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Cool. Remember when cars ran on steam? Now, we have hydrogen cars that are more efficient, can generate more power, and the fuel weighs less so it has less to push increasing performance.


Take THAT... and plug in space propulsion.

It's not quite as easy as that.

 Kilkrazy wrote:
It's not quite as easy as that.

This. But keep demonstrating that you don't understand the science and engineering problems involved, and how even with laughably optimistic assumptions (100% perfect efficiency antimatter conversion) the energy requirements are immense and effectively impossible.

(And bonus points for trying to pretend that realism about science and engineering is somehow socialism and trying to live off your money.)

Bonus points for realizing that the drive to achieve something this monumental is anathema to your political viewpoints? I'll take it.



NOTHING is easy, except just lying there doing nothing. Sure, it's not as simple as "lift rock, find alternative fuel source for space travel", but that doesn't necessitate that we should consider what we view as impossible today as prohibitive to seeking out the technologies that will make it possible in the very near future.

There's no need to get personal about it. It's about engineering.

The secret to improving ion drive apparently is to increase the voltage across the anode and cathode grids. This produces higher velocity ions, allowing the engine to use less propellant for the same thrust. There will be an engineering challenge associated with the conversion circuit which ramps up the voltage, and of course the power supply.

Another engineering challenge is to build thrusters which have very long running times, to overcome the low acceleration per second.

The new NEXT thruster is over three times more powerful than the NSTAR unit on the DS1, and has been test run for 51,000 hours (nearly 6 years!)

Assuming a spacecraft with the same overall mass as DS1, the NEXT thruster could presumably accelerate it to about 51.12 Km per second. Probably more, actually, because there would need to be more propellant on board at the start of the burn, but there would be a smaller payload.

Near light speed travel is enough of a task, but faster than light travel is impossible according to the known laws of the universe. The closer you get to the speed of light the more energy you need to expend to continue accelerating until you hit the speed limit for matter at which point you need an infinite amount of energy. There's also the fact that any inhabitants of a vessel would experience its acceleration as G forces, meaning they'd be dead way before they passed even a fraction of the speed of light.

That being said, it would only take a few decades to travel quite a ways across the galaxy using current propulsion technologies, but then we're talking about generation ships on a one-way trip. Interstellar travel the way we know it from Science Fiction is just not going to happen, barring some godlike development in manipulating physical reality itself.

Assuming that we survive long enough before going extinct or entering a new dark age (both of which are eminently possible and likely) mining the asteroid belt and establishing a permanent presence on other planets in our solar system is not outside the realm of possibility, but we're still talking about the single greatest undertaking that mankind has ever applied himself to by an order of magnitude.

 Just Tony wrote:
Bonus points for realizing that the drive to achieve something this monumental is anathema to your political viewpoints? I'll take it.

Yep. My political viewpoint prioritizes respect for science and engineering, which makes it poorly suited to native dreaming about how we can do effectively impossible things if we just dream hard enough.

Ps: even the Soviets had a space program and held up scientific accomplishments as a point of national pride, so your ridiculous political argument doesn't work at all.

NOTHING is easy, except just lying there doing nothing. Sure, it's not as simple as "lift rock, find alternative fuel source for space travel", but that doesn't necessitate that we should consider what we view as impossible today as prohibitive to seeking out the technologies that will make it possible in the very near future.

WE CAN MAKE A SQUARE CIRCLE IF WE JUST DREAM HARD ENOUGH.


Automatically Appended Next Post:
PPS: you know what political system makes interstellar travel impossible? Capitalism. There is no conceivable profit motive for it, so you're depending on collectivization of resources (and the resources required are immense) for the state's goals at the expense of private industry. Which sounds an awful lot like communism...

Yodhrin wrote:And once again - if you don't do the basic, "blue sky" work now, you don't get the good stuff later.

Fun fact. Many many times in the past, humanity just goes and does stuff and figures out the theoretical side later on. Take flight for example (since it's recurring in this thread). The Wright brothers didn't have a clue about any of the theoretical forces involved in aerodynamics. They were bicycle salesmen by trade. It didn't stop them building a functional aeroplane through empirical testing and experimentation. There are plenty of other similar such stories in the history of science and technology. Marconi and wireless is another well known example.

I'm not making a broader point relevant to the discussion here. I just find it funny how much of human technology tends to come from some bloke putting one and five together to make eight; and then the rest of the world spends the next twenty years trying to figure out how he damn well did it.

