What changes has Obama made to NASA?

[Ryker]

I think it was the entire Communist-flavored iteration of Marxism that killed the economies of Russia and China, but I'm sure we're diametrically opposed on this point.

So if you disagree with twofish, what feature of communism was it that killed the economies then? Because you do realize he did mention one such feature of the "communist-flavored iteration of Marxism", right? You seem to be just tossing the word around without any substance behind your "arguments", and I find it very odd that people in this day and age still see the world as "red" and the rest. I guess the conservative US propaganda really does still hold sway over the fears of Americans.

 

[twofish-quant]

True, but there's nothing fundamentally impossible with some of these concepts.

Fundamentally impossible no. Fundamentally extremely difficult requiring large amounts of expensive research to figure out ways around those issues, yes. For example SSTO is limited by the rocket equation which means that given a specific impulse, you need fraction X of weight in the rocket and fraction Y in fuel.

Sure it takes some really advanced materials and a LOT of them (skyrocketing the costs through the thermosphere, literally), but fundamentally possible.

Which requires $X billion in research with probability Y of success.

But "willpower" on part of the population, means much more funding, which means many more resources, engineers, and possibly even better engineers.

Which then requires an economic system to generate the wealth necessary to get things done.

Okay, what laws of physics? Heat + Oxygen + Fuel = Combustion. Heat is shockwaves in the engine, fuel is injected, oxygen is in the atmosphere. The air heats up and expands in the engine, causing it to leave faster than it entered, causing a net gain in velocity as it travels outwards, and law of conservation of momentum accelerates vehicle forward. How is this impossible?

It's not. Jet aircraft do it all the time. However if you want to go to Mach 25, then you run into the amount of energy that is in the fuels, and then you run into frictional heating. Also, to tell if something is impossible or not, you have to run numbers. In the case of SSTO spacecraft , you have to have materials with a certain level of energy content, a certain weight, and certain structural characteristics.







Can't argue with that. But you can only cheap down space launch so much. And, like I said, if a fully reusable system with a short turnaround time can be developed, then because the supply of lifting ability is going to go so far up, it's going to get a lot cheaper. There's a gruesome limit on turnaround time when you have to re-build the entire, or even just part of, the rocket every time. I'm no expert, but I think I can say just from basics that if a system has a turnaround time of less than a week, it would lower prices drastically, if it has any meaningful lift capacity at all. This is why I like the idea of scramjets so much. With that you simply don't need staging or a huge mass ratio. And the simplicity of the engine means not a lot of maintenance, though the cooling system is a whole different story.

What about something like the White Knight/Spaceship One - type "mothership" configuration? Make a "carrier" aircraft with LOX-RP1 rockets, after MECO it detaches, "orbiter" ascends to orbit, mothership switches to turbofan engines to allow it to fly back to the launch site.
Two stages, though both aren't just reusable, but airplane-like. Perhaps even a practical turnaround time less than three weeks if engineered correctly? Have the orbiter attach to the bottom. No cranes, no V.A.B. assembly, no launchpad, even. Just some maintenance, fill the tanks, line up on a runway and it's ready to fly again, just like that. Forget the idea of big, cylindrical, take-it-around-on-a-crawler rocket that needs a launch tower and launchpad. All that only increases turnaround time and maintenance. What's wrong with making the first stage really airplane-like? A Me-163 with modern fuels and a juiced-up mass ratio? With the orbiter simply having to attach to the underside like an MXY-7, drastically reducing time and complexity of assembly. Except, as opposed to the early rocket-planes, use modern fuels such as LOX-LH2 and/or LOX-RP1. Heck, I just worked out the math and the mass ratios wouldn't have to be far above 3 if it DID use LH2/LOX. About half of the Space Shuttle+ET assembly! With RP-1/LOX it would have to be a little above 7.

- Not a big fan of LH-2. I think it's just crazy to use something that cold. Isn't that a source of a lot of the maintenance needed for the Shuttle, because it has to work with something that incredibly cold? And the Columbia incident was because of the insane insulation needed to keep it at -424 *F!
(meanwhile LOX at -298 *F and RP1 at room temperature.)[/QUOTE]

 

[twofish-quant]

Now currently we are stuck in an energy stoneage with oil based energy. But why does that have to be a restriction of "the laws of physics"?

That's not the problem. If you restrict yourself to any sort of chemical rocket, then you can get a specific impulse of at most about 450 seconds. If you start working on solid nuclear rockets, then you can get Isp up to 1200. With air breathing spacecraft you can get Isp up to 2500 seconds.

Once you have the number of the specific impulse, then you plug those numbers into the rocket equation, and that gives you the limits for what your fuel fraction is, and at that point you start figuring out what you make the rocket out of.

Now you can get rid of the problem by putting the source of the power on the ground. The trouble with that is that we have done enough research in jets and rockets to know what the basic problems are. We haven't done that research in laser powered boosters.

If a new energy source and utilization process is found it won't break "the laws of physics".

The two sources right now are chemical and nuclear fission.

Do you really think the laws of physics forbid us to discover a better energy source that is cheaper, abundant, more efficient, and portable to allow mankind to overcome the current barriers in space-travel?

In the next two decades, yes. If there is some source of energy outside of chemical and nuclear that we don't know about, it's going to be really subtle, and if we haven't found it yet, we aren't going to find it anytime soon.

And if there are no sources of energy, then there are no sources of energy.

Now if you think that the laws of themodynamics don't hold them all bets are off.

 

[chiro]

I'm not Two-Fish but I'll reply, or at least comment, anyways. We're not entirely dependent on oil for all our power. There's Nuclear energy, hydroelectric energy, coal power, natural gas, and of course the less mainstream but ever present solar and wind power. Just to name a few. I highly disagree with saying we're in an "energy stoneage", nuclear power is quiet an accomplishment, and we're on the brink of harnessing FUSION power, that can power a city with the hydrogen in a bucket of water. Cars run on "Oil", a highly processed hydrocarbon solution known as Gasoline, by chemically reacting with oxygen to produce heat and drive an amazingly intricate piston engine, an invention I believe was many, many decades ahead of it's time. In principle, a car engine is far more complicated than a rocket engine. (Though that's hardly true in practice, but it is true for certain rockets.) And, interestingly enough, a piston engine relies on a combustible fuel, so it doesn't have to be a hydrocarbon, it's just those are the most cheap and easily available. Cars (Piston engines) could, theoretically, run on any combustible fluid. Alcohol could be an option. And I'm sure there're more non-oil based combustibles than that, that's just off the top of my head.

A Rocket engine does not use "oil", or any form of hydrocarbon, for it's energy reservoir, unless it's a LOX-RP1 engine (Liquid Oxygen, Rocket Propellant One, a type of Kerosene made specifically for rockets), which is used in cheaper, less complicated launch systems. The Space Shuttle, for instance, uses Liquid Hydrogen and Liquid Oxygen, so did the upper stages of the Saturn-V. The engines in-orbit use a hydrazine/nitrogen-oxide combination. (To be specific, Monomethylhydrazine/Dinitrogen-Tetroxide, used on Space Shuttle Orbital Menuvering engines and the Apollo's Command Module SPS orbital menuvering engine.) The Earliest liquid-fuelled rockets ran on Alcohol or Hydrogen peroxide. Solid Rockets run on ammonium perchlorate, though that's certainly not the only option. By far, in terms of performance, LOX/LH2 is the best oxidizer/fuel combination. In terms of price efficiency... Maybe, maybe not. I don't know and I don't know if anyone knows. If someone knew then I assume every engine would use one or the other, but some engines use one and some engines use the other. LOX/RP-1 has lower performance but is much easier to handle and work with, hence, cheaper. Though because it has lower performance it requires a bigger rocket with more fuel.

