NASA Vision of Space Exploration

I think you're underestimating the importance of the psychological work still to be done. At this point, no one's figured out a way to get a crew through a mission like that without cooperation breaking down with catastrophic results. That's not even considering the high probability of someone having a total psychotic break and killing everyone.

Psychological issues are the biggest obstacle right now, followed by the cosmic ray shielding, then followed by launch costs.

Currently hung up on the carbon nanotube issue.

 

Though carbon nanotubes exist they are in very short supply. Also they are not indestructable and atmopheric drag and micro meteroites could do long term damage. There are right now contests being conducted for cash prizes for demontrating a climber. Last I checked no one has been able to claim the prize.
A space elevator as envisioned would allow a craft to achieve escape velocity in short order. Once you have climbed the elevator you have expended only the energy needed to climb the elevator which can be supplied by electricty...fission, solar, whatever. The elevator would extend all the way to GEO. At LEO you are already going 17,500 mph. So to get beyond escape velocity you only need enough rocket fuel to increase your velocity by 8,000 mph instead of the full 25,000 mph worth of fuel you'd need if you had launched form the surface of the Earth, basically. MasterAero could probably describe this better.

 

Basic physics formula:

Fg = G*M1*M2/(R^2)

The force of gravity (Fg) is equal to the Gravitational constant (G) times the two masses (M1, the Earth, and M2, the elevator/ship) divided by the square of the distance between their centers of mass.

For someone on the surface of the Earth, R = about 6400km. For someone in geosynchronous orbit (at the top of a space elevator), R would be about 42000km, or about 6-7 times as far.

That means that for the same masses, an object in geosynchronous orbit experiences a force from gravity approximately 1/36 to 1/49 the strength of the force of gravity on the surface of the Earth.

Kimball Kinnison

 

VadersLaMent is right I think about cost being the only obstacle. It's really all about getting enough tons of stuff off the ground using 1940s technology.

But it's a huge obstacle. It would be cost-prohibitive in the same sort of sense that giving every man, woman and child on the planet a BMW would be cost-prohibitive.

 

Nope, there's also some issues about what that much time in space would do to the human body. For example... I think one of the issues is the body losing calcium in zero g, if someone can confirm that one.

 

VadersLaMent is right I think about cost being the only obstacle. It's really all about getting enough tons of stuff off the ground using 1940s technology.

Ah, not so much that. Just because we still use a tube that shoots stuff out the back doesn't make it an antique. The problem is an industrial complex that has had no competition to decrease their costs. Lockheed has stepped up to the plate with Bigelow and the rocket they will use will most certainly not cost someone $20 million for a ride to orbit.

Nope, there's also some issues about what that much time in space would do to the human body. For example... I think one of the issues is the body losing calcium in zero g, if someone can confirm that one.

Oh your right on. But the Russians have already demontrated with Mir that with excercise and intake you can counter this. We have all the technology and know-how to get to Mars. Cost is the only prohibitor.

 

I would say that cost and motivation are the only two prohibitors. If people are motivated enough, they will be willing to pay the high costs. Alternately, if we can lower the costs to the point where people are already motivated enough, they will put up the money.

Kimball Kinnison

 

If they, or we, cannot afford those costs then we can be as motivated as possible but still not be able to do anything about it. If I had $100 million dollars right now I'd call Bigelow and put the money on a module, he will sell them for that price, perhaps cheaper. I will then have my very own spacecraft with which I could go mine out NEA's. I have all the motivation I need for it, but I most certainly lack the funds.

 

My point about technology is that there hasn't been a replacement for the chemical rocket. We have 60 plus years of refinement of the same basic technology, but that sets the basic range of costs for launching stuff into orbit and beyond.

Probably the easiest way to reduce costs for a Mars assault would be to do it as a suicide mission. Ask for volunteers for a one way trip. I bet you'd get people to do it.

 

Individuals may be motivated, but I was referring more to society in general.

The moon landings were quite expensive in their day, especially when you consider the cost of developing all of the technology over a couple of decades. However, the space race and the competition gave motivation so that people (in general) were more willing to spend more money on it to get the job done.

It is that sort of motivation that is really lacking today. If that motivation were reawakened in the general public, there would be a lot more funding opened up (both public and private).

Kimball Kinnison

 

The real question is do we really need more motivation as a society to do these things.

Economically speaking, whatever resources we use to go to space are resources that we could not use here on earth. You have to examine the reasons for human space travel. If it is expanding scientific frontiers, unmanned robots can in most cases do almost anything a human could do. If it is making our species another home in case something happens to earth, I am not sure how you can expect to do that with chemical rockets. If it is for economic gain, again the only way to make money is to get really rich people to take joy rides. We don't have to send people to Mars before we figure out how to do it cheap. Just because we can do it with today's technology doesn't mean we should. It is much more cost efficient to spend that money on R&D that will help us do things better in the future.