 Peregrine wrote:

PPS: you know what political system makes interstellar travel impossible? Capitalism. There is no conceivable profit motive for it,

Hang on there just a minute. Want to lay claim to an entire solar system? Sounds profitable to me!

...but seriously, the capitalist system could create the wealth necessary to fund such an effort. It's not like the top capitalists of our days haven't spent huge sums on vanity projects. Part of the point of getting rich is so you can do crazy extravagant stuff with that money. It really depends how wealthy those space investors really get, and how concentrated that wealth is. Corporations owned by thousands or millions of investors won't bother. Corporations owned by a handful of super rich people? Maybe?

A Communist State doesn't really have any more incentive for interstellar travel than capitalists do. There's simply no short-term benefit in interstellar travel for anyone. There's not even a long-term benefit for anyone who stays behind because they're never going to see all of those resources again. If the motivation is mere exploration and research an unmanned mission could do the same things more efficiently and cheaply.

The only reasons for interstellar travel are as insurance against the extinction of the race or simply saying "why the feth not?"

 Ketara wrote:

Yodhrin wrote:And once again - if you don't do the basic, "blue sky" work now, you don't get the good stuff later.

Fun fact. Many many times in the past, humanity just goes and does stuff and figures out the theoretical side later on. Take flight for example (since it's recurring in this thread). The Wright brothers didn't have a clue about any of the theoretical forces involved in aerodynamics. They were bicycle salesmen by trade. It didn't stop them building a functional aeroplane through empirical testing and experimentation. There are plenty of other similar such stories in the history of science and technology. Marconi and wireless is another well known example.

I'm not making a broader point relevant to the discussion here. I just find it funny how much of human technology tends to come from some bloke putting one and five together to make eight; and then the rest of the world spends the next twenty years trying to figure out how he damn well did it.

I also find it funny how a lot of the stuff we use today also comes from failures and mistakes as well.

we may not have had super glue if some scientist wasn't trying to make cockpit windows. (relevant to this hobby)

 Luciferian wrote:
A Communist State doesn't really have any more incentive for interstellar travel than capitalists do. There's simply no short-term benefit in interstellar travel for anyone. There's not even a long-term benefit for anyone who stays behind because they're never going to see all of those resources again. If the motivation is mere exploration and research an unmanned mission could do the same things more efficiently and cheaply.

The only reasons for interstellar travel are as insurance against the extinction of the race or simply saying "why the feth not?"

Welllllllll dunno about the communist state but technology involved in the star race does have massive short and long term value. right nows its economically pooo to send stuff into space. that includes those satellites for your phones, gps, tv and all sorts of military and scientific stuff. first country to make a viable space elevator would make all the money back in a relatively reasonable time just hauling. long term ship tech has all sorts of technological implications from local space station sustainability to on earth sustainability for recycling and waste management which are all REALLY big industries (edit: also probably various technology involving equipment production like 3d printing and medical tech and knowledge). i dont think anyone would reasonably think we could achieve complete interstellar travel or even colonize mars but the slow steps in getting to it is very much worth while from a scientific and potentially financial position.

at least imho.

Some advances come from trial and error, some come from accidents, or inspired ideas, and some come from careful experiment design and theoretical study.

 Desubot wrote:


Welllllllll dunno about the communist state but technology involved in the star race does have massive short and long term value. right nows its economically pooo to send stuff into space. that includes those satellites for your phones, gps, tv and all sorts of military and scientific stuff. first country to make a viable space elevator would make all the money back in a relatively reasonable time just hauling. long term ship tech has all sorts of technological implications from local space station sustainability to on earth sustainability for recycling and waste management which are all REALLY big industries (edit: also probably various technology involving equipment production like 3d printing and medical tech and knowledge). i dont think anyone would reasonably think we could achieve complete interstellar travel or even colonize mars but the slow steps in getting to it is very much worth while from a scientific and potentially financial position.

at least imho.

Fair enough, those are good points. I was merely thinking about the act of interstellar travel itself, but the technology required would certainly be valuable in many other fields and applications.

 Peregrine wrote:

PPS: you know what political system makes interstellar travel impossible? Capitalism. There is no conceivable profit motive for it, so you're depending on collectivization of resources (and the resources required are immense) for the state's goals at the expense of private industry. Which sounds an awful lot like communism...