I'm sorry, but buzzwords annoy me, and with the whole "green" movement going on, "Oil-based society" and "energy stoneage" really seem more political than scientific.

Now, to reply, we don't use "oil" as our energy reservoir in rockets. Only a very specific fuel out of many different options available use oil, and there's no reason to think of hydrocarbons as low-tech. They're a readily available, cheap, abundant, efficient and portable source of power. Though you're right in that they don't provide as much power as we'd like, though we could always want more power, though spaceflight is very demanding.

Sorry, I'll let Two-Fish answer now...

Thanks for the reply.

I didn't mean to generalize oil as the only source of energy, I was simply trying to point out that the "laws of physics" don't prevent us from overcoming current limitations that we may have.

In terms of the word "energy stoneage", I qualify that with the point that the energy "age" is rather young in our history and for the most part we are at the start of it. I imagine in another hundred years we will look back at the energy "stoneage" just like we look back at the tractors that use oxen to operate.

Also I never mentioned any "green" forms of energy. Personally I think things like biofuels are a joke.

Also what is wrong with "oil based society"? Most of the energy we need comes from oil. Fair enough it doesn't power space vehicles leaving earth, but it damn well powers most of the stuff right here on earth. How the hell is that a buzzword? There are reasons why countries guard their oil and why wars are fought over resources.

Also the truth is that even with technological developments in utilizing oil in more effecient ways, most of the energy in your typical car engine is wasted.

The nuclear fission methods and hopefully the fusion methods is kinda what I'm getting at. Truly in the context of energy with reference to "traditional" forms of energy, you can see the kind of context of talking about when I remark about the "energy stone-age".

 

[twofish-quant]

I think it was the entire Communist-flavored iteration of Marxism that killed the economies of Russia and China, but I'm sure we're diametrically opposed on this point.

Which part of Marxism? Russia in 1950 had state-owned enterprise reacting to centrally planned resource allocations. The US had private enterprises reacting to market prices. Is the problem the state ownership or the centrally planned resource allocations or something else?

Personally, I think that it's the centrally planned resource allocations, which means that you can avoid the problems if you have market prices, even if the corporations are state owned. Which has been the experience of China.

I was talking about physics. Is it actually more efficient in terms of energy? There's an incredible amount of friction from the atmosphere when you plow straight through it at those tremendous speeds. Still, you would have to do a lot of work against the gravitational force with the air-breathers.

The thing about rockets is that you don't have high speeds until you get out of the atmosphere. By the time you are at Mach 10, you pretty much already in a vacuum, which means that you don't have to worry about hypersonic aerodynamics.

 

[twofish-quant]

I was simply trying to point out that the "laws of physics" don't prevent us from overcoming current limitations that we may have.

In what? There are no energy limitations that I can think of in generating a mass consumption society, but we are talking about getting payload into LEO, and in that case you are running against some pretty fundamental constraints. You can think of ways around those constraints, but you can't ignore them.

Also what is wrong with "oil based society"?

The problem is that the supply of crude oil is finite. We've already used all of the "easy oil". We are just going to have to find something else in the next fifty years. No real choice in that. The good news is that there are huge amounts of coal lying around, and if we can figure out a way of having coal power a car, we are set, and we are really close to that. (Burn the coal in power plant, have said power plant power a battery.)

Coal will last us for a few more hundred years, which is enough time to get solar power satellites up, and that will last us until the sun burns out.

 

[D H]

In TEN YEARS, we went from no human having ever gone into space, to landing on the moon. Just two years before that decade, 1957, the first satellite went in orbit. Twelve years before then, the first intercontinental missiles were launched from Peenemünde, the V-2's at Great Britain.

Just because some things were easy in retrospect does not mean everything is easy. You are doing exactly the same thing here as people who say "if we could put a man on the Moon we should be able to do X" (substitute favorite pet project for "X").

I never want to hear "pipe dream" again. All it takes is willpower.

All of the wishing, willpower, and money in the world do not make an idea that is inherently unfeasible, impractical, or uneconomical suddenly become feasible, practical, and economical.

But this is what gets me. Ablative heat shields have survived re-entry on JUPITER at 230 G's, I hardly see how we can't handle mach 4 even at sea level.

The Galileo atmospheric probe was a capsule. It wasn't even a lifting body like the X-38 or SpaceDev's proposed Dream Chaser or Orbital Science's proposed Prometheus vehicle. Even the Shuttle (a delta wing) enters the atmosphere more like a lifting body than like a jet.

Heating of the nose in a hypersonic vehicle is a huge problem. The nose on the X-51 will get up to 1480 °C, and that is for a vehicle whose top speed is "only" Mach 6 (orbital speed is Mach 25). The Shuttle, along with those lifting body reentry vehicles, solve this problem by flying belly-first rather than pointy-end first. This solves two problems: Dumping excess speed, and avoiding having the nose melt off. That is not an option for a vehicle that intentionally flies pointy-end first.

Specific Impulse of 20,000-40,000

Whoa there! what units (is this 20,000-40,000 ft/sec?), and what speed (Isp for an air-breathing vehicle decreases markedly with speed).

After all, we did land on the moon...

Stop that.

 

[Shackleford]

In what? There are no energy limitations that I can think of in generating a mass consumption society, but we are talking about getting payload into LEO, and in that case you are running against some pretty fundamental constraints. You can think of ways around those constraints, but you can't ignore them.
The problem is that the supply of crude oil is finite. We've already used all of the "easy oil". We are just going to have to find something else in the next fifty years. No real choice in that. The good news is that there are huge amounts of coal lying around, and if we can figure out a way of having coal power a car, we are set, and we are really close to that. (Burn the coal in power plant, have said power plant power a battery.)

Coal will last us for a few more hundred years, which is enough time to get solar power satellites up, and that will last us until the sun burns out.

I thought they don't know exactly how crude is formed, that it might not be a "fossil" fuel but rather formed through some other geologic process. It seems to me that the rock cycle would recycle many desirable minerals and possibly even generate crude somehow. If not, they don't know how much crude is actually out there. You don't know if we've used up all the "easy oil." Also, that's the thing - technology dictates what is "easy."

http://www.chron.com/disp/story.mpl/ap/business/7420991.html

D H,

I'm curious. What's your background?

 

[D H]

I tend to agree with you, but in the interests of giving astrophysicists who hate manned space program a far hearing then...

1) A lot of the animus is not directed at manned space flight in general, but specifically project Constellation.

There was a lot of animus within the human spaceflight community against Constellation: Against NASA headquarters for a perceived railroading through of what some thought was a poor design, against Bush for underfunding the program, and against Congress for micromanaging the program and dictating suboptimal approaches.

That said, Bush's initial Vision for Space Exploration concept to get back in the business of sending people beyond low Earth orbit, along with the shift in policy direction from space science back to human spaceflight, was widely perceived in a very positive light throughout the human spaceflight community. "About @#$% time" was the general consensus.

Conversely, I don't know of any astrophysicist that is against the SpaceX program. The reason being is that if that program falls apart it's not going to have any impact on unmanned spacecraft .

They need to rethink that posture for at least two reasons. One is that in the minds of many of the politicians who ultimately fund the space program, the justification for doing space science is that this space science is a precursor for human space activities. The other is that they are looking at the wrong thing. They are doing science, so they should look at how expensive their pet projects are compared to other science programs. Space science comes up very short in this regard. It is very expensive and has a limited return on investment. It is a vibrant human spaceflight program that justifies those expenses.

