The article also mentions if the hydrogen tanks are charged from an external source, it can go as far as a conventional vehicle.
I understood that perfectly.
The big deal here is it's capable of producing it's own hydrogen/fuel, even if only a little bit at a time.
Nothing new here. The idea has been considered many times, but rejected for its low energy yield. The project is cool, but it's not groundbreaking.
If fuel stations were set up to use larger solar arrays than would fit on a car, or even power from the grid, much more fuel could be produced.
That's a very good idea. That's why I believe I included it at the end of my original post.
If I'm not mistaken, the byproduct of hydrogen combustion is water, so assuming a closed system, it would theoretically have the capability/raw material to run for a good long time.
Assuming a closed system (your car), you'd run out of water sooner than you would have run out of gasoline. Hydrogen is less energy dense than petroleum.
So long as there's a source of electricity (solar, battery, generator on bike pedals), there's the potential to refuel itself.
Agreed. The problem everyone is trying to solve is, "where can we get a constant dozen or so kilowatts of power?"
or unpack a stationary bike and pedal for a while until you have enough hydrogen to get on your way
Perfectly feasible. Your body can sustain about 200 watts of constant output (sometimes a bit more if you're in good shape). That means you should be about to get about 10 minutes of drive time in only (10,000 j * 60 seconds * 10 minutes / 200 j/s = 30,000 seconds = 500 minutes = 8.3 hours). I suggest you walk.
Or how about using an alternator to continuously generate power as the vehicle is moving?
Where do you think the power is coming from to drive the alternator? Probably the engine. The engine is powered by hydrogen. The hydrogen contains X amount of power and no more.
I know it sounds like it would work on the outset, but you just described a perpetual motion machine.:-)
No matter how many ways I try to parse your post, you're not making any sense. Allow me to explain:
The energy used by the car for propulsion is the energy already stored in the water.
No, it's stored in the hydrogen. The water is "pre-burned" hydrogen and oxygen. At a perfect conversion rate, it takes exactly as much energy to convert water to hydrogen and oxygen as you get from making hydrogen and oxygen into water.
In other words, you add energy to the system and it gets stored in a fuel form. The energy doesn't already exist in the system.
The energy from the solar panels is not the limiting factor.
Eh? Let's say we get 200 watts/m^2 of sunlight. The solar panels are only going to be ~20% efficient. That brings us down to 40 watts of energy. The electrolyzer is probably about 50% efficient, bringing our final storage rate to ~20 joules per second. That works out to about 72 kilojoules per hour. Which at a "mere" 2kw of constant use would provide exactly 36 seconds of driving time. (Actually less due to further inefficiencies.)
They'd actually get more power by storing the solar power in batteries, then using an electric drive. The only trick is that batteries tend not to be as energy dense as hydrogen.
Now, it might be true that even at perfect efficiency, you'll never get enough hydrogen from the water using solar power, but that's a different calculation that what you're doing.
What calculation am I doing? Energy is energy, and power is power. You've only got so much of it in a system, so you have to make the most of it.
Although the truck performs as planned, it's more of a demonstration project than a practical vehicle. The four solar panels and hydrogen-generating system create only enough fuel per day to travel a few miles.
And it's not going to go any farther. On an average day, you're lucky to receive about 200 watts/m2 of sun power. The rest of the energy (about 1.3kw/m2) is lost to diffusion and blockage by the atmosphere.
We've discussed this before on Slashdot, and it has been felt that Sun power could be a great "fuel saver" idea for hydrogen cars. But moving something the size of a modern car is going to require more energy than you can collect from sunlight. (IIRC, ~2 kw to cruise and 10kw to accelerate a small car.)
That being said, I applaud their efforts in the direction of alternative energy sources. Hydrogen is simply not as powerful as petroleum products, but it's pretty close. Concepts like creating fuel with a built-in electrolyzer could be the key to making hydrogen cars seem just as powerful and efficient as petroleum vehicles.
Now if they wanted to prove that hydrogen fill stations could use large Solar Power arrays to power their electrolyzer, then I'm with them all the way.:-)
That "guy" was Garth Knight, the real Knight son. (As opposed to Michael Knight who took the identity to cover his death.) The truck was called Goliath and had no AI.
According to this page they used several different models for both KITT and KARR. I think you might be right about the headlights, though. What I'm thinking about are probably the parking/fog-lights which have a different looking slit between models. Also, the front grill seems to be a bit sleeker in some models than in others.