This thread is about Mars specifically, not vast interstellar travel. That chat is somewhat off topic. Either way, I addressed this point in my very first post - Musk understands that the Mars offer needs to be commercialised and is attempting to do so. There absolutely is profit motive for a presence on Mars. I can think of a number of corporations that would support a colonisation effort for advertising and positive altruistic promotion alone. The idea is to create a thriving economy in its own right, mining of raw materials is only one part of the puzzle.

 An Actual Englishman wrote:
There absolutely is profit motive for a presence on Mars.

{citation needed}

What exactly is that profit motive? Selling billion-dollar trips to bored rich people?

mining of raw materials is only one part of the puzzle.

Mining raw materials is not one part of the puzzle, it's zero pieces of the puzzle. There is no way to make it viable, period.


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 Luciferian wrote:
A Communist State doesn't really have any more incentive for interstellar travel than capitalists do.

No, it doesn't, but it at least starts from the premise of collectivization of industry and a state-controlled economy. In a capitalist state of NASA wants to build an interstellar (or even just interplanetary) spacecraft they have to convince the voters to fund it, convince private industry to accept contracts to do the job, etc. If a communist state wants to build that spacecraft they can simply declare that it is the new goal of the state and everything required can be directed to the project. There is no private industry to object and say "that's not an efficient use of my factory, I want more profit".

 An Actual Englishman wrote:


(...) I can think of a number of corporations that would support a colonisation effort for advertising and positive altruistic promotion alone(...)

Oh god, the "Mcdonalds" Mars colony here we go!

A functional space lift could be a good first start to space bound activities? Carbon nanotubes could theoretically handle the load but would find it difficult and dangerous currently. Looking at the history of materials development however, it isn't inconceivable that another substance could be along in the next few decades which would render the space lift a workable engineering feat. Given the amount of satellites and items we put into orbit already, there'd be a clear economic incentive to get one up and running; not to mention the military ramifications.

Once you've got a space lift, you can build a large space station on the other end. Once you've a large space station, you can build futher craft designed to move around up there unburdened by the insane needs for fuel and huge engines and re-entry. Much submarine style technology becomes transferrable to spaceship construction; be it drones or manned. At that point, the economic costs of mining asteroids for exceptionally rare materials goes down to bearable levels; especially given their finite nature and geopolitical concerns about over-reliance on certain third world nations effectively owned by China.

If you told me that that would be the state of affairs in fifty years time; I don't think you'd be making an unreasonable jump in assumptions. From there? Who knows. I doubt we'd see a colony before the above, but once we've got a means of porting materials to and from space without bothering with the gravity well challenge, the sky is very literally the limit.

 An Actual Englishman wrote:

 Peregrine wrote:

PPS: you know what political system makes interstellar travel impossible? Capitalism. There is no conceivable profit motive for it, so you're depending on collectivization of resources (and the resources required are immense) for the state's goals at the expense of private industry. Which sounds an awful lot like communism...

This thread is about Mars specifically, not vast interstellar travel. That chat is somewhat off topic. Either way, I addressed this point in my very first post - Musk understands that the Mars offer needs to be commercialised and is attempting to do so. There absolutely is profit motive for a presence on Mars. I can think of a number of corporations that would support a colonisation effort for advertising and positive altruistic promotion alone. The idea is to create a thriving economy in its own right, mining of raw materials is only one part of the puzzle.

I won't trust Musk on Mars to create a thriving economy until capitlaism has managed to create one on Earth. It's not looking good ATM unless you're in the top few per cent, in which case it's looking groovy.

dyndraig wrote:

 An Actual Englishman wrote:


(...) I can think of a number of corporations that would support a colonisation effort for advertising and positive altruistic promotion alone(...)

Oh god, the "Mcdonalds" Mars colony here we go!

Lol indeed. Or 'Mars Mars colony'. Coca Cola™ Colony etc.

 Kilkrazy wrote:
I won't trust Musk on Mars to create a thriving economy until capitlaism has managed to create one on Earth. It's not looking good ATM unless you're in the top few per cent, in which case it's looking groovy.

A thriving economy doesn't need to have wealth parity for all parties. I mean a thriving economy in the sense that businesses will see profit in and want to get involved with a Mars expedition. As the context of the discussion at hand (Mars/Interstellar travel will never happen because of capitalism).

 An Actual Englishman wrote:
I mean a thriving economy in the sense that businesses will see profit in and want to get involved with a Mars expedition.