Astrophysicists aren't experts at politics.

Politics isn't rocket science. It's harder. That's why rocket scientists (and astrophysicists) make such lousy politicians.

Personally, I don't think that you can come up with an argument that makes astrophysicists strong supporters of manned space flight.

They should read history lest they be doomed to repeating it.

 

[elfboy]

nasa is the only hope for space discovery
private sector lacks the funding, safety standards

 

[MattRob]

Thanks for the reply.

[...]

Also what is wrong with "oil based society"? Most of the energy we need comes from oil. Fair enough it doesn't power space vehicles leaving earth, but it damn well powers most of the stuff right here on earth. How the hell is that a buzzword? There are reasons why countries guard their oil and why wars are fought over resources.

[...]

Ah. There's nothing really wrong or that I disagree with in that post. I was under the incorrect impression you were mixing science and politics, but now I see you weren't. Sorry 'bout that. Speaking of mixing science and politics, a major pet peeve of mine (or more specifically, bending science to match political goals)...

So if you disagree with twofish, what feature of communism was it that killed the economies then? Because you do realize he did mention one such feature of the "communist-flavored iteration of Marxism", right? You seem to be just tossing the word around without any substance behind your "arguments", and I find it very odd that people in this day and age still see the world as "red" and the rest. I guess the conservative US propaganda really does still hold sway over the fears of Americans.

I really don't think this belongs in this conversation. I've got quiet a number of strong words against it but this isn't the place for that, let's try to stay on-topic and not rail out against other political views we disagree with or call names...
That's the nice thing about science. At least it tries to be objective, and usually it is very much so.

So, about what I said earlier, is there any fundamental or economic reason why first stage rocket boosters can't be designed more like aircraft? The extremely high Specific Impulse of airbreathing engines should mean that it wouldn't be too hard to have turbofan engines, wings, and minimalistic fuel to return to a landing strip. Sure upfront costs on development and vehicle construction would be high because it's unconventional, but if the goal is to make spaceflight more routine like air flight, why not make it more like air flight? Rocket planes have been around since the early 1940's, at least. (To be fair, with not nearly the Delta-V of any space lift 1st stage boosters...) Why not use a mothership / child aircraft ( spacecraft ) configuration, which has existed since, also, at least WWII. These technologies, unlike current conventional designs, don't require some of the huge logistics or maintenance, though they've certainly had the test of time. Ask any engineer at Virgin Galactic.
Less Logistics and maintenance means shorter turnaround time. Shorter turnaround time means more routine flight, lower prices, and all the goodies that brings.

I've heard it mentioned a few times that rockets are better because they punch through the atmosphere faster. But what if the turbofan engine could be the primary propulsion until it climbs to a high altitude? The mass ratio for a turbofan to climb to ~30,000 feet and later to return to the airstrip would be insignificant, almost. Not to mention a majority of the jet fuel would be used to reach that initial altitude, so it's not there to weigh down the rocket when it fires it's real engines, rockets, whatever kind they be.

Then there's the case of getting an effective mass ratio out of an aircraft design. The shuttle should've proved that's possible, by maintaining a mass ratio of ~6.4 (without SRB's, with ET). External tanks being a technology that has also been around since WWII. I suspect complexity and price of External Tanks could be greatly reduced if they didn't have to hold Liquid Hydrogen. Though that would necessitate a high ~7 mass ratio for each stage, meanwhile LOX/LH2 would only require something around 3.7 - and get this: The Boeing 747 has a mass ratio of 2! 3.7 would really be something...

EDIT: @ D H, Ah, that's meters/second, those are theoretical maximums as opposed to current designs. Current rockets are about at the theoretical maximum of their performance, so perhaps it's not totally unreasonable to suspect scramjets could reach their theoretical maximum within a few decades. And why not remember we did what was impractical, unfeasible, and uneconomic? I think more of the problem with shabby ideas is some being proposed more for an individuals' personal gain or from a business perspective are mixed in with real, objective scientific ideas.

 

[D H]

So, about what I said earlier, is there any fundamental or economic reason why first stage rocket boosters can't be designed more like aircraft? The extremely high Specific Impulse of airbreathing engines should mean that it wouldn't be too hard to have turbofan engines, wings, and minimalistic fuel to return to a landing strip.

Economics. Specific impulse is not the right metric. For the most part the only metrics that count are how big (payload mass to orbit) and and how much (dollars per unit payload mass).

There are exceptions. For example, Orbital Sciences uses its aircraft-launched Pegasus rocket to launch small payloads into space at a high cost per unit mass. This becomes economical for a small payload when the options are to pay full fare on a larger launch vehicle or piggyback as a secondary payload on the launch of a large payload and get into a suboptimal orbit. These exceptions for the most part pertain to small payloads. The goal here is presumably to get large amounts of mass into orbit as cheaply as possible.

High specific impulse is not the be-all and end-all toward achieving this goal. There is a lot to be said for the cheaper, low-tech technologies that have been built for decades. This won't be the case forever, but it certainly will be for at least the next ten years, minimum (and twenty is a better bet).

Ask any engineer at Virgin Galactic.

Ask them what? Virgin Galactic's current plans are to offer sub-orbital flights only. Getting something into orbit is orders of magnitude harder than what Rutan did to win the Ansari X Prize. Virgin Galactic hopes to offer orbital flights someday, but when and how are not specified.

EDIT: @ D H, Ah, that's meters/second, those are theoretical maximums as opposed to current designs.

I figured out what the units were. One of the most common mistakes made by students here (and presumably elsewhere) is ignoring units. That said, those numbers are for low speed only. Look at the chart in post #97. Specific impulse drops markedly with increased velocity. That "theoretical maximum" curve? That's for an engine exhausting into vacuum and with an exhaust temperature of 0K.

-------------------------------------------------------------------

I have no problem with doing R&D into future propulsion technologies. NASA and the Air Force should be doing R&D on lots of different propulsion technologies. You should not take me as a naysayer here. What I do have a problem with is prematurely picking some immature technology as the winner, particularly when that decision is made on political connectivity rather than technical merit. Scramjets are one of those. The amounts of money [strike]spent[/strike] wasted on this technology because it has a lot of political backing is immense. Tens of billions were spent on it with the National Aero-Space Plane program alone.

 

[twofish-quant]

I thought they don't know exactly how crude is formed, that it might not be a "fossil" fuel but rather formed through some other geologic process.

There are people that believe that crude oil is produced by non-fossil processes. Most people in the industry believe that these people are "crackpots."

If not, they don't know how much crude is actually out there.

We have a pretty good idea.

You don't know if we've used up all the "easy oil." Also, that's the thing - technology dictates what is "easy."

"Easy oil" is oil that you can get without technology. We've already run out of that. In the 1930's, you could dig a oil in East Texas, and the oil would just gush out.

That oil is gone. You can do the "dig the oil and collect oil" in Saudi Arabia, but that's going to be gone in the next twenty to thirty years. At that point you have to invest in technology in order to get the oil, and technology is expensive, so we are already at the point that we are spending more and more money to get less and less energy. A Gulf oil platform costs a $1 billion.

The good news is that this creates a lot of good paying jobs for astrophysicists. Also, the good news is that once the oil disappears, it will be an annoyance rather than a giant crash (at least in the US.)

 

[twofish-quant]

Ah. There's nothing really wrong or that I disagree with in that post. I was under the incorrect impression you were mixing science and politics, but now I see you weren't.

I am mixing science and politics. There's no way that you can deal with issues like the space program without mixing science, politics, and economics.