AKAIK, it's the only high compression video codec to not be encumbered by patents. (Although I've heard whispers from the OGG/Vorbis team.) That right there makes it worth development. Once the codec reaches a stable version, it can be integrated into free player solutions like HelixPlayer and VLC.
BTW, did you ever notice how KITT changed his model throughout the series? In some episodes, he was of a model with popup headlights. In other episodes, he was a model with forward beam lights. Which one was *really* KITT?
Don't forget about the Wing Commander series which was already a movie mixed with a game. Yet they screwed even THAT up when they moved it to the big screen. What would be so horrible about taking the existing actors and doing a story set anywhere they want in the timeline? Improve the sets, effects, etc. and they would have had a pretty good movie. But no, they had to go and "re-imagine" it.
It's funny because this movie has been in the works since Doom II came out. At the time, there was a blurb in PC Gamer about how they were going to make a movie out of Doom. Then Quake came along and there was another blurb about plans having switched to a Quake movie. Now (some decade later) they're talking about a Doom movie again. And every last announcement was supposed to be "a sure thing".
The only sure thing about Hollywood is that they'll run you around in circles. Maybe we should give the movie to Bollywood. Then the grunt can get up and sing after he kills the evil cacodemon!
It would probably bounce off the atmosphere then. Remember that you are not sending the object down, you're skewing its path. Thus the object's trajectory would look a lot like a stone thrown outward toward the water. Gravity pulls the stone down, but that only serves to skew its trajectory. The result is that the stone skims the surface and bounces before it can lose enough velocity.
Remember, LEO orbital velocity is at least 9.7 kilometers per second. If your car was traveling that fast, you'd be burnt to a crisp within seconds.
You might find this article interesting. It seems that after Eisenhower's mispronunciation of "Nuclear" as "Nucular", the military took up the name as a way of distinguishing "Nucular Weapons" (Bad! Evil! Hiss!) from "Nuclear Energy" (Good! Clean! Wonderful!). Their idea is to promote nuclear power through an intentional separation of the two in the language.
Whether it's working or not is for the public to decide, but my guess is that Bush is using the term "Nucular" on purpose. Especially since he's shown that he's perfectly capable of using terms like "Nuclear Medicine".
It doesn't go down like you think. Instead its orbit flattens and it might come back and smack you when you least expect it. (Draw a circle and an elipse around a point. See where they cross? That's the problem.)
Eventually of course, everything in orbit will re-enter the atmosphere
Duck! The sky... err... moon is falling!
Not.
Things must fall out of Low Earth Orbit because there's friction from thin atmosphere that slows them down. In higher orbital planes, there's very little to cause a satellite (artificial or natural) to slow down.
They're at orbital velocity. It isn't going to fall, it's just going to sit near the station. And if any of it collides with micro-meteorites or space debris, it could come back and hit the station.
Not to mention that they'd create a minefield for resupply missions.
Considering that I have no idea where they'd get the required amounts of antimatter from, I think the military is having fun blowing smoke up our collective asses. (And those of our enemies.) However, the military *may* be looking into Antimatter catalyzed fissionweapons. Such weapons would need only a few particles of antimatter to fuel a fission warhead that could fit in the palm of your hand.
Unless, of course, you use an ion engine from the LEO onwards.
Except that standard ION engines take months to boost a craft to lunar orbit. That's a very long time to have humans cooped up in a spaceship. You could improve the flight time by using large banks of ION engines, but that adds significant weight. Nuclear ION may be a good compromise, but Prometheus is still being developed.
If you're really bold, you could even use a nuclear salt water rocket.
NSWR is a serious overkill for a LEO to Moon flight. Assuming we had working engines (which we don't) you'd want to use them very carefully or you'd overshoot. Nuclear Thermal (e.g. NERVA, Dumbo, Timberwind, etc.) are well understood and would make excellent choices for LEO to moon taxis. But for a one-off mission, they'd be very heavy and very expensive.
Yeah, I read that book too. The thing is, it is fiction
Never seen it before.
While I'm sure YOU could swap out the shuttle propulsion system in LEO.
I wasn't suggesting anything of the sort. The space shuttle has fuel lines that run from the external tank to the shuttle's main engines. These lines are severed in the last stages of flight, and the tank eventually de-orbits and burns up. Depending on the design of those lines, a new set of tanks could be reattached.
