Actually, analysis of Bussard Ramjet showed that it is a good handbrake!
Inspite of early promise it turned out that the thrust/drag of the ramjet against solar wind and interstellar gas turned out to be below unity. That's bad- you don't go anywhere.
This lead to a concept called M2P2, which is an 'inflatable' plasma. You turn it on and it expands out to a few tens of kilometers, the solar wind pushes on it, and a few months later you are leaving the solar system at high speed, dragged along by the plasma. Basically they ditched the drive system, and just used the collection field.
It worked in a small scale lab test, but nobody knows whether it will really expand out to a few tens of kilometers, and there were a few potential problems, such as tending to vapourise the vehicle due to the very high temperatures of the plasma, still it shows some promise, it's similar to the way the Earths magnetosphere operates.
Next up we have the VASIMR... it can produce hard thrust like a chemical rocket.
'Fraid not. To do that requires an enormous, lightweight, electrical power source. No current powerplant, solar, nuclear, chemical or other can provide enough power to generate high thrust when used with VASIMR.
VASIMR is a wannabe fusion power drive. Trouble is, fusion doesn't work well enough right now to use it for this; and they are stuck with trying to powering it the old fashioned ways. It works, but not noticeably any better than ion drive- if you were to get VASIMR to work with a new power supply, you can pretty much just gang up any of the existing ion drive thrusters and get about the same thrust.
VASIMR has theoretical advantages of being able to vary the exhaust velocity to increase the thrust, but even on the lowest settings I've seen them talk about, ion drives usually give better thrust.
The question is however, would the private sector, on its own, do as well? Again, the kernel of my argument is that Rutan did not do the basic research on composites, only the applied R&D.
Well, technically wood is a mixture of polymers in a particular matrix shape and so counts as a composite material, so even the very earliest aeroplanes were composite. Companies do do quite a bit of research themselves- the idea that only government does this is falacious. I mean, for example, the internet came out of arpanet (government), but there were lots of companies working on much the same thing as well, for example Xerox Parc developed a system with networking, a mouse, windowing and object oriented programming.
(and going back to NACA, keep in mind that it was govt money that seeded the development of the airplane and airline industry).
Not really- the Wright brothers didn't use government funding to develop the airplane, and that was the true seed. The airline industry you may be able to argue was developed with government money; but we'll never know what would have happened if they hadn't done this- we may very well have had airliners anyway due to organic growth.
The lighter weight of a more expensive alloy and not throwing away the fuel tanks might have made the cost/flight cheap enough to be competative.
It wasn't really expense that precluded NASA from using titanium- it was the fact that the Russians controlled the world supply, and the Military wanted every little bit they could get their hands on.
Throwing away the tanks actually seemed to be a good idea at the time...
Scaled composites was started because he had proven expertise in composite aerospace vehicles, and Scaled composite was the company he started to leverage that to generate income.
Gravitation? What do you mean? Lack of on the surface? Or lack of gravity in space. Either way, we've solved this problem.
Actually, the gravity of Mars is a problem. The surface gravity is 1/3 of Earth normal. Absolutely no experimental evidence exists to show that that is enough to prevent the osteoporosis we see in zero-g. All the existing long-term experience is at 1g or 0g and nothing inbetween.
In addition, Mars's escape velocity is about 6km/s. That's awkwardly high, although it can be dealt with.
No, the rotation (rpm) of the earth is the same everywhere, but the diameter varies- the equator is further from the axis than nearer the pole. So it rotates in the same time, but has further to go- so it is going faster- about 300 m/s faster.
Now, the escape velocity is the same everywhere, but you get a headstart.
It is also true that launching nearer the equator helps with orbits- it's only possible to launch to an orbit that passes over the launch site (without doing a 'dogleg' which wastes lots of fuel.) All orbits cross the equator, so it's the best place to launch from that point of view. However, the equatorial orbits don't pass over, say, Kazakhstan or New York, so you can't as efficiently launch from there to Geosynchronous orbits or other near-equatorial orbits.