So, about what I said earlier, is there any fundamental or economic reason why first stage rocket boosters can't be designed more like aircraft?

DH has gone through them. People have tried doing it for the last fifty years. So far nothing that is ready for prime time. We should still look for them, but it's nothing that you can take to the bank right now.

And I use "take to the bank right now" in a literal sense. When Boeing needs more money to build the 787, they can go to Wall Street and get money from investors. The important thing about this is that Boeing (or for that matter SpaceX) is dealing with reasonably mature technology, and you can put the numbers in a powerpoint and give it to Wall Street investors, and then argue that there is a reasonable chance that they will make money off the deal.

You can't do that with airbreathing engines right now. Because you can't, you have to rely on government funding, and once you do that, you can't go "lean and mean." If you pour government money into basic research, then in ten years, you might be able to make that presentation to investors, but you can't right now.

But what if the turbofan engine could be the primary propulsion until it climbs to a high altitude? The mass ratio for a turbofan to climb to ~30,000 feet and later to return to the airstrip would be insignificant, almost.

It's not. Airplanes are flying fuel tanks. They can get away with a lot because they don't have to carry oxidizers. The problem is that getting you to mach 0.9 at 6 miles is is pretty insignificant for getting you to mach 25 at 100 miles.

Not to mention a majority of the jet fuel would be used to reach that initial altitude, so it's not there to weigh down the rocket when it fires it's real engines, rockets, whatever kind they be.

Kinetic energy goes v^2. The kinetic energy that you get from a jet aircraft is pretty insignificant and you are then limited by the payload of the jet.

I suspect complexity and price of External Tanks could be greatly reduced if they didn't have to hold Liquid Hydrogen.

If you are holding liquid oxygen, then you have to deal with cryogenic fuels. You can deal with room temperature fuels but those don't have the energy content.

Current rockets are about at the theoretical maximum of their performance, so perhaps it's not totally unreasonable to suspect scramjets could reach their theoretical maximum within a few decades.

If we are talking 2050, then all bets are off. It could be that in 2025, someone figures out a way of making massive amounts of carbon nano-tubes that let's us make space elevators. The discussion here is 2015-2020, and scram-jets are not ready for prime time. If we put money in them then by 2020, we could use them in discussing plans for 2030, or we can find that they just don't work. Scram-jets (and carbon nano-tubes) are disruptive technologies, and those technologies you just can't count on for near term planning.

And why not remember we did what was impractical, unfeasible, and uneconomic?

Because you are looking at the horse from the wrong end.

A 12-year old from 2050 could save me a huge amount of time because they know what technologies worked and which ones didn't. From 2011, we know that rockets work and nuclear airplanes and zip fuels didn't, and that the future was in jumbo jets and not SST's. If you look at people in 1965 with the knowledge of 2011, then of course they were idiots because they were making guesses that ended up being wrong.

I am certain that there is a technology that "couldn't possible work" that will. Unfortunately, I have no idea which of the hundreds of technologies that is. If you put all your money on scram-jets, then that means less money in laser powered rockets, solar sails, carbon nano-tubes, and battery technology.

I think more of the problem with shabby ideas is some being proposed more for an individuals' personal gain or from a business perspective are mixed in with real, objective scientific ideas.

If you ask me the problem with Communism is that they assumed that people would act in different ways than they actually do. *OF COURSE* people will act for personal gain.

If you assume that people don't act for personal gain, you'll end up with a political and economic system that just doesn't work. There are no-doubt people that are self-sacrificing, but people that aren't in it for personal gain, rarely end up in positions of major political or economic power, because they are nice and get eliminated by people that are hungry.

Politicians want votes. Business people want money. Workers want bread and circuses, and scientists (being human) aren't more self-sacrificing than anyone else. Your typical scientist wants funding and glory so that they can papers written. If you get a group of senior scientists together, they'll start gossiping like old women about how they are trying to get funding for their university, and also who is "in" and who is "out".

The problem of getting people to the LEO or the moon is not a scientific problem. We've done it before. It's a business/political problem.

 

[twofish-quant]

"About @#$% time" was the general consensus.

The problem is getting money.

Personally, I don't think that anything will happen until it appears likely that there are going to be red flags spread across the solar system.

They need to rethink that posture for at least two reasons. One is that in the minds of many of the politicians who ultimately fund the space program, the justification for doing space science is that this space science is a precursor for human space activities.

The other thing about manned space programs is that they provide a huge amount of pork. More so than unmanned space programs. Ultimately politicians care about votes and jobs, and scientific research doesn't *directly* produce much of that.

Curiously, Chinese politicians are as scared about votes and jobs as American ones. Chinese politicians don't have to worry about being voted out of office, but they are terrified at the prospect of losing power in a way that is less nice (see Egypt). Ultimately the way that you stay in power is "bread and circuses" and the Chinese government uses its manned space program as part of the circuses part of the equation. And if you can keep someone so busy at work that they don't have time to attend a protest, even better...

They are doing science, so they should look at how expensive their pet projects are compared to other science programs. Space science comes up very short in this regard. It is very expensive and has a limited return on investment. It is a vibrant human spaceflight program that justifies those expenses.

And then you ask what justifies human spaceflight, and my answer is the "college football" argument. If we can get things so that people get into a competition to plant flags in the solar system, I think we'll be a lot better off as a species. People seriously lost interest in manned space flight around the time it became obvious that the US "won."

Politics isn't rocket science. It's harder. That's why rocket scientists (and astrophysicists) make such lousy politicians.

Sometimes. There's nothing that makes an astrophysicist a good politician, but there is also no particular reason an astrophysicist would make a worse politician than a lawyer or CEO. If you had more physics Ph.D.'s that went to work as lobbyists, I think we'd be

They should read history lest they be doomed to repeating it.

The problem is that people have wildly different points of view of history.

 

[MattRob]

I am mixing science and politics. There's no way that you can deal with issues like the space program without mixing science, politics, and economics.

Quoted out of context... :

...(or more specifically, bending science to match political goals)...

It's not. Airplanes are flying fuel tanks. They can get away with a lot because they don't have to carry oxidizers. The problem is that getting you to mach 0.9 at 6 miles is is pretty insignificant for getting you to mach 25 at 100 miles.

The idea is that it would have turbofans so it could fly back to a runway, with a fuel-efficient flight path and good choice of landing site, it wouldn't need to be a "flying fuel tank" because it wouldn't cruise across the Pacific Ocean purely using Turbofans like 747's do, it would just use them to climb. The idea is to take advantage of the fact it already has turbofans, and wouldn't it be more fuel efficient to use turbofans below ~40,000 feet than using rockets the whole way? Once it reaches ~40,000 feet, the mothership could ascend with rockets. There's no reason it can't carry rockets and jet engines. Most airliners carry engines in completely separate modules under the wings. And mixing two different types of engines worked with the B-36 Peacemaker in 1949, it's not exactly a large technical challenge. And wouldn't necessarily have to be limited to ~40,000 feet, the U-2 could cruise above 70,000 feet using turbofans, though I suspect that would require too much performance out of the jet engines for them to remain a modest weight.

If you are holding liquid oxygen, then you have to deal with cryogenic fuels. You can deal with room temperature fuels but those don't have the energy content.