If that proves to be infeasible (a very strong possibility), then external engines could be used instead. The tank/engine clusters that would be launched on the Delta IIs would dock with each other and provide space for the shuttle to dock. An exact fit wouldn't be necessary. The platform could easily fit over the wing surfaces and around the back of the craft. The attachments don't need to be load bearing, they just need to be such that the platform doesn't float away. Simple ties would even do the trick.
This would work, because the thrusters don't need to produce high amounts of thrust. The vehicle will only be changing its orbit, not trying to escape the Earth's gravity. Thus the structures only need to transmit a minimal amount of thrust. e.g. One tenth of a gravity would be more than sufficient thrust as long as it thrusts for long enough.
More efficient != cheaper. Easier to accomplish == cheaper
A Saturn V cost 7.4 billion 1966 dollars to develop, and launched for $431 million 1967 dollars. I can buy a small fleet of Falcon Vs or Delta IIs (think $10 - $50 per launch) for way less, and send all the tanks and materials I need to LEO.
Obviously the Space Shuttle isn't the most cost effective way to accomplish the staging. Each flight is very expensive and hauls fragile humans along for no reason. If I were to look into getting to the moon FAST, I'd probably launch all the tank clusters on commercial rockets, build a lunar lander from existing designs, and use the Shuttle as the moon orbital vehicle. The mission plan would look something like this:
1. Launch all booster tanks on a series of Delta rockets. 2. Launch the space shuttle with the lunar lander in the cargo bay. 3. Mate the shuttle and booster tanks in LEO. 4. Calculate trajectory and fire the shuttle toward the moon. 5. The shuttle achieves lunar orbit and deploys the module from its cargo bay. 6. Module lands, plants a flag, lifts off again. 7. Module mates with the shuttle. 8. The shuttle uses remaining fuel to boost to a retrograde earth orbit. 9. The shuttle jettisons the booster tanks (and the module?) and returns to Earth.
Obviously, specialized vehicles could accomplish a LEO -> Moon flight for far less in flight costs. But one would have to keep the development costs in mind.
A lunar shot is more or less out of question. Have you seen a Saturn rocket? It bigger than most office buildings - even if you had to biggest ship in the world you couldn't carry that to altitude, and it would make shit all difference compared to adding another stage.
Poppycock. There's no need for a Saturn V super-booster to get to the moon. There's only a need for a LEO craft that can carry a few tons of cargo. Stage the necessary fuels and materials in LEO, and you'll be able to use them to boost to the moon from LEO. We could do it with the Space Shuttle if we wanted. Just fly a few fuel tanks or small SRBs up there, and deposit them in LEO. On the last launch, you strap the booster tanks to the shuttle and ignite them. Depending on how much fuel you sent up there, the shuttle would reach the moon in anywhere from a few months to a few days.
You only need a flaming office building if you want to get from the ground to the moon directly. The original US plan was to use a space station as a staging point, but the Jupiter rocket clusters were proving to be so successful that the plans for a station were scraped. Ah, the 1960s. When getting to the moon faster was more important than how much we spent to do it.
Seems you're right. I must have miskeyed that number when I punched them into Google. That definitely makes me feel a bit better, but with the massive gap between the first unofficial and official numbers, I'm still hanging onto the edge of my seat.
BTW, did anyone else notice that NASA TV didn't cover this flight? It's too bad, because the Ansari X-Prize feed was completely useless. Once people jumped onto the webcast, the poor server just didn't have the bandwidth to keep up.
According to those numbers, the first flight was several kilometers lower than the number given by the Mojave radar. i.e. The X-Prize foundation says that SpaceShipOne only went ~102 km, while the unofficial numbers has said ~117 km. This time SpaceShipOne only went to 368,000 (~102km) according to the unofficial numbers. (CNN said that 328,000 is the cutoff point, not the altitude) Given how much lower that number is, I'm sweating bullets until I get the numbers from the X-Prize foundation.
No, there's only one iframe. The field name is passed in the function so that it can be properly identified. Creating iframes all over the place would stress out the browser, possibly resulting in browser crashes.
Slashdot Mirror
The article also mentions if the hydrogen tanks are charged from an external source, it can go as far as a conventional vehicle.
:-)
I understood that perfectly.
The big deal here is it's capable of producing it's own hydrogen/fuel, even if only a little bit at a time.