Right... so you are saying that reentering the earths atmosphere at about mach 26 with enough kinetic energy to vapourise every single part of the spacecraft, leaving a plasma trail behind and landing safely on the ground, is as dangerous as watching the inflight entertainment to LA?
Well, I've been bored, but never bored to death.
These astronauts in a Soyuz face a 1% death rate (2% for Shuttle astronauts), and you are laughing at them...
Nope. Rockets, and jet engines are classed as internal combustion engines. External combustion engines typically go through the steam or Stirling cycle, where the working fluid is kept distinct from the combustion.
If you read the article more carefully, you see that the designer went to great lengths to make the design completely symmetrical, (for example figuring out how many bricks thickness are needed to make cubical parts and such like) so if it can rotate one side, it can rotate all of them; just like the original Rubik's cube.
Actually a relatively young bunch of guys in America died of CJD. Turned out they'd all eaten scrambled egg mixed with squirrel brains- a local delicacy.
Presumably, the Squirrel had had CJD, and they'd caught it.
So, those tree rats can kill if sufficiently provoked!:-)
Certainly the backlighting current would be slashed, because the area of display is so much smaller; so for the same intensity you need a tiny, tiny fraction. The drive circuitry (including 3D rendering card:-) ), would be pretty similar power though.
Still, you might be able to double battery life for the same battery size.
Then there are are low power processors like Transmeta's.
The other heavy current device is the hard-drive. It's getting to the point where replacing that with camera-style flash memory is getting to be closer to cost-effective.
I guess the ultimate small/longlife laptop replacement system would have datagloves instead of keyboard.
Maybe with WiFi and 3G connectivity the system might actually be geeky enough to actually be chic , or not:-)
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Inspite of early promise it turned out that the thrust/drag of the ramjet against solar wind and interstellar gas turned out to be below unity. That's bad- you don't go anywhere.
This lead to a concept called M2P2, which is an 'inflatable' plasma. You turn it on and it expands out to a few tens of kilometers, the solar wind pushes on it, and a few months later you are leaving the solar system at high speed, dragged along by the plasma. Basically they ditched the drive system, and just used the collection field.
It worked in a small scale lab test, but nobody knows whether it will really expand out to a few tens of kilometers, and there were a few potential problems, such as tending to vapourise the vehicle due to the very high temperatures of the plasma, still it shows some promise, it's similar to the way the Earths magnetosphere operates.
'Fraid not. To do that requires an enormous, lightweight, electrical power source. No current powerplant, solar, nuclear, chemical or other can provide enough power to generate high thrust when used with VASIMR.
VASIMR is a wannabe fusion power drive. Trouble is, fusion doesn't work well enough right now to use it for this; and they are stuck with trying to powering it the old fashioned ways. It works, but not noticeably any better than ion drive- if you were to get VASIMR to work with a new power supply, you can pretty much just gang up any of the existing ion drive thrusters and get about the same thrust.
VASIMR has theoretical advantages of being able to vary the exhaust velocity to increase the thrust, but even on the lowest settings I've seen them talk about, ion drives usually give better thrust.
Since death is defined as brain death, all of them; by definition :-)
I imagine Burt's position would be along the lines of: "If NASA would fund Burt Rutan then nothing would get done."
The reason is that NASA runs on an incredibly high load of paperwork; you spend most of the money they give you just filling in their paperwork.
You may like to look it up, and find out where your logic has failed here.
Well, technically wood is a mixture of polymers in a particular matrix shape and so counts as a composite material, so even the very earliest aeroplanes were composite. Companies do do quite a bit of research themselves- the idea that only government does this is falacious. I mean, for example, the internet came out of arpanet (government), but there were lots of companies working on much the same thing as well, for example Xerox Parc developed a system with networking, a mouse, windowing and object oriented programming.
(and going back to NACA, keep in mind that it was govt money that seeded the development of the airplane and airline industry).