Liquid oxygen and Liquid hydrogen are in entirely different temperature ranges. Liquid Oxygen can be liquid at 90K (-297 *F), but Hydrogen boils at 20K (-423 *F). That's not it, either. Absolute zero is an asymptote, which means that half the temperature is far more than twice as hard to reach. Many metals become brittle well before the boiling point of nitrogen, 77K or -320 *F, so I can only assume it must be a great engineering challenge to find a material that is not only still malleable at the range of Liquid Oxygen, but at twice as cold as that. Then you have to build many, many moving parts out of it, turbopumps, valves, etc. and build the entire rocket assembly out of it, fuel tanks, pipes, and other bits. And finally, icing becomes even more of a problem. The insulation on the ET is only needed because liquid Hydrogen is so cold. If the Space Shuttle used RP-1/LOX, Columbia would not have happened, because much stronger insulation could be used, unlike the foam-like material needed for Liquid Hydrogen.

An aside, to illustrate the difference; You could pour liquid oxygen in a coffee thermos, put the lid on (careful not to screw it on), and it'd take it a day or so to boil off. As for liquid hydrogen, I have yet to ever see or even hear of it being stored in anything other than a thick, double-walled vaccum-insulated container.

If you ask me the problem with Communism is that they assumed that people would act in different ways than they actually do. *OF COURSE* people will act for personal gain.

If you assume that people don't act for personal gain, you'll end up with a political and economic system that just doesn't work. There are no-doubt people that are self-sacrificing, but people that aren't in it for personal gain, rarely end up in positions of major political or economic power, because they are nice and get eliminated by people that are hungry.

Politicians want votes. Business people want money. Workers want bread and circuses, and scientists (being human) aren't more self-sacrificing than anyone else. Your typical scientist wants funding and glory so that they can papers written. If you get a group of senior scientists together, they'll start gossiping like old women about how they are trying to get funding for their university, and also who is "in" and who is "out".

The problem of getting people to the LEO or the moon is not a scientific problem. We've done it before. It's a business/political problem.

I couldn't agree more, but there is a difference in-between pressing an idea solely for political purposes and personal gain as opposed to doing it for the advancement of mankind, etc. The whole debate over the existence of altruism aside, there's a balancing point where most people fall, and scientific endeavors done because someone wants to make money aren't as successful as ones purely for the sake of science. If it's done to make money, then there are plenty of ways to "succeed" that would actually be failing when it comes to developing the technology. I.e, you don't need the technology to work, you just need to get money out of the whole deal (I believe this is called a scam.). It doesn't matter what technology it is, it's development can be marred in this way.

 

[twofish-quant]

The idea is that it would have turbofans so it could fly back to a runway, with a fuel-efficient flight path and good choice of landing site, it wouldn't need to be a "flying fuel tank" because it wouldn't cruise across the Pacific Ocean purely using Turbofans like 747's do, it would just use them to climb.

Pegasus does something like that. The useful thing about using an airplane as a first stage is that for light satellites you don't to create much special infrastructure, and you can launch on a moments notice. Which becomes really, really important if you are in the middle of a shooting war.

The trouble is that you save money only because the aircraft you are using is commercial off-the shelf aircraft, which limits your payload. If you want to launch something that can carry a human being then you have to develop the carrier aircraft, at which point your costs go crazy.

Many metals become brittle well before the boiling point of nitrogen, 77K or -320 *F, so I can only assume it must be a great engineering challenge to find a material that is not only still malleable at the range of Liquid Oxygen, but at twice as cold as that. Then you have to build many, many moving parts out of it, turbopumps, valves, etc. and build the entire rocket assembly out of it, fuel tanks, pipes, and other bits.

But this is a been there, done that sort of thing. We have the technology to work with liquid hydrogen, and it's not particularly difficult.

I couldn't agree more, but there is a difference in-between pressing an idea solely for political purposes and personal gain as opposed to doing it for the advancement of mankind, etc.

Less than you think. A lot of people that do altruistic things for the advancement of mankind are doing it so that they get the glory for doing something for the advancement of mankind.

The whole debate over the existence of altruism aside, there's a balancing point where most people fall, and scientific endeavors done because someone wants to make money aren't as successful as ones purely for the sake of science.

I strongly, strongly, strongly disagree. Projects that have no economic or political payoff tend to go nowhere at best or at worst become topics of rather petty political politicking. You really need some economic or political goal in order to "get stuff done."

If it's done to make money, then there are plenty of ways to "succeed" that would actually be failing when it comes to developing the technology.

And that's great. If you can generate wealth without developing new technology, that's wonderful. For LEO, we just have to stop thinking of things in terms of technology development and more in terms of a "space trucking" company. If you have some engineers start a trucking company, they'd be spending decades on AI robots that don't work, meanwhile the business guy just hires some strong people off the street to put the stuff into trucks.

Why the heck are we talking about spaceplanes when we have rockets.

I.e, you don't need the technology to work, you just need to get money out of the whole deal (I believe this is called a scam.).

It's called getting something done. Sometimes high technology is useless or counterproductive. Space travel is a case in point. We want to get stuff into low Earth orbit as cheaply as possible. If you are in this for "science" then you end up spending huge amounts of money on things that don't work, which means that you end up getting nothing done. Not that there is anything necessary wrong with that.

If you don't need technology to generate wealth, then don't use technology. McDonalds is an exteremely profitable business and they don't use much in the way of technology.

If you look at this as a business problem. You don't care if the solution is high tech, low tech, or no tech. You can just look at the Russians and copy what they do. For getting stuff into space, there isn't a need for massive technology development since the technology to do it is fifty years old. It's a process/efficiency/business problem, which is the type of thing that research labs and scientists are just horrible at.

It doesn't matter what technology it is, it's development can be marred in this way.

But what has killed the space program is the idea of technology for the sake of technology. The problem with high-risk technology is that sometimes it just won't work.

 

[MattRob]

But this is a been there, done that sort of thing. We have the technology to work with liquid hydrogen, and it's not particularly difficult.

But there's a reason SpaceX uses LOX-RP1. It's not too difficult, but whether it's cost-effective or not is questionable. Is the performance increase worth the increase in development AND construction costs, massively increased maintenance and complexity, which in turn makes more room for more accidents, as well as making the entire system more expensive? Apparently SpaceX doesn't think so.

Less than you think. A lot of people that do altruistic things for the advancement of mankind are doing it so that they get the glory for doing something for the advancement of mankind.

[...]

I strongly, strongly, strongly disagree. Projects that have no economic or political payoff tend to go nowhere at best or at worst become topics of rather petty political politicking. You really need some economic or political goal in order to "get stuff done."

I purposely stayed off of the Altruism debate, that's more philosophical/personal... I didn't mean do projects with no economic payoff, if it makes services easier, makes society run smoother, then it will have economic payoff in a free market/capitalistic society. If it makes spaceflight cheaper, it will make money. But there's a difference in-between doing that and just making personal profit.
If the only objective was personal profit, I would be going into business, not a technical field.
If society was purely bent around profit, there would be a lot less science as a whole. I'm not saying science doesn't have applications, but a lot, and I do mean a lot of it would get cut out out of existence.

For example, how does studying the composition of distant stars make money? So should we cut off all of astronomy because it has no political or economic payoff? Aside from loose technological connections, the only things it's really turned out from a business perspective is pretty pictures that sell well. If everything was just to make a profit, say good-bye to any advanced physical research into the fundamental structure of the universe, 95% of astronomy, all unmanned space exploratory probes, and a lot more than that. Money could be better made by business ventures than space probes or learning a more advanced scientific understanding. This is why a government agency is needed to fund most of this, and government spending is needed to keep science going, aside from publicity donations or applied science. Pure science has no economic/political payoff in the short term, just like advanced space propulsion research. They're both pure science, only at least space propulsion is more promising for applications. I.e., from a purely economic perspective, these wacko space ventures have more right than pure science.
(Pure science meaning science for the sake of science, i.e. studying the expansion of the universe, trying to understand the fundamental structure of the universe, etc.)

