Manned Spaceflights
USA Today had a front page article about NASA's mission and the balance between science and manned spaceflight and President Bush's "vision" for humans to return to the moon and onward to Mars in the coming decades.
It opened the thought that hadn't occured to me before:
What is the Purpose of human spaceflight? What can humans do in space the robots can't do?
Well, it might not be that simple. Apparently the Hubble space telescope can be much more cheaply serviced by humans than robots.
Certainly you can argue there's "science" in learning about the effects of space (weightlessness) on humans, and the challenges of the extreme environment of space encourage technical advances in efficient use of resources and recycling.
The article had some quotes that suggested that space tourism is the way to go for the purpose of humans in space. Obviously as-is, traveling into space is too expensive to all but perhaps a few hundred of the superwealthy of the world.
The Spaceship One experimental civilian spacecraft was perhaps a good start last year, even if it was far short of reaching orbital velocity. Perhaps "airplane" models of launching can help cut the energy costs of getting into space. Myself, I don't know. Obviously air helps airplanes keep in flight with less energy than a mere trajectile.
My guess is that "small scale" aircraft/rockets are NOT more efficent energywise. It seems clear that if you're talking payload efficiency, you want to minimize "dead weight" and maximize cargo plus fuel. Larger rockets have less dead weight than smaller ones because there is a minimum weight needed for the structural weight of the rocket.
Perhaps "new materials" are part of the answer to make smaller rocket/aircraft effective.
If you're talking energy itself, I expect that overall we can only do what we do because of cheap fossil fuels, and in the future we won't have the energy available, or at least it won't be a priority.
I believe whether manned or unmanned missions, reducing the energy requirements for getting mass into orbit is a vital area of research. I accept than manned missions, which are more demanding mass-wise, PLUS possible "market" for tourism, might be what it takes to develop more efficient travel into space, while small science missions might just keep on as-is because NASA's costs outside fuel are still dominant.
I find it hard to believe spacetravel will ever be cost-effective for "space tourism". I mean in the short term you might find a few superwealthy candidates, but just think of the airline industry now - how they're being killed by fuel costs. A few hundred dollars to travel across the U.S. is very cheap now. I wonder how much prices could increase or how that would affect air tourist travel volume. I imagine a graph might be extrapolated - double the cost, and cut travel by 25% perhaps. Quadruple the cost and cut by 50%. And as travel volume is cut, fixed costs will rise quickly to increase costs further.
Perhaps for spacetravel tourism we'll have costs like:
That's fully made up, but who knows? Even if my demand vs cost table is realistic, the question is what is a projected cost? (Of course it also must define what level of space people are getting - I think suborbital is not acceptable, but I guess that would be a different graph. I'd expect people would like to say spend 10 days in space, and of course then you have to have a place to put them - like the space station. If we get 50,000 people/year, 1000/week, how big would a space station have to be to support them all?
Perhaps it could be expanded to support so many people, but looking at the gross revenue side, NASA spends $6 billion/year for the Shuttle and space station, so this WORLD market potential appears to be under 10% of NASA's budget.
It seems unlikely to me that you could get the customers to support R&D to a point that might make it feasible. It would HAVE to be subsidized, but by who? I suppose NASA could do R&D and civilian businesses could capitalize on advances.
Overall my judgement is that science missions for the indefinite future ought to be the first priority for NASA.
If we want to do research on human space travel we have plenty of research we can continue more cheaply on earth.
I might be wrong, and I admit I am awed and inspired all around by space travel. We've learned much in a short period of time. We truly live in interesting times!
Someday our descendants, hundreds of years from now, might look up at the moon and tell their children "fairy tales" of men who landed on the moon, and no one will really know if it happened.
It opened the thought that hadn't occured to me before:
What is the Purpose of human spaceflight? What can humans do in space the robots can't do?
Well, it might not be that simple. Apparently the Hubble space telescope can be much more cheaply serviced by humans than robots.
Certainly you can argue there's "science" in learning about the effects of space (weightlessness) on humans, and the challenges of the extreme environment of space encourage technical advances in efficient use of resources and recycling.
The article had some quotes that suggested that space tourism is the way to go for the purpose of humans in space. Obviously as-is, traveling into space is too expensive to all but perhaps a few hundred of the superwealthy of the world.
The Spaceship One experimental civilian spacecraft was perhaps a good start last year, even if it was far short of reaching orbital velocity. Perhaps "airplane" models of launching can help cut the energy costs of getting into space. Myself, I don't know. Obviously air helps airplanes keep in flight with less energy than a mere trajectile.
My guess is that "small scale" aircraft/rockets are NOT more efficent energywise. It seems clear that if you're talking payload efficiency, you want to minimize "dead weight" and maximize cargo plus fuel. Larger rockets have less dead weight than smaller ones because there is a minimum weight needed for the structural weight of the rocket.
Perhaps "new materials" are part of the answer to make smaller rocket/aircraft effective.
If you're talking energy itself, I expect that overall we can only do what we do because of cheap fossil fuels, and in the future we won't have the energy available, or at least it won't be a priority.
I believe whether manned or unmanned missions, reducing the energy requirements for getting mass into orbit is a vital area of research. I accept than manned missions, which are more demanding mass-wise, PLUS possible "market" for tourism, might be what it takes to develop more efficient travel into space, while small science missions might just keep on as-is because NASA's costs outside fuel are still dominant.
I find it hard to believe spacetravel will ever be cost-effective for "space tourism". I mean in the short term you might find a few superwealthy candidates, but just think of the airline industry now - how they're being killed by fuel costs. A few hundred dollars to travel across the U.S. is very cheap now. I wonder how much prices could increase or how that would affect air tourist travel volume. I imagine a graph might be extrapolated - double the cost, and cut travel by 25% perhaps. Quadruple the cost and cut by 50%. And as travel volume is cut, fixed costs will rise quickly to increase costs further.
Perhaps for spacetravel tourism we'll have costs like:
| Cost/person | People/year | Gross revenue |
| $100 million | 0.1 | $10 million |
| $10 million | 3 | $30 million |
| $1 million | 50 | $50 million |
| $100,000 | 1000 | $100 million |
| $10,000 | 50,000 | $50 million |
That's fully made up, but who knows? Even if my demand vs cost table is realistic, the question is what is a projected cost? (Of course it also must define what level of space people are getting - I think suborbital is not acceptable, but I guess that would be a different graph. I'd expect people would like to say spend 10 days in space, and of course then you have to have a place to put them - like the space station. If we get 50,000 people/year, 1000/week, how big would a space station have to be to support them all?
Perhaps it could be expanded to support so many people, but looking at the gross revenue side, NASA spends $6 billion/year for the Shuttle and space station, so this WORLD market potential appears to be under 10% of NASA's budget.
It seems unlikely to me that you could get the customers to support R&D to a point that might make it feasible. It would HAVE to be subsidized, but by who? I suppose NASA could do R&D and civilian businesses could capitalize on advances.
Overall my judgement is that science missions for the indefinite future ought to be the first priority for NASA.
If we want to do research on human space travel we have plenty of research we can continue more cheaply on earth.
I might be wrong, and I admit I am awed and inspired all around by space travel. We've learned much in a short period of time. We truly live in interesting times!
Someday our descendants, hundreds of years from now, might look up at the moon and tell their children "fairy tales" of men who landed on the moon, and no one will really know if it happened.
posted by Ares Olympus at 7:44 PM
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