NASA's Vision
So what do you all think NASA should be doing? Don't worry, I'm not in any kind of position to do anything about it... I'd just like your opinions.
In the 50's, the folks who would become NASA's leaders put out a vision of pinwheel space stations, shuttles between these and the earth and the moon, and nuclear rockets to the planets. They order they had in mind was 1) spaceplane 2) space station 3) lunar shuttle 4) lunar base 5) Mars shuttle 6) Mars base. As we know, Kennedy inverted this and put the moon first, but we've never gone back. Call this strategy "exploration."
In the mean time, we've found that we can do all sorts of science in space that is exciting to both the public and the science community. Everyone knows about Voyager, Viking, Hubble, and the Mars rovers, but there are many many more, such as Chandra (which made the X-ray image of the Galactic Core Tom posted), COBE and MAP, which studied the "echo" of the Big Bang. Call this strategy "science."
Currently, there is a new exploration vision for NASA that takes us back to the Moon, with a replacement for the Shuttle that we'd be able to send beyond Earth orbit. Eventually, the idea is that this model will get us to Mars, maybe even by the time our generation starts to retire. But to make this happen, we have to choose between putting more tax money into NASA's budget, or cut back on science (or at least the kinds of science that don't contribute more or less directly to exploration).
Of course, it's really much more complicated than I'm making it out to be, but to keep it simple, let's assume NASA's budget is fixed, and give a percentage for science vs. exploration.
(Don't worry about offending me; having worked on both sides of this issue, I really can see it both ways!)
In the 50's, the folks who would become NASA's leaders put out a vision of pinwheel space stations, shuttles between these and the earth and the moon, and nuclear rockets to the planets. They order they had in mind was 1) spaceplane 2) space station 3) lunar shuttle 4) lunar base 5) Mars shuttle 6) Mars base. As we know, Kennedy inverted this and put the moon first, but we've never gone back. Call this strategy "exploration."
In the mean time, we've found that we can do all sorts of science in space that is exciting to both the public and the science community. Everyone knows about Voyager, Viking, Hubble, and the Mars rovers, but there are many many more, such as Chandra (which made the X-ray image of the Galactic Core Tom posted), COBE and MAP, which studied the "echo" of the Big Bang. Call this strategy "science."
Currently, there is a new exploration vision for NASA that takes us back to the Moon, with a replacement for the Shuttle that we'd be able to send beyond Earth orbit. Eventually, the idea is that this model will get us to Mars, maybe even by the time our generation starts to retire. But to make this happen, we have to choose between putting more tax money into NASA's budget, or cut back on science (or at least the kinds of science that don't contribute more or less directly to exploration).
Of course, it's really much more complicated than I'm making it out to be, but to keep it simple, let's assume NASA's budget is fixed, and give a percentage for science vs. exploration.
(Don't worry about offending me; having worked on both sides of this issue, I really can see it both ways!)
posted by R @ 7:32 PM
6 Comments:
At 9:00 AM,
Unknown said…
OK. I'll bite.
Part I.
I don't think we'll be able to do anything substantially different from what we have already done (putting a handful of persons at a time somewhere near the earth or the moon, putting smallish robotic spacecraft into orbit or on interplanetary trajectories a few times a year) until we start developing nuclear launch vehicles.
Yes, with a huge effort we can slowly assemble a space station with chemical rockets, but let's face it: the cost of delivering serious payloads from the earth surface to orbit is just too big. Chemistry is just the wrong tool for access to space.
If NASA were serious, it would find a way to sell the development of a safe nuclear launch vehicle. Until someone does this, everything else is really just talk. We've seen what a chemical launch infrastructure can do. That's what we have now.
We need something orders of magnitude better. Continued investing in chemical access to space is like continued investing in the internal-combustion engine for automotive transport. There's only so much efficiency we can squeeze out of the system. It turns out not to be such an immediate big deal for cars, though, because they are efficient enough for present purposes.
The conquest of space, however, is a different story. We need something right now that will change the whole economic picture related to spaceflight.
Part II.
After the development of an economically reasonable launch system, the next goal should be the establishment of a permanent, independently functioning human colony on the moon. The goal should be primarily to make it so that a human presence can continue to exist even if everyone on earth were killed and the surface of the earth rendered uninhabitable without technological life support.
Part III.
After independent life-support infrastructure is established on the moon, it should be exported to other parts of the solar system.
Part IV.
After the solar system is colonized, and a solar-system-wide economy develops, the economic capital to do some really interesting things will become available.
We have already figured out how to harness the resources of an entire planet.
My plan would ensure the survival of humanity and keep us busy for a few hundred years while we think about how to harness the resources of an entire solar system.
At 9:06 AM,
Unknown said…
Sorry. I did not abide by the parameters that you defined for the discussion.
I think that, at least in the short run, we need to invest in launch infrastructure more than in science or in exploration.
At 11:35 PM,
cvo said…
My answer is going to be derived out of ignorance because I do not know enough about the "science" end of NASA's projects. However, I am going to answer based on what I think all of us need the most.