And that's great. If you can generate wealth without developing new technology, that's wonderful. For LEO, we just have to stop thinking of things in terms of technology development and more in terms of a "space trucking" company. If you have some engineers start a trucking company, they'd be spending decades on AI robots that don't work, meanwhile the business guy just hires some strong people off the street to put the stuff into trucks.

Why the heck are we talking about spaceplanes when we have rockets.
It's called getting something done. Sometimes high technology is useless or counterproductive. Space travel is a case in point. We want to get stuff into low Earth orbit as cheaply as possible. If you are in this for "science" then you end up spending huge amounts of money on things that don't work, which means that you end up getting nothing done. Not that there is anything necessary wrong with that.

If you don't need technology to generate wealth, then don't use technology. McDonalds is an exteremely profitable business and they don't use much in the way of technology.

If you look at this as a business problem. You don't care if the solution is high tech, low tech, or no tech. You can just look at the Russians and copy what they do. For getting stuff into space, there isn't a need for massive technology development since the technology to do it is fifty years old. It's a process/efficiency/business problem, which is the type of thing that research labs and scientists are just horrible at.
But what has killed the space program is the idea of technology for the sake of technology. The problem with high-risk technology is that sometimes it just won't work.

There's truth to doing whatever makes money, that's why it's nice NASA is working with private space companies now, but at the same time we should continue research into new technologies. Sure a new technology doesn't make money right now, but in the long run new tech does make things cheaper. You can drive down costs by making a rocket simple, but only so much. If you can develop a more efficient way of getting into orbit, then the costs can go even lower. If mankind is to ever really progress, we need those costs to go down. Manned spaceflight isn't purely economic, it's also about our progress and long-term survival as a species.

The problem is I-want-money-now type thinking is too common for people to really see something this grand and long-sighted, where a profit is to be earned it should be earned in spaceflight, but the ultimate goal is also building a better future for mankind and civilization as a whole. I expect that sort of visionary approach to be laughed at, but can anyone who has lived through Mercury, Gemini and Apollo really say it was a waste of money? People want progress. Technological as well as political.
If it means taking nine steps back for every ten steps forward, then it's still ultimately worth it. There will be a payoff to that technology for the sake of technology, just as sure as there's a payoff to knowledge for the sake of knowledge. They're both science for the sake of science.

 

[chiro]

Also one should note that typically the cutting edge of pure science (be it mathematics, physics, chemistry etc) will often be in an engineering curriculum half a century (or maybe even less) later.

Even pure maths fits in this category (at least science even if pure is applied!). The best example I can think of in pure maths (besides cryptography) is with wavelets where the FBI uses them to store and detect matches with source fingerprints to other fingerprints in the database.

I think the nine steps back for every step forward is a good description of what happens in research of any kind. We have initial romantic views about accomplishing something but typically the progress comes after many many failed dead ends and by the end the researcher (or team thereof) is probably just happy to get some positive result and is probably exhausted by this time.

One good thing is that many entrepreneurs aren't focused on money, but instead by a burning passion to get something done. They stick it out and carry on with minimum capital and they have a kind of blind optimism that a money hungry investor would not have.

Fads and trends will always come and go, but I have no doubt that entrepreneurs with the right vision, tenacity, and hard work will face the problems that are being talked about and go forward with their venture anyway regardless about the projections that even experts put out there.

I understand when people say the problem is a financial, political, economic etc problem, but that's what entrepreneurs do: they start with a goal and they face problems, and they problem solve to get around them. People that solve problems reap their rewards and when the problem is something that was faced by segments of society, then they rightfully benefit a lot more.

If you got the right team of problem solvers in one room, you would do quite a lot and I dare say you could even surprise yourself with what you can accomplish.

 

[twofish-quant]

Is the performance increase worth the increase in development AND construction costs, massively increased maintenance and complexity, which in turn makes more room for more accidents, as well as making the entire system more expensive? Apparently SpaceX doesn't think so.

True, but in another context it might make sense.

If the only objective was personal profit, I would be going into business, not a technical field.

Sure, but when you talk about personal stuff, money isn't everything. For me, I went into physics because it was fun and interesting. Not much to do with money, but it's still quite selfish anyway. Also, I like solving problems. At various points in my career, I got stereotyped into "pure technical" roles which I absolutely hated because I find that business and political problems are as interesting as physics ones.

One other thing is that if you just think about technical problems, you just aren't going to get that much done.

If society was purely bent around profit, there would be a lot less science as a whole. I'm not saying science doesn't have applications, but a lot, and I do mean a lot of it would get cut out out of existence.

If you look at what gets funded and what doesn't, it's mostly around profit. People fund science because scientists have been able to make the argument that if you spend money on science, you get useful toys out. If you want to see what the science would look like without this argument, look at a German philosophy or Medieval literature department.

For example, how does studying the composition of distant stars make money?

Well. it so happens that the energy mechanism that powers distant stars also is used in the 2000 or so hydrogen bombs that the US uses to maintain world domination. If it turned out that no one in the US knew how to make a hydrogen bomb, and lots of people in Iran did, bye, bye Saudi oil fields.

One thing that I saw first hand after the collapse of the Soviet Union, was the US paying large amounts of money to Russian astrophysicists to work in the US. Russia was broke, and the fear was that if the US didn't come up with money then the North Koreans or the Iranians would.

One of the things that a scientist can do is to go to a politicians and say "Give me money to work on stuff that I'm interested in. I can't tell you how you are going to make money from it. I don't even know how you are going to make money off of this. But based on past experience you will get money and power from this."

Astrophysicists can do this. German philosophers can't. That's why astrophysicists get money, and German philosophers don't.

So should we cut off all of astronomy because it has no political or economic payoff?

1) It's false. Stop funding astrophysics, and in a decade or two, no one in the US will know how to build an H-bomb

2) It's not a should question. If I can't go to a politician or voter and explain to them why they should give me their money, then they won't. It so happens that astronomy does have huge political and economic payoffs.

If everything was just to make a profit, say good-bye to any advanced physical research into the fundamental structure of the universe, 95% of astronomy, all unmanned space exploratory probes, and a lot more than that.

Nope. If you look at senior astrophysicists, they spend a good chunk of their time and effort going off to various people trying to "sell" astronomy. They've done a pretty good job at it. You sell something by playing on basic human emotions. Love, fear, anger.

Pure science has no economic/political payoff in the short term, just like advanced space propulsion research.

Pure science has a lot of economic/political payoff. The problem is that the payoff is too distant and uncertain to attract private funding.

But when we are talking about "space trucking" that's not in that arena.

(Pure science meaning science for the sake of science, i.e. studying the expansion of the universe, trying to understand the fundamental structure of the universe, etc.)

And the US started putting massive amounts of money in this starting in the 1940's to build better bombs.

Sure a new technology doesn't make money right now, but in the long run new tech does make things cheaper.

If you have a working economic system, which the Russians didn't.

You can drive down costs by making a rocket simple, but only so much.

Eat the low hanging fruit first.

I expect that sort of visionary approach to be laughed at, but can anyone who has lived through Mercury, Gemini and Apollo really say it was a waste of money? People want progress.

People don't necessarily want progress. Progress is sometimes annoying. Also being a visionary is fine, but you have to realize that you have to work with people with different visions. Getting enough people to agree with you on something is the "political problem."

There will be a payoff to that technology for the sake of technology, just as sure as there's a payoff to knowledge for the sake of knowledge.

Not necessary. See Russia. Great scientists. Lousy business people.