Not really- the Wright brothers didn't use government funding to develop the airplane, and that was the true seed. The airline industry you may be able to argue was developed with government money; but we'll never know what would have happened if they hadn't done this- we may very well have had airliners anyway due to organic growth.
It wasn't really expense that precluded NASA from using titanium- it was the fact that the Russians controlled the world supply, and the Military wanted every little bit they could get their hands on.
Throwing away the tanks actually seemed to be a good idea at the time...
I'd say, if I were in Rutan's shoes- head for Brazil, the weathers great!
I'd say he'd probably have gone; for example, all the way around the world without refuelling.
Scaled composites was started because he had proven expertise in composite aerospace vehicles, and Scaled composite was the company he started to leverage that to generate income.
Worth getting married just for extra porn. Why didn't anyone tell me?
Actually, the gravity of Mars is a problem. The surface gravity is 1/3 of Earth normal. Absolutely no experimental evidence exists to show that that is enough to prevent the osteoporosis we see in zero-g. All the existing long-term experience is at 1g or 0g and nothing inbetween.
In addition, Mars's escape velocity is about 6km/s. That's awkwardly high, although it can be dealt with.
Backwards- right? v=rw means your linear velocity is the product of the angular velocity and the radius.
But I certainly knew what you meant.
the Earth rotates 360 degrees every day
Actually, no. It rotates more than that each day.
Since you're interested in achieving a certain fixed v (I think it's around 42 km/s on Earth)
Much slower, about 7.8 km/s
Now, the escape velocity is the same everywhere, but you get a headstart.
It is also true that launching nearer the equator helps with orbits- it's only possible to launch to an orbit that passes over the launch site (without doing a 'dogleg' which wastes lots of fuel.) All orbits cross the equator, so it's the best place to launch from that point of view. However, the equatorial orbits don't pass over, say, Kazakhstan or New York, so you can't as efficiently launch from there to Geosynchronous orbits or other near-equatorial orbits.
Yes, it has been called a joke.
Well, I've been bored, but never bored to death.
These astronauts in a Soyuz face a 1% death rate (2% for Shuttle astronauts), and you are laughing at them...
Nope. Rockets, and jet engines are classed as internal combustion engines. External combustion engines typically go through the steam or Stirling cycle, where the working fluid is kept distinct from the combustion.
If you read the article more carefully, you see that the designer went to great lengths to make the design completely symmetrical, (for example figuring out how many bricks thickness are needed to make cubical parts and such like) so if it can rotate one side, it can rotate all of them; just like the original Rubik's cube.
No, rocket engines are more powerful, they can provide thrust/weight ratios as high as a 100:1 or more.
We do all wait with baited breath for your explanation of why men have different ratios of finger lengths than women in the first place.
Presumably, the Squirrel had had CJD, and they'd caught it.
So, those tree rats can kill if sufficiently provoked! :-)
Yeah? And this is relevant to prenatal exposure to testosterone how exactly? RFTA.
a) logical (as you put it, 'obvious')
b) surprising
However, just about everyone that I have ever explained this to has violently disagreed. That's how I know it has to be true.
For example, the worlds oldest joke (picture cavewoman running towards her mate):
Cavewoman: "Ug, ug, my mother is trapped in a cave with a sabertooth tiger!"
Mate: "What do I care what happens to a sabertooth tiger?"
No. It clearly isn't, yet, since Duke Nukem Forever hasn't gone gold.
If that happens start praying.
There's no necessary reason that it has to wear at all: hydrostatic or hydrodynamic bearings are used on hard-drives and don't wear.
Still, you might be able to double battery life for the same battery size.
Then there are are low power processors like Transmeta's.
The other heavy current device is the hard-drive. It's getting to the point where replacing that with camera-style flash memory is getting to be closer to cost-effective.
I guess the ultimate small/longlife laptop replacement system would have datagloves instead of keyboard.
Maybe with WiFi and 3G connectivity the system might actually be geeky enough to actually be chic , or not :-)