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 Peregrine wrote:
Getting to 0.9c is science fiction, not reality.

Not really. It is beyond our ability now. But it is physically possible.

 Grey Templar wrote:

 Peregrine wrote:
Getting to 0.9c is science fiction, not reality.

Not really. It is beyond our ability now. But it is physically possible.

The energy requirements are pretty staggering. IIRC people who have done the math think 0.1C could be done with fusion power plants. Remember you've got to bring your own reaction mass for decades or centuries of the journey. The energy and reaction mass requirements won't change without other factors, like using giant lasers to push ships up to speed.

 Grey Templar wrote:

 Peregrine wrote:
Getting to 0.9c is science fiction, not reality.

Not really. It is beyond our ability now. But it is physically possible.

It is physically possible, but it is still science fiction. The energy and reaction mass requirements to get moving that fast are way beyond any foreseeable ability to build.

 Peregrine wrote:

 Grey Templar wrote:

 Peregrine wrote:
Getting to 0.9c is science fiction, not reality.

Not really. It is beyond our ability now. But it is physically possible.

It is physically possible, but it is still science fiction. The energy and reaction mass requirements to get moving that fast are way beyond any foreseeable ability to build.

At one point, that argument applied to flight too.

NASA has figured out a theoretical method of bending space like Star Trek Warp Drives do, and the energy requirements are well within what Fusion power plants could provide. If they ever figure out a practical way to bend space our current engine tech could give us FTL/Near-FTL.

It does fall under the realm of "cheating" the laws of physics of course.

Rosebuddy wrote:

 Vulcan wrote:

 Yodhrin wrote:
All that said, if we decide to allow corporations to go off and stripmine the solar system(and we bloody well shouldn't)...

Out of curiousity... why not? Would you rather they stripmine the earth, with all the ecological damage that entails? I would think it to be better to stripmine lifeless bodies rather than wreck the one body with a functioning ecosystem we can survive in...

So, okay. corporations are stripmining the planet we live on and are going to kill us all. That's what we're going with here. Why would we give them more to stripmine instead of stopping them from killing us all?






People can imagine the most fanciful leaps of technology to put people on Mars but can't imagine implementing already known systems to solve our current problems. Space discussion is just so myopic.

Because a lot of the problems on earth stem directly from resource shortage, and no amount of fanciful leaps in technology (short of Star Trek replicators) will ever solve that. But go out in space and there's a LOT more resources to play with.

And you call me myopic...

 Grey Templar wrote:

 Peregrine wrote:

 Grey Templar wrote:

 Peregrine wrote:
Getting to 0.9c is science fiction, not reality.

Not really. It is beyond our ability now. But it is physically possible.

It is physically possible, but it is still science fiction. The energy and reaction mass requirements to get moving that fast are way beyond any foreseeable ability to build.

At one point, that argument applied to flight too.

No. It did not. Or rather, we have no evidence that anyone ever thought this. On the other hand, as tackled on the previous page, we know for a fact that humans have known things could fly for as long as there have been humans..

Science fiction is not always synonymous with 'impossible'. It's often 'requires as yet non-existent technology'. Sure maybe in the neolithic folks saw birds and thought human flight utterly farcical, but we didn't achieve it for several thousand years after that, and 'millennia in the future' seems pretty close to 'science fixtion' to me.

 Grey Templar wrote:
At one point, that argument applied to flight too.

No, it really didn't. Sure, there was a point where people looked at flight and said "this requires too much power, it will never happen" but that's primarily out of a lack of understanding of aerodynamics and power and such preventing them from knowing how much power is required. It was just blind guessing and looking at birds. With accelerating to 0.9c we aren't blind guessing, we're looking at the energy and reaction mass requirements and knowing exactly how difficult the problem is and how far we are from getting anywhere near that fast. There is no "oh, now we get it" moment to be had. You simply require orders of magnitude more energy and reaction mass than we are capable of providing. So yes, it's theoretically possible that someday we'll develop an engine efficient enough to do it, but right now it's firmly in the realm of speculation and science fiction.

NASA has figured out a theoretical method of bending space like Star Trek Warp Drives do, and the energy requirements are well within what Fusion power plants could provide. If they ever figure out a practical way to bend space our current engine tech could give us FTL/Near-FTL.

It does fall under the realm of "cheating" the laws of physics of course.

When the premise of the idea is "we figure out a practical way to bend space" you have definitely moved into science fiction.

nfe wrote:

No. It did not. Or rather, we have no evidence that anyone ever thought this. On the other hand, as tackled on the previous page, we know for a fact that humans have known things could fly for as long as there have been humans.

We know things can travel through space. We have evidence that at least some people thought this as there are countless literary works exclaiming such.

 Peregrine wrote:

 Grey Templar wrote:
At one point, that argument applied to flight too.