They're both science for the sake of science.

You are contradicting yourself. You happen to believe that putting money in science will ultimately help society. Personally I agree, but that's "science for the sake of helping society." The problem that you will run into is that a lot of problems just aren't science problems, they are political/economic/social problems, and if you ignore politics/economics/sociology, you'll end up with "pure science" which ends up being rather useless.

The Russians were really, really good at pure science. Best physicists in the world. The problem was that they also had a broken political and economic system which means that all of the breakthroughs in science didn't go to make better consumer goods.

 

[D H]

The idea is that it would have turbofans so it could fly back to a runway, with a fuel-efficient flight path and good choice of landing site, it wouldn't need to be a "flying fuel tank" because it wouldn't cruise across the Pacific Ocean purely using Turbofans like 747's do, it would just use them to climb.

Won't work, at least not for any sizable payload. There is something to be gained for launching from high altitude, but the losses are huge. An aircraft capable of serving as the launch platform for getting people into space would have to be orders of magnitude larger than the largest airplane. Orbital does use a similar concept with its Pegasus rockets, but those are rather small rockets. Pegasus is very expensive in terms of payload mass to orbit and in terms of cost per kilogram to orbit.

 

[D H]

We have the technology to work with liquid hydrogen, and it's not particularly difficult.

Liquid hydrogen is an absolute bear to work with compared to liquid oxygen. Liquid hydrogen is much colder than LOX and the tiny size of the hydrogen molecule makes LH2 systems prone to leaks. Issues with the liquid hydrogen system have caused ten different Shuttle launches to be delayed, starting with STS-30 in 1989, and ending with STS-133 (which hasn't launched yet). Liquid hydrogen is a high-tech fuel, complicated in the case of the Shuttle with its side-mount design.

The apparent improvement in specific impulse offered by LH2 as a fuel is to some extent illusory. Hydrogen's low density and cryogenic nature mandate a much larger, more massive fuel tank than is needed for non-cryogenic fuels. This reduces, but does not eliminate, the advantage of LH2 as a fuel.

 

[MattRob]

@ An aside to D H, I have personal experience with that second part. Flew out to the Cape to see STS-133 launch. After going to Kennedy at least four times (one of which involved waiting in a rainy parking lot at 4am...), they had to push the whole launch back to February. Well, now it's February and I'll be leaving to Florida again tomorrow afternoon.

Sure, but when you talk about personal stuff, money isn't everything. For me, I went into physics because it was fun and interesting. Not much to do with money, but it's still quite selfish anyway. Also, I like solving problems. At various points in my career, I got stereotyped into "pure technical" roles which I absolutely hated because I find that business and political problems are as interesting as physics ones.One other thing is that if you just think about technical problems, you just aren't going to get that much done.

The United States is nothing but the collection of 300,000,000 individual lives. And apparently everybody in the U.S. is willing to spend tens of times more money on Oreos than spaceflight, if you look at how the economy is.

I didn't say don't worry about economics. Chiro's post is a fine example of my point.

If you look at what gets funded and what doesn't, it's mostly around profit. People fund science because scientists have been able to make the argument that if you spend money on science, you get useful toys out. If you want to see what the science would look like without this argument, look at a German philosophy or Medieval literature department.

Well. it so happens that the energy mechanism that powers distant stars also is used in the 2000 or so hydrogen bombs that the US uses to maintain world domination. If it turned out that no one in the US knew how to make a hydrogen bomb, and lots of people in Iran did, bye, bye Saudi oil fields.

One thing that I saw first hand after the collapse of the Soviet Union, was the US paying large amounts of money to Russian astrophysicists to work in the US. Russia was broke, and the fear was that if the US didn't come up with money then the North Koreans or the Iranians would.

One of the things that a scientist can do is to go to a politicians and say "Give me money to work on stuff that I'm interested in. I can't tell you how you are going to make money from it. I don't even know how you are going to make money off of this. But based on past experience you will get money and power from this."

Astrophysicists can do this. German philosophers can't. That's why astrophysicists get money, and German philosophers don't.

And the only problem with spaceflight is there isn't a long history of past experience. Projects are expensive and take a long time, so this history won't develop for a long time, and in order for it to develop at all people need to be able to say that. It's sort of like a Catch-22, making it difficult for government, and nigh impossible for private. Also, these arguments for getting useful tools out of these projects in the long run - can all be applied to defend advanced propulsion research in manned spaceflight.

Nope. If you look at senior astrophysicists, they spend a good chunk of their time and effort going off to various people trying to "sell" astronomy. They've done a pretty good job at it. You sell something by playing on basic human emotions. Love, fear, anger.

Manned spaceflight -> Hope.

Pure science has a lot of economic/political payoff. The problem is that the payoff is too distant and uncertain to attract private funding.

But when we are talking about "space trucking" that's not in that arena.

My reply is simply that there's a department for getting the job done, and a department for improving the job in the future. Computer companies don't just either sell computers or make them better, they sell them and make them better. There's no reason "space trucking" shouldn't be in that area.

Eat the low hanging fruit first.

Low hanging fruit being what SpaceX is doing. Researching advanced designs would be planting crops. You can get by fine without planting crops, to some extent, but planting crops makes the difference in-between a primitive nomadic society and civilization as we know it.
You can get by without it, but to really thrive you have to invest in the future. Even if it isn't quiet as easy as we thought, the future of a plentiful, easy harvest everyone can enjoy is sure to come if we keep on planting. But only if we keep on planting.

You are contradicting yourself. You happen to believe that putting money in science will ultimately help society. Personally I agree, but that's "science for the sake of helping society." The problem that you will run into is that a lot of problems just aren't science problems, they are political/economic/social problems, and if you ignore politics/economics/sociology, you'll end up with "pure science" which ends up being rather useless.

The Russians were really, really good at pure science. Best physicists in the world. The problem was that they also had a broken political and economic system which means that all of the breakthroughs in science didn't go to make better consumer goods.

My point is that science for the sake of science will ultimately help society. I think that's something we can all agree on, but I go a step further and say: Especially when it comes to designing vehicles to make LEO cheap. And I'm not saying to ignore the current economic/political situation, we still need SpaceX and their cheap LEO systems, but we also need to keep looking at how we can make manned spaceflight even cheaper than what's possible with current technology.

You don't put all of your money into improving your product or selling it. You put money into both. And there's no reason we shouldn't do the same for manned spaceflight, it's a product like any other. It's a product currently being paid for by the people of the United States as a whole. (NASA, specifically) It's a product that should ultimately one day be much cheaper and more easily available than it can ever be with current technology. The point of the "improving the product" is being underplayed. The "selling it" is what NASA is doing with SpaceX. If we are to ever achieve the ultimate dream of human spaceflight, then the only way to do it is to invest in the future. You can't expect to reap a harvest if you haven't planted any corn. It will never come if we just sit back without investing in it and expect it to happen on it's own.

 

[twofish-quant]

The United States is nothing but the collection of 300,000,000 individual lives. And apparently everybody in the U.S. is willing to spend tens of times more money on Oreos than spaceflight, if you look at how the economy is.

And that's because they get bombarded by commercials about how good Oreo's taste. Get some money, hire some of the people that sell Oreo's and have them sell manned space flight.

And the only problem with spaceflight is there isn't a long history of past experience.

We've been doing it for fifty years. That's plenty of experience.

Projects are expensive and take a long time, so this history won't develop for a long time, and in order for it to develop at all people need to be able to say that. It's sort of like a Catch-22, making it difficult for government, and nigh impossible for private.