Don't get me wrong, I love space travel, I have been to both Kennedy and Johnson space centers, and in middle school my class did some kind of space simulation. If I was a billionaire, I would probably buy a rocket trip myself, but on a public policy level I don't see interplanetary space travel as something that we need to do. I see much more potential in developments in the human genome and computing realms.

 

My point about technology is that there hasn't been a replacement for the chemical rocket. We have 60 plus years of refinement of the same basic technology, but that sets the basic range of costs for launching stuff into orbit and beyond.

And unless a space elevatr becomes a reality there never will be a replacement for chemicla rockets. Nothing else gives enough "umph" to get you off the Earth barring some way to counteract gravity. For now and the forseeable future chemical rockets are the way to go and they will be the way to go for any near Earth operations unless high thrust electric engines can be made. It is possible to use multiple ION engines for transit, but the system use to power it must be compensated for. A small nuclear reactor could clear that up I suppose, but there is nothing primitive about chemical rockets. NASA is working on a way to use the pre-burn part of the rocket reaction so as too increase Isp by two...double the work for the same amount of fuel or half the fuel for the same amount of work. A hydrogen/oxygen rocket would get an Isp of 900 instead of 450.

Individuals may be motivated, but I was referring more to society in general.

The moon landings were quite expensive in their day, especially when you consider the cost of developing all of the technology over a couple of decades. However, the space race and the competition gave motivation so that people (in general) were more willing to spend more money on it to get the job done.

It is that sort of motivation that is really lacking today. If that motivation were reawakened in the general public, there would be a lot more funding opened up (both public and private).

If history were somehow different we might have half a trillion dollars going to space travel rather than the military but that is not the case. Those who are motivated in the private sector are hard at work with the funding they need. The rest of society will have to be patient while the rich go often enough to bring launch costs down.

If it is expanding scientific frontiers, unmanned robots can in most cases do almost anything a human could do.

It is just more expensive to send humans. And right now robotic missions can do good science but are very limited.

If it is making our species another home in case something happens to earth, I am not sure how you can expect to do that with chemical rockets.

As I noted unless high thrust electric systems of some form can be created chemical rockets are the way to go. The European probe that just went to the Moon this last year was Ion powered and took many months to get there. A chemcial boost would have made that a trip measrued in days.

If it is for economic gain, again the only way to make money is to get really rich people to take joy rides.

That is what is happening. I should note too that though making money is a good thing to the rich guys developing all of this their motivations are not just centered around making cash. Money is a necessary tool.

We don't have to send people to Mars before we figure out how to do it cheap.

We won't send anyone to mars unless it is far cheaper than a NASA price tag will be. Even NASA will have to budget very carefully the way they have to operate.

It is much more cost efficient to spend that money on R&D that will help us do things better in the future.

R&D is important but at some point you have to build a thing and use it or else you make no real advancement.

If I was a billionaire, I would probably buy a rocket trip myself, but on a public policy level I don't see interplanetary space travel as something that we need to do.

Ah, but I can think of nothing more important than space exploration and exploitation(exploitation in a positive sense).

 

Yep. I'd far rather see $1 trillion spent on global warming and energy conservation than on a mission to Mars. A Mars mission might be very comparable to the cost of an Iraq war, with goals/benefits at least as questionable.

Again, my sense of it is that the unnecessary intervening moon mission is more evidence that we are not going to Mars. A moon mission will drain away public interest in space exploration so that any post-lunar plans will likely be axed.

If we were serious about going to Mars, we'd go to Mars, not make plans to stop off at the moon.

 

The Moon is a world unto itself with resources galore.

 

Ah, but I can think of nothing more important than space exploration and exploitation(exploitation in a positive sense).

This is where I think you need to take your blinders off. This world we live on had more than enough resources to provide for our most basic needs for just as long as we have lived here already. Solving the world's problems of war, poverty, hunger, disease, climate change, education, and prevention of natural disasters are all more important than space exploration. If we are looking for new resources, the sea floor has just as much if not more potential as the moon. Space is very important, but it is at its most useful when it helps us look back on ourselves.

 

This is where I think you need to take your blinders off.

I see very well thank you.

This world we live on had more than enough resources to provide for our most basic needs for just as long as we have lived here already.

By what standard? If all the world's wealth and food were distributed evenly we would all be in poverty.

Solving the world's problems of war, poverty, hunger, disease, climate change, education, and prevention of natural disasters are all more important than space exploration.

Except that permenent solutions to those problems are not realistic. We will always have to deal with these things one way or another. Halting space exploration does not solve these problems at all and in fact can help reduce these problems.