Depends on who is funding it. Businesses funding their own Mars expedition with a goal of making it profitable? Hell no, not going to happen. The government(s) deciding to go to Mars and businesses eagerly accepting that money to provide goods and services for it at the usual inflated government contract rate? Of course. But NASA handing out blank checks at taxpayer expense is hardly the same as Mars being profitable.


Automatically Appended Next Post:

 Ketara wrote:
Carbon nanotubes could theoretically handle the load

Key point: theoretically. We're a long, long way off from getting materials that can handle the load and can be created in sufficient quantities to build a space elevator. And then even if you can build one it's still an incredibly expensive and difficult project. 50 years is wildly optimistic, if it's even possible at all.

 An Actual Englishman wrote:

dyndraig wrote:

 An Actual Englishman wrote:


(...) I can think of a number of corporations that would support a colonisation effort for advertising and positive altruistic promotion alone(...)

Oh god, the "Mcdonalds" Mars colony here we go!

Lol indeed. Or 'Mars Mars colony'. Coca Cola™ Colony etc.

 Kilkrazy wrote:
I won't trust Musk on Mars to create a thriving economy until capitlaism has managed to create one on Earth. It's not looking good ATM unless you're in the top few per cent, in which case it's looking groovy.

A thriving economy doesn't need to have wealth parity for all parties. I mean a thriving economy in the sense that businesses will see profit in and want to get involved with a Mars expedition. As the context of the discussion at hand (Mars/Interstellar travel will never happen because of capitalism).

I didn't say it needs wealth parity for all parties.

It does, however, need to "work" for a majority of the population in the sense of delivering improving living standards to the bottom rather than vast wealth to the top and static or lowering standards at the bottom. At the moment, the world's economy doesn't work in this sense.

If you've been following financial news for the past 40 years you will know that the world has lurched from business drama to economic crisis on a fairly regular cycle, and it's getting worse.

Dreadwinter wrote:This has been pretty enjoyable.

Good to know that Humans never thought that flight was impossible for them. Hell, cavemen were probably in laying down the groundwork for the first engine.

"All we need is more power." - Actual Quote from Cave Painting

Willfully missing what was being argued, but ho hum. That said, we do have some solid ideas about how people in the deep past viewed potential technological development. Adrienne Mayor, a classicist at Stanford, has just published Gods and Robots. Myths, Machines, and Ancient Dreams of Technology. No idea if it's any good, but I thought it might be of interest to some.

Luciferian wrote:That being said, it would only take a few decades to travel quite a ways across the galaxy using current propulsion technologies

Woah woah woah. How far is 'quite a ways'? Let's be immensely generous and suggest by 'quite a ways across the galaxy' you only mean 1% of the diameter of the galaxy. That'd take more than a 1000 years moving at light speed. Using current propulsion technologies? Well, someone who's not in the humanities can do the maths. There'll be a lot of numbers.

 Peregrine wrote:
Key point: theoretically. We're a long, long way off from getting materials that can handle the load and can be created in sufficient quantities to build a space elevator. And then even if you can build one it's still an incredibly expensive and difficult project. 50 years is wildly optimistic, if it's even possible at all.

Yet again I find it funny that you think we can manage to get completely autonomous robots flinging around the solar system doing every task imaginable when we can barely get them to handle complex tasks on EARTH without being babysat, yet you think the industries responsible for solid materials can't advance enough to make a carbon fiber able to fill those needs.

 Just Tony wrote:

 Peregrine wrote:
Key point: theoretically. We're a long, long way off from getting materials that can handle the load and can be created in sufficient quantities to build a space elevator. And then even if you can build one it's still an incredibly expensive and difficult project. 50 years is wildly optimistic, if it's even possible at all.

Yet again I find it funny that you think we can manage to get completely autonomous robots flinging around the solar system doing every task imaginable when we can barely get them to handle complex tasks on EARTH without being babysat, yet you think the industries responsible for solid materials can't advance enough to make a carbon fiber able to fill those needs.

Isn't the primary problem with getting autonomous robots to function on earth precisely the fact they're on earth where they have to interact with other autonomous things and environmental stresses? You don't have to interact with much in space. It's really big and really empty. Even in relatively busy places like Earth's orbit.

We've got a number of semi-autonomous robots doing quite diffficult things like exploring Mars and the asteroids right now.