From a project management standpoint, sending people into LEO isn't any worse than designing an airliner, rolling out a new car, drilling for oil, or putting out microchips. Private companies are willing to spend billions of dollars doing those things.

Also, these arguments for getting useful tools out of these projects in the long run - can all be applied to defend advanced propulsion research in manned spaceflight.

Which I'm all in favor of. What I'm against is using untested technology to do things in the next ten years. When making plans out to 2020, we have to use tried and true technologies and then do what we can to beat down the cost of getting into LEO. Once we get to 2020, we can see what technologies are promising, and then figure out what to do for the next ten years.

I have nothing against blue sky research. What I'm very strongly against is holding the US space program hostage to that sort of research. I'm also very strongly against "not invented here." One thing that helps the Chinese space program is that people in China are not afraid to copy the US or Russia when the US or Russia just does things better. One problem that the US has to realize is that it's not number one in manned space flight (Russia is), and China has a plan that "makes sense." India should get in the game before the decade is out.

My point is that science for the sake of science will ultimately help society. I think that's something we can all agree on

You and I agree on this. Other people might not. The other thing about money is that it's a good sign to see what people really believe. Someone might *say* they they are for science, but talk is cheap. You find out what people really believe when you see what they are willing to pay for, and people don't believe that science will help them that much based on funding levels.

And in any case once you argue that you should be funded for the sake of helping society, you then have to ask questions about *which sciences* should be more funded. One dollar that goes into space research means less money that goes into biotech research.

And I'm not saying to ignore the current economic/political situation, we still need SpaceX and their cheap LEO systems, but we also need to keep looking at how we can make manned spaceflight even cheaper than what's possible with current technology.

Sure, but I'm saying that none of that will matter before 2025, and if you ignore the short term, you'll never get to the long term. The big danger is that if the US doesn't keep a presence in space right now, then it's not going to have the technological infrastructure to do anything with advanced propulsion even if we find something.

And then there is a good chance that we'll roll snake-eyes and there *won't* be any advanced propulsion techniques that work. If you have things like SpaceX, then the US is still in the game. If you ignore those then the US has nothing.

And then it boils down to dollars and cents. If you want to spend $10 million on scramjet research, that's great! If you want to spend $10 billion, then we have a problem.

The "selling it" is what NASA is doing with SpaceX. If we are to ever achieve the ultimate dream of human spaceflight, then the only way to do it is to invest in the future.

We've been sending people into space for fifty years. We've achieved human spaceflight. The question is now what.

Also, Americans have this unfortunate habit of thinking that the US is the world. I have no worries about *human* spaceflight. Russia and China have sent people in LEO. China apparently has a plan to get people to the moon. India is planning on something before the end of the decade. And there are about a dozen nations with the technological infrastructure to send people into LEO if they wanted to.

I'm very worried about *American* manned space flight. That's a totally different issue.

You can't expect to reap a harvest if you haven't planted any corn. It will never come if we just sit back without investing in it and expect it to happen on it's own.

You have me confused with someone else.

I'm not saying that we shouldn't spend money on weird technology. I'm saying that we shouldn't expect to weird technology to rescue the US manned space program. Any advanced propulsion system is not going to be ready for prime time before 2020, and when we first use scramjets, we should expect some things blowing up from time to time.

What I'm saying is that advanced propulsion will not save the US manned space program.

 

[D H]

My reply is simply that there's a department for getting the job done, and a department for improving the job in the future. ... Low hanging fruit being what SpaceX is doing. Researching advanced designs would be planting crops.

NASA does do research into new propulsion techniques. Neither twofish nor I have said that NASA should stop doing that. What both of us have said is that it is a very bad idea to prematurely push a new technology as the one big hope for the future.

Trans-atmospheric vehicle / scramjets is, IMO, the prototypical example of a new technology pushed before it was ready for prime time. Absolutely huge amounts of money have been spent on this technology, more than ten billion dollars for the X-30 National Aero-Space Plane program alone, with very little to show. (Not quite: The X-30 research did show that getting past Mach 10 would be extremely hard; getting past Mach 17, not possible.)

On this forum and on others, people perpetually ask "Why isn't NASA using technology X," substitute "technology X" for scramjets, nuclear propulsion, laser propulsion, space elevators, launch loops, rail launchers, etc. (pick your poison; they've all been discussed). The answer is that while NASA is doing/supporting research into all of these technologies, not a single one of these is anywhere close to being ready for prime time. Most of these never will be ready for prime time. Which ones will be? There's no telling. A quote by Einstein is very applicable here: "If we knew what we were doing it wouldn't be called research, would it?"

You mentioned Space X. Space X was founded in 2002. It flew its first rocket in 2008, and only just recently flew its first rocket capable of going to the Space Station. Note that this latter flight was more than two years late; replicating 50+ year old rocket technology is not as easy as Musk originally thought it would be. Launching a vehicle with people on it will take a few more years, maybe quite a few more years. That's a ten to fifteen year time span just to bring extremely well-known technology up to snuff, and that is by a hard-nosed entrepreneur who knows very well how to squeeze schedules, people, and pennies.

Think about that last sentence in terms of how long would it take to bring an unknown technology up to snuff by a squishy-nosed government project manager who doesn't have control of the budget and who is subject to undue meddling by NASA HQ and by congresscritters. (Regarding this last term: The general public rates congresscritters as only slight worse than used car salesmen. I have an even lower opinion.)

 

[twofish-quant]

That's a ten to fifteen year time span just to bring extremely well-known technology up to snuff, and that is by a hard-nosed entrepreneur who knows very well how to squeeze schedules, people, and pennies.

The good news is that 1) it's cheap and 2) it's known that it can be done. That means that even with all of the problems, the project doesn't get cancelled. It's costing more and taking longer than expected, but it's still within the founders financial capacity, and since it's their money, they don't have to answer to congresspeople about wasting it.

Think about that last sentence in terms of how long would it take to bring an unknown technology up to snuff by a squishy-nosed government project manager who doesn't have control of the budget and who is subject to undue meddling by NASA HQ and by congresscritters.

And to be fair, NASA HQ and congresscritters are doing their jobs. If you want something done efficiently you have to go "lean and mean." The trouble is that if you are dealing with billions of dollars rather than millions of dollars you just can't go "lean and mean" since you need large numbers of people to track the money and large numbers of people to do bureaucratic/management type things. Big projects like Apollo are really hard because you can't avoid bureaucracy in multi-billion dollar programs, but at the same time, bureaucracy can kill the project.

The trouble is that "production system" and "research system" don't mix. If you really want funding for scram-jets, what you need to do is to go up to Congress and say honestly, "this is pure research, it could by the next big thing, but there is a 98% chance that it will led to nothing useful". For that, you can't get a billion, but you might be able to squezze out $10 million that will let you fund a "lean and mean" skunk-works project. At the end of five years, you can then go back to Congress and say either "we'll we learned that X won't work give us another $10 million to study something else" or "we found that it does work, now give us $10 billion to put this into production."

(Regarding this last term: The general public rates congresscritters as only slight worse than used car salesmen. I have an even lower opinion.)

Curiously enough, I have a much higher opinion of Congress-people. Once you see how the world looks like to them, a lot of what they do makes sense, and I sort of understand and sympathize with how the world looks like to them.

Part of the reason I'm sympathetic to Congress-critters, is that I've had to do "political stuff." If you go up to someone and sub-consciously you are thinking "X is an idiot and I hate him", most people will catch on very quickly and then stop listening to you. This is especially true for politicians that have a sixth sense for what people are *really* thinking, not just want they are saying. If you want to influence someone, you have to at least understand their view of the world.