Nothing new here. The idea has been considered many times, but rejected for its low energy yield. The project is cool, but it's not groundbreaking.
If fuel stations were set up to use larger solar arrays than would fit on a car, or even power from the grid, much more fuel could be produced.
That's a very good idea. That's why I believe I included it at the end of my original post.
If I'm not mistaken, the byproduct of hydrogen combustion is water, so assuming a closed system, it would theoretically have the capability/raw material to run for a good long time.
Assuming a closed system (your car), you'd run out of water sooner than you would have run out of gasoline. Hydrogen is less energy dense than petroleum.
So long as there's a source of electricity (solar, battery, generator on bike pedals), there's the potential to refuel itself.
Agreed. The problem everyone is trying to solve is, "where can we get a constant dozen or so kilowatts of power?"
or unpack a stationary bike and pedal for a while until you have enough hydrogen to get on your way
Perfectly feasible. Your body can sustain about 200 watts of constant output (sometimes a bit more if you're in good shape). That means you should be about to get about 10 minutes of drive time in only (10,000 j * 60 seconds * 10 minutes / 200 j/s = 30,000 seconds = 500 minutes = 8.3 hours). I suggest you walk.
Or how about using an alternator to continuously generate power as the vehicle is moving?
Where do you think the power is coming from to drive the alternator? Probably the engine. The engine is powered by hydrogen. The hydrogen contains X amount of power and no more.
I know it sounds like it would work on the outset, but you just described a perpetual motion machine.
No matter how many ways I try to parse your post, you're not making any sense. Allow me to explain:
The energy used by the car for propulsion is the energy already stored in the water.
No, it's stored in the hydrogen. The water is "pre-burned" hydrogen and oxygen. At a perfect conversion rate, it takes exactly as much energy to convert water to hydrogen and oxygen as you get from making hydrogen and oxygen into water.
In other words, you add energy to the system and it gets stored in a fuel form. The energy doesn't already exist in the system.
The energy from the solar panels is not the limiting factor.
Eh? Let's say we get 200 watts/m^2 of sunlight. The solar panels are only going to be ~20% efficient. That brings us down to 40 watts of energy. The electrolyzer is probably about 50% efficient, bringing our final storage rate to ~20 joules per second. That works out to about 72 kilojoules per hour. Which at a "mere" 2kw of constant use would provide exactly 36 seconds of driving time. (Actually less due to further inefficiencies.)
They'd actually get more power by storing the solar power in batteries, then using an electric drive. The only trick is that batteries tend not to be as energy dense as hydrogen.
Now, it might be true that even at perfect efficiency, you'll never get enough hydrogen from the water using solar power, but that's a different calculation that what you're doing.
What calculation am I doing? Energy is energy, and power is power. You've only got so much of it in a system, so you have to make the most of it.
Although the truck performs as planned, it's more of a demonstration project than a practical vehicle. The four solar panels and hydrogen-generating system create only enough fuel per day to travel a few miles.
:-)
And it's not going to go any farther. On an average day, you're lucky to receive about 200 watts/m2 of sun power. The rest of the energy (about 1.3kw/m2) is lost to diffusion and blockage by the atmosphere.
We've discussed this before on Slashdot, and it has been felt that Sun power could be a great "fuel saver" idea for hydrogen cars. But moving something the size of a modern car is going to require more energy than you can collect from sunlight. (IIRC, ~2 kw to cruise and 10kw to accelerate a small car.)
That being said, I applaud their efforts in the direction of alternative energy sources. Hydrogen is simply not as powerful as petroleum products, but it's pretty close. Concepts like creating fuel with a built-in electrolyzer could be the key to making hydrogen cars seem just as powerful and efficient as petroleum vehicles.
Now if they wanted to prove that hydrogen fill stations could use large Solar Power arrays to power their electrolyzer, then I'm with them all the way.
That "guy" was Garth Knight, the real Knight son. (As opposed to Michael Knight who took the identity to cover his death.) The truck was called Goliath and had no AI.
According to this page they used several different models for both KITT and KARR. I think you might be right about the headlights, though. What I'm thinking about are probably the parking/fog-lights which have a different looking slit between models. Also, the front grill seems to be a bit sleeker in some models than in others.
AKAIK, it's the only high compression video codec to not be encumbered by patents. (Although I've heard whispers from the OGG/Vorbis team.) That right there makes it worth development. Once the codec reaches a stable version, it can be integrated into free player solutions like HelixPlayer and VLC.