They have to be capable of lot of independent work because the control time is too long to allow real-time guidance.

Self-guiding cars are about to hit the big time on Earth.

 Ketara wrote:

Yodhrin wrote:And once again - if you don't do the basic, "blue sky" work now, you don't get the good stuff later.

Fun fact. Many many times in the past, humanity just goes and does stuff and figures out the theoretical side later on. Take flight for example (since it's recurring in this thread). The Wright brothers didn't have a clue about any of the theoretical forces involved in aerodynamics. They were bicycle salesmen by trade. It didn't stop them building a functional aeroplane through empirical testing and experimentation. There are plenty of other similar such stories in the history of science and technology. Marconi and wireless is another well known example.

I'm not making a broader point relevant to the discussion here. I just find it funny how much of human technology tends to come from some bloke putting one and five together to make eight; and then the rest of the world spends the next twenty years trying to figure out how he damn well did it.

Engineering is practical [stage] magic. Science is sitting down and working out the trick afterwards.

 Peregrine wrote:

Key point: theoretically.

Well, yeah. That's why I said it. If I wasn't aware of the problems involved (the fact it doesn't work if a single atom is displaced, and production difficulties), I'd have just said it was 'possible'.

We're a long, long way off from getting materials that can handle the load and can be created in sufficient quantities to build a space elevator.

This however, is also hypothetical. It's pure speculation. There could be a breakthrough in a lab tomorrow which comes up with a revolutionary new building material which isn't really that expensive or difficult to produce. People thought airships were impractical to build with existing materials; then somebody went and synthesized duralumin. Looking back at the last fifty years of developments in metallurgy and materials composition; we've advanced far further in the intervening time period than compared to jumping from carbon nanotubes to something maybe 10% stronger (we really don't need much more advancement to get workable materials for a space elevator).

And then even if you can build one it's still an incredibly expensive and difficult project. 50 years is wildly optimistic, if it's even possible at all

I'm not entirely sure how one could attempt to cost a fictitious not-existing construction material; let alone make sweeping statements about the construction times involved on the basis of that imagined cost.

If a material becomes available, it doesn't even necessarily have to be cheap. It just needs to be more cost effective to build the elevator than the price of a few hundred odd rocket launches which would otherwise be required for launching satellites and the like in the immediately subsequent years. If it can be cheaper than those rockets, it'll pay for itself. And if it can't, people will doubtless spend considerable amounts of time/years working down the cost price until it is; because the need to put things in space ain't going nowhere.


I don't think anything will happen on a 'space exploration' front until that space elevator is in place though, be it in twenty five or fifty, or a hundred years time. It's just not cost-effective, and there's nothing we need badly enough. Once there's an energy-efficient way of hauling stuff up to orbit and back, that barrier will vanish, but until then? We won't see more than the odd satellite launch and scientific mission.

 Kilkrazy wrote:
I didn't say it needs wealth parity for all parties.

It does, however, need to "work" for a majority of the population in the sense of delivering improving living standards to the bottom rather than vast wealth to the top and static or lowering standards at the bottom. At the moment, the world's economy doesn't work in this sense.

If you've been following financial news for the past 40 years you will know that the world has lurched from business drama to economic crisis on a fairly regular cycle, and it's getting worse.

You implied wealth parity for all parties. Either way you’re still misinterpreting my point. I don’t think I can make it clearer than the last post so I’ll leave it.

Regarding your point and what it needs to “work” (I’m not sure why or how we’ve seemingly slipped into discussing the virtues and flaws of capitalist society in a thread around Mars, mind) - I think for many it would be a massive improvement in their living living standards. We live in a world where many people have no access to basic things like clean water, relative safety, shelter or employment etc. I would expect a Mars colony to offer some of these as a minimum.

The “problem” then becomes how we encourage financiers and other wealthy types to commit and the morality of creating what would be in effect a voluntary prison for the most vulnerable/least wealthy.

Even if it wouldn't be profitable to ship stuff back to Earth proper, building colonies on Mars, colony space stations, etc... will all need resources easily found in the Solar system. Which would make it profitable to mine them.

 Grey Templar wrote:
Even if it wouldn't be profitable to ship stuff back to Earth proper, building colonies on Mars, colony space stations, etc... will all need resources easily found in the Solar system. Which would make it profitable to mine them.

I dunno. would a colony situated so far away that shipping stuff back and forth wouldn't matter really need an economy to even care about profits?