If we are looking for new resources, the sea floor has just as much if not more potential as the moon.

Except that technologically speaking it is not as easy getting resources from the depths of the oceans.

Space is very important, but it is at its most useful when it helps us look back on ourselves.

I don't know what that means but I do no that there are enough resources off the Earth to sustain quadrillions of people for many billlions of years.

 

One way to colonize the universe, to sort of paraphrase Kurt Vonnegut, would be to grab all the leftover frozen fertilized eggs from infertility clinics around the country and just shoot them off into space in every direction.

 

No offense, K_K, but it's partially this sort of moral browbeating that makes me resist spending more money on NASA.

I don't especially give a rat's behind about NASA or about putting a man on Mars. I don't really think the Apollo missions were all that impressive (except on a level of technological innovation and personal courage) or important, and I don't consider them a "giant leap for mankind," and I'm not going to have any regrets if I die an old man without man ever having returned to the moon or set foot on Mars. I don't have any kind of emotional investment in the space program. I don't get chills watching the Neal Armstrong footage, I don't feel sad that we haven't gone back, and I don't feel like its so important to be chasing our supposed destiny among the stars.

I just don't think it's that bloody important.

What galls me the most, though, is the way people have of talking about it like I have some sacred, solemn duty to give a crap about it, especially since they don't have any real reasons other than "because it's important" and "man's eternal quest to see what's over the next hill, blah blah blah." At this point in my life, I kind of get a sadistic kick out of seeing NASA geeks bleat and squeal about setbacks and budget cuts and whatnot, just because their obnoxious sense of entitlement and "higher purpose" bugs me so.

It's not that I'm anti-science, it's just that I think the same amount of money could be better spent on other areas of science. It's not that I'm anti-exploration, I just think that the deep ocean is both more important and more interesting, and that space exploration is better served by unmanned missions and things of that nature than by sending canned primates to Mars. That's not likely to change, and I don't think your cause is helped by getting on your moral high horse and essentially blaming people like me for not making your little childhood astronaut fantasies come true.

 

So if we were talking about how wonderful deep sea exploration is you'd leave out all that venom? I mean hell, I've made some heated posts before but good grief, that's a scorcher right there.

 

Wow. Can we say out of proportion to what I posted?

I never said that you had to be emotionally invested in it, nor that it was your duty, or anything like that.

I simply said that if people are motivated, they will support the program, even with higher costs. There are several ways that you can motivated people. The space race was one example of how people when people were motivated, they were willing to accept high costs.

Another way to motivate would be to show the long-term financial benefits (asteroid mining, manufacturing in zero gravity, etc). Another would be to show health benefits (heart treatment in zero gravity or lunar gravity).

The key, though, is to motivate people.

Would you spend $1 billion (if you had it) if you knew you could get $1 trillion in 10 years? Wouldn't that motivate you?

So, get a grip, and get control of yourself. There's not need to post suchvitriol at people when it's you who misunderstood what they were saying.

Kimball Kinnison

 

Sometimes advocates do act as if they don't need to bother even to make a plausible argument for why space exploration should displace critical spending priorities, including similarly expensive projects that are at least as difficult to fund as major space initiatives, for example global warming, finding new energy sources to replace fossil fuels, cleaning the oceans, capping the human population.

 

You're totally right. I was out of line. I apologize to you personally, and the others in this thread.

 

Personally, I would also view knowing how to leave the earth as key for when the time rolls around that the Earth's done for. If we find something heading our way, for example, we don't have any good plans on what we're going to do. Also, one of the uses of being back on the moon that I've heard is to help the search for NEA's so that we have more time to prepare.

In some sense, I view the attitude of ignoring what's out there somewhat akin to, say, not bothering to make sure cars aren't coming when you cross the road because you're making sure you don't trip on any rocks. A lot of the earth-related problems are gradual issues... something from space will put all those problems aside very quickly if we're not prepared.

 

I think the long-term future of the species is possibly the biggest reason to go into space. There's a bit of a head-in-the-sand mentality about how we're going to deal with population growth, water shortages, food scarcity and (to a lesser extent these days) global warming a century or two from now. Unfortunately because those issues don't affect anyone now, it's difficult to deal with them through legislation, which I think is why funding for space exploration is a controversial issue. Its greatest benefits are long term, but you'll have a hard time convincing people to spend money on something they won't be around to enjoy.

 

Personally, I think that argument is looking at the problem backwards. It's not that "The human population is growing so fast that we'll soon destroy the planet and be forced to colonize space." The issue is more that if the population keeps growing we'll eventually face environmental collapse of the planet and with it collapse of the advanced industrial civilization necessary to do the R&D for space travel.