See? I did watch more TV! ;-)
BTW, did you ever notice how KITT changed his model throughout the series? In some episodes, he was of a model with popup headlights. In other episodes, he was a model with forward beam lights. Which one was *really* KITT?
They also pulled the same stunt with KARR.
Yep:
KITT = Knight Industries Two Thousand
KARR = Knight Automatic Roving Robot
So I watched a lot of TV as a kid. So sue me. (Not that I'm worth anything.)
Don't forget about the Wing Commander series which was already a movie mixed with a game. Yet they screwed even THAT up when they moved it to the big screen. What would be so horrible about taking the existing actors and doing a story set anywhere they want in the timeline? Improve the sets, effects, etc. and they would have had a pretty good movie. But no, they had to go and "re-imagine" it.
Blech.
It's funny because this movie has been in the works since Doom II came out. At the time, there was a blurb in PC Gamer about how they were going to make a movie out of Doom. Then Quake came along and there was another blurb about plans having switched to a Quake movie. Now (some decade later) they're talking about a Doom movie again. And every last announcement was supposed to be "a sure thing".
The only sure thing about Hollywood is that they'll run you around in circles. Maybe we should give the movie to Bollywood. Then the grunt can get up and sing after he kills the evil cacodemon!
What are you trying to do? Shut down the Mozilla project?!? If you absolutely NEED to see the bug, go to MirrorDot and look it up there.
It would probably bounce off the atmosphere then. Remember that you are not sending the object down, you're skewing its path. Thus the object's trajectory would look a lot like a stone thrown outward toward the water. Gravity pulls the stone down, but that only serves to skew its trajectory. The result is that the stone skims the surface and bounces before it can lose enough velocity.
Remember, LEO orbital velocity is at least 9.7 kilometers per second. If your car was traveling that fast, you'd be burnt to a crisp within seconds.
You might find this article interesting. It seems that after Eisenhower's mispronunciation of "Nuclear" as "Nucular", the military took up the name as a way of distinguishing "Nucular Weapons" (Bad! Evil! Hiss!) from "Nuclear Energy" (Good! Clean! Wonderful!). Their idea is to promote nuclear power through an intentional separation of the two in the language.
Whether it's working or not is for the public to decide, but my guess is that Bush is using the term "Nucular" on purpose. Especially since he's shown that he's perfectly capable of using terms like "Nuclear Medicine".
It doesn't go down like you think. Instead its orbit flattens and it might come back and smack you when you least expect it. (Draw a circle and an elipse around a point. See where they cross? That's the problem.)
Eventually of course, everything in orbit will re-enter the atmosphere
Duck! The sky... err... moon is falling!
Not.
Things must fall out of Low Earth Orbit because there's friction from thin atmosphere that slows them down. In higher orbital planes, there's very little to cause a satellite (artificial or natural) to slow down.
They're at orbital velocity. It isn't going to fall, it's just going to sit near the station. And if any of it collides with micro-meteorites or space debris, it could come back and hit the station.
Not to mention that they'd create a minefield for resupply missions.
Considering that I have no idea where they'd get the required amounts of antimatter from, I think the military is having fun blowing smoke up our collective asses. (And those of our enemies.) However, the military *may* be looking into Antimatter catalyzed fissionweapons. Such weapons would need only a few particles of antimatter to fuel a fission warhead that could fit in the palm of your hand.
Unless, of course, you use an ion engine from the LEO onwards.
Except that standard ION engines take months to boost a craft to lunar orbit. That's a very long time to have humans cooped up in a spaceship. You could improve the flight time by using large banks of ION engines, but that adds significant weight. Nuclear ION may be a good compromise, but Prometheus is still being developed.
If you're really bold, you could even use a nuclear salt water rocket.
NSWR is a serious overkill for a LEO to Moon flight. Assuming we had working engines (which we don't) you'd want to use them very carefully or you'd overshoot. Nuclear Thermal (e.g. NERVA, Dumbo, Timberwind, etc.) are well understood and would make excellent choices for LEO to moon taxis. But for a one-off mission, they'd be very heavy and very expensive.
Yeah, I read that book too. The thing is, it is fiction
Never seen it before.
While I'm sure YOU could swap out the shuttle propulsion system in LEO.