As a species, we are consuming resources (fuel, food, water) at a faster pace than the world can provide. We will run out of oil in our lifetimes, and I fear water will be an even greater issue a few generations from now.
Having said that, I think we have to skew NASA's budget more towards "exploration" (maybe 80%-20%?) in the hopes that we can find more exploitable resources on other planets and in other galaxies. I'm all for searching for extraterrestrial life, but I'm more concerned with providing for the human race before we become extinct.
I understand that the "science" components of NASA's projects can help us live better and longer lives as well, but no amount of science will provide us with enough to satiate our appetite for devouring natural resources to maximum depletion.
At 7:51 AM,
Unknown said…
Curtis, your comment is similar to mine in spirit. You seem concerned for the well being of the human race. I too am concerned, though I think that resource depletion is not the only---nor even necessarily the most important---concern.
Unfortunately, we can't use the resources of our solar system to address our concerns until access to space is affordable and safe. So I think that most of our investment now should focus on new launch technology and launch infrastructure. A nuclear system offers about a thousand times more energy per unit mass than a chemical system. Energy per mass is the ultimate design issue in space launch. Everything hinges on it.
Humanity faces many different threats (some now, some potentially in the future) besides resource depletion: lethal and contagious infectious disease, earth impact by large meteor or comet, large-scale war with thermonuclear fusion bombs, run-away greenhouse effect (as on Venus), eruption of supervolcanoes, conquest by alien civilization, etc.
The best way to ensure the survival of humanity is to work toward the establishment of an independently surviving colony off of Earth. The logical place to build the first one is the Moon because it is so close. This should be our highest priority (after building the launch infrastructure to enable the project). We are very fortunate to have a close neighbor in the Moon; we should take every advantage of it.
And we should start now.
Maybe Russell will be able to disabuse me of my ideas about the importance of serious launch capability. Perhaps there is some essential and obvious piece that I don't recognize, but my opinion right now is that we don't have nuclear launch capability because of political reasons, not because of technical reasons. To be sure, there may yet be unsurmountable technical problems, but I doubt it, and we won't know until we start really working the issue.
My litmus test for the seriousness of politicians and officials is the development of a nuclear launch vehicle. Until the powers that be start talking about it, my opinion is that they are not serious about making use of space travel except for robotic observatories and otherwise maintaining the symbolism of having a few humans in space.
The scientists who whine about the fact that human spaceflight is way too expensive for scientific return are exactly correct. The current space economy, based on chemical energy, doesn't support robust, manned exploration.
At 2:31 PM,
R said…
I'm staying out of this debate; I hope to hear from others. As an aside though, I read an interesting book recently called "Project Orion: The True Story of the Atomic Spaceship" by George Dyson (Freeman Dyson's son). It's about the top secret project in the 50s and early 60s to build a nuclear rocket that would be propelled by exploding nuclear weapons behind it. I know it sounds pretty wild, but they actually believed they could do it, until they started to realize the dangers of blowing these things up in the atmosphere. But something like would solve the dilemma posed by Tom, as there is so much energy available, you could easily launch the Titanic to any planet you wanted. My own view on how to solve the launch problem is that, 100 years from now, we will access space via space elevators that ride up and down tethers of carbon nano-tubes. That's pretty far-fetched too, but we are closer to this than most people realize. Hopefully, nanotech won't turn out to be a big environmental hazard.
At 3:28 PM,
Unknown said…
I'd like to hear from others, too, but it seems that the only ones recently posting with any regularity are, in rough order of decreasing frequency: I, Curtis, Russell, and, occasionally, Lark. I have seen a couple of posts from Michelle recently, and one at long last from Michele, but if nothing changes, then we'll just have two or three opinions represented at most on any given thread.
Russell makes a good point. I amend my earlier litmus test for the serious politician or administrator. If he makes either a nuclear launch system or a space elevator a high priority, then I'll think that he's not just talking about business as usual. Even if the space elevator is the long-term solution, though, a nuclear launch vehicle would likely be the best way forward until it happens. And I don't think that we should wait around for a reliable space elevator.
That reminds me. I also developed a seriousness litmus test for space-elevator advocates a few months ago. After reading all of the space-elevator Web pages that I could find, I decided that none of these guys is serious. Everyone was talking about how to build the ground station and lower the thing from orbit, etc. If someone were really serious, though, his first project would be to anchor a derigible in the stratosphere to a point on the ground. Then all the basic stuff (climbers, etc.) could be tested for a reasonable program cost. When someone starts talking about that, then I'll take the space elevator stuff seriously.
Still, on my long drive to and from work, I have developed a toy design in which a nuclear reactor, situated on the second stage of the launch vehicle, pushes a working fluid (like steam) in a closed loop through turbofans on the first stage. In a vertical take-off scenario, the turbofan first stage takes the payload up, say, to 50,000 feet or so. When it breaks away, the reactor heats the working fluid up more and shoots it straight out the back as rocket exhaust to LEO or further. For earth orbit or otherwise near the sun, solar power and ion engines would seem the best, or else solar sails. For deep space, the nuclear reactor should power ion engines.
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