical propellant, there just aren't chemicals with that much energy per kilogram locked up in them. Even nuclear-thermal rockets that use any kind of material nozzle or containment system for the nuclear reaction simply can't be efficient enough -- the maximum temperature of the exhaust (limited by the nozzle) will only force hydrogen out so fast. A magnetically confined nuclear rocket could work, but the closest thing we have to a magnetically confined nuclear reactor (JET) weighs hundreds of tons (at least) and still produced less power than it takes to run the magnets.
In this case, the elevator seems like the right solution. All forms of rocket suffer from having to accelerate the engine (and some of the fuel) to orbital velocities. In an elevator setup the engine is a power station (or grid connection) on the ground and never goes anywhere.
Coriolis effect would happen precisely _because_ it's at the equator and perpendicular to the ground, and precisely _because_ it shares the Earth's rotation. The only places where you wouldn't get that, would be the poles. (But then good luck keeping anything in a geostationary orbit above one of the poles.)
The problem is that you're moving from a smaller radius R1 to a larger radius R2. If you tried keeping the same angular velocity (and precisely because it's perpendicular to the ground, it is getting constant angular velocity), the linear velocity is the radius multiplied by the angular velocity. It's that linear a progression: twice the radius means twice the speed. So in the first place you have a smaller speed v1, and in the second you have a larger speed v2.
To get that, which is the pre-requisite to having it move in a straight line upwards there, you have to apply some extra force (e.g., horizontal thrusters) to increase the speed. If you don't, it will fall behind. That's Coriolis effect in a nutshell: the object's tendency to lag behind as you move away from the centre, or to gain angular velocity as you move towards the centre.
Why it happens on Earth? Because Earth is a sphere. As you go from either pole towards the equator, the radius increases. To move in a straight line from N to S in the northern hemisphere, you move from a small radius to a large radius, at constant angular velocity. (If you stay along the same meridian, you do a full circle in exactly 24 hours at any point along it.)
That means you need to gain speed to stay on that same meridian. While both a city in Canada and one in Mexico have the same angular velocity (both do a full circle in 24 hours), the one in Mexico moves faster horizontally. It moves more feet per second towards the east than the one in Canada.
If you tried launching an ICBM from Canada against Mexico, you couldn't just point it straight to the south. If you did, it would fall behind and fall into the Pacific. You'd have to aim it a bit to the East, so it gains that speed difference by the time it reaches Mexico.
That's Coriolis effect in a nutshell.
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