I wasn't suggesting anything of the sort. The space shuttle has fuel lines that run from the external tank to the shuttle's main engines. These lines are severed in the last stages of flight, and the tank eventually de-orbits and burns up. Depending on the design of those lines, a new set of tanks could be reattached.
If that proves to be infeasible (a very strong possibility), then external engines could be used instead. The tank/engine clusters that would be launched on the Delta IIs would dock with each other and provide space for the shuttle to dock. An exact fit wouldn't be necessary. The platform could easily fit over the wing surfaces and around the back of the craft. The attachments don't need to be load bearing, they just need to be such that the platform doesn't float away. Simple ties would even do the trick.
This would work, because the thrusters don't need to produce high amounts of thrust. The vehicle will only be changing its orbit, not trying to escape the Earth's gravity. Thus the structures only need to transmit a minimal amount of thrust. e.g. One tenth of a gravity would be more than sufficient thrust as long as it thrusts for long enough.
More efficient != cheaper.
Easier to accomplish == cheaper
A Saturn V cost 7.4 billion 1966 dollars to develop, and launched for $431 million 1967 dollars. I can buy a small fleet of Falcon Vs or Delta IIs (think $10 - $50 per launch) for way less, and send all the tanks and materials I need to LEO.
Obviously the Space Shuttle isn't the most cost effective way to accomplish the staging. Each flight is very expensive and hauls fragile humans along for no reason. If I were to look into getting to the moon FAST, I'd probably launch all the tank clusters on commercial rockets, build a lunar lander from existing designs, and use the Shuttle as the moon orbital vehicle. The mission plan would look something like this:
1. Launch all booster tanks on a series of Delta rockets.
2. Launch the space shuttle with the lunar lander in the cargo bay.
3. Mate the shuttle and booster tanks in LEO.
4. Calculate trajectory and fire the shuttle toward the moon.
5. The shuttle achieves lunar orbit and deploys the module from its cargo bay.
6. Module lands, plants a flag, lifts off again.
7. Module mates with the shuttle.
8. The shuttle uses remaining fuel to boost to a retrograde earth orbit.
9. The shuttle jettisons the booster tanks (and the module?) and returns to Earth.
Obviously, specialized vehicles could accomplish a LEO -> Moon flight for far less in flight costs. But one would have to keep the development costs in mind.
Pan who?
A lunar shot is more or less out of question. Have you seen a Saturn rocket? It bigger than most office buildings - even if you had to biggest ship in the world you couldn't carry that to altitude, and it would make shit all difference compared to adding another stage.
Poppycock. There's no need for a Saturn V super-booster to get to the moon. There's only a need for a LEO craft that can carry a few tons of cargo. Stage the necessary fuels and materials in LEO, and you'll be able to use them to boost to the moon from LEO. We could do it with the Space Shuttle if we wanted. Just fly a few fuel tanks or small SRBs up there, and deposit them in LEO. On the last launch, you strap the booster tanks to the shuttle and ignite them. Depending on how much fuel you sent up there, the shuttle would reach the moon in anywhere from a few months to a few days.
You only need a flaming office building if you want to get from the ground to the moon directly. The original US plan was to use a space station as a staging point, but the Jupiter rocket clusters were proving to be so successful that the plans for a station were scraped. Ah, the 1960s. When getting to the moon faster was more important than how much we spent to do it.
Seems you're right. I must have miskeyed that number when I punched them into Google. That definitely makes me feel a bit better, but with the massive gap between the first unofficial and official numbers, I'm still hanging onto the edge of my seat.
BTW, did anyone else notice that NASA TV didn't cover this flight? It's too bad, because the Ansari X-Prize feed was completely useless. Once people jumped onto the webcast, the poor server just didn't have the bandwidth to keep up.
Official X-Prize peak height from first flight
According to those numbers, the first flight was several kilometers lower than the number given by the Mojave radar. i.e. The X-Prize foundation says that SpaceShipOne only went ~102 km, while the unofficial numbers has said ~117 km. This time SpaceShipOne only went to 368,000 (~102km) according to the unofficial numbers. (CNN said that 328,000 is the cutoff point, not the altitude) Given how much lower that number is, I'm sweating bullets until I get the numbers from the X-Prize foundation.
No, there's only one iframe. The field name is passed in the function so that it can be properly identified. Creating iframes all over the place would stress out the browser, possibly resulting in browser crashes.