No, it really didn't. Sure, there was a point where people looked at flight and said "this requires too much power, it will never happen" but that's primarily out of a lack of understanding of aerodynamics and power and such preventing them from knowing how much power is required.

Kinda what you're doing here then?

The information you have about this is limited at best.

There are a umber of people in this discussion stating what is ultimately their opinion as fact. That's fine but it doesn't change it from being you opinion.

At one point the human race did not have the understanding or the capabilities to make human flight possible. At one point the human race did not have the means or capabilities to allow people from across the world to discuss little models at their leisure. There would have been Peregrines or nfes back then stating that these things would never happen.

The facts are that its very, very unlikely that anyone here has any real authority on this discussion so it comes down to a matter of belief. I'm choosing to believe that it is possible for the human race to one day colonise the stars. If Mr Hawking believed it possible, a man much more intelligent than everyone here I'd wager, I think there is some merit to this belief.

 An Actual Englishman wrote:
Kinda what you're doing here then?

No. Again, there is a difference between "we don't know how flying works, is it even possible" and "we know exactly how acceleration to 0.9c works, how much energy and reaction mass is required, and how immensely far beyond our foreseeable ability those problems are".

The information you have about this is limited at best.

There are a umber of people in this discussion stating what is ultimately their opinion as fact. That's fine but it doesn't change it from being you opinion.

No, I am stating facts. Not opinions. This is not a subject you get to have opinions about, the power and reaction mass requirements are not things that are up for debate. The fact that you think otherwise is just demonstrating your very limited knowledge of the subject.

The facts are that its very, very unlikely that anyone here has any real authority on this discussion so it comes down to a matter of belief.

You're much like the cheated-on spouse declaring that their partner is 100% faithful: believing a feel-good lie because you don't like the uncomfortable truth, and making up whatever rationalizations are required to keep believing.

 Peregrine wrote:

No, I am stating facts. Not opinions. This is not a subject you get to have opinions about, the power and reaction mass requirements are not things that are up for debate. The fact that you think otherwise is just demonstrating your very limited knowledge of the subject.

"You have definitely moved into science fiction." This is an opinion.

"Way beyond any forceeable way to build" This is an opinion. Unless you know what the future holds?

"Getting to 0.9c is science fiction, not reality." This is again an opinion.

You realise there could be a scientific breakthrough today that renders your pessimism around this completely wrong? You are not educated enough in this topic to speak with any credibility (hence it's your opinion). Or if you believe you are - prove it.

 An Actual Englishman wrote:
"You have definitely moved into science fiction." This is an opinion.

No, it is fact. A spacecraft capable of accelerating to 0.9c is immensely beyond our ability to build, and anything involving one is pure speculation at best. IOW, the very definition of science fiction.

"Way beyond any forceeable way to build" This is an opinion. Unless you know what the future holds?

There's a reason the word "foreseeable" is in that sentence. Based on all current knowledge and reasonable extrapolation of current technology a spacecraft capable of accelerating to 0.9c is far, far in the future at best and we have no idea how to get there.

You realise there could be a scientific breakthrough today that renders your pessimism around this completely wrong?

And I could win every lottery for the next year. I'm not betting on either of these happening, and there's no point in discussing wild speculation without a single scrap of evidence to support it.

You are not educated enough in this topic to speak with any credibility (hence it's your opinion). Or if you believe you are - prove it.

You first.

 Peregrine wrote:

There's a reason the word "foreseeable" is in that sentence. Based on all current knowledge and reasonable extrapolation of current technology a spacecraft capable of accelerating to 0.9c is far, far in the future at best and we have no idea how to get there.

You know this do you? You know the total of ‘all current knowledge” relating to the question of achieving sub light speed or FTL spacecraft? You don’t?! Because you’re a random guy on a forum about toy soldiers and not a super computer/genius level intellect working for NASA.

This is why I said this and is why it holds true;

You are not educated enough in this topic to speak with any credibility (hence it's your opinion). Or if you believe you are - prove it.

I don’t need to prove my credibility, I have stated that this is my opinion based on reading around the topic from sources created by intellects much greater than mine. That’s the difference between us - I’m not shouting my beliefs as if they are facts.

 An Actual Englishman wrote:
You know this do you? You know the total of ‘all current knowledge” relating to the question of achieving sub light speed or FTL spacecraft? You don’t?! Because you’re a random guy on a forum about toy soldiers and not a super computer/genius level intellect working for NASA.

I know enough about current knowledge to know that the energy and reaction mass requirements for accelerating to 0.9c are orders of magnitude beyond anything we can do, and orders of magnitude beyond even theoretical foreseeable-future projects which have been proposed. I know that the highly ambitious "maybe within our lifetimes, if we had a massive budget and everything worked right to turn this tentative theory into a working prototype" sort of ideas are still well short of 0.9c and not even attempting to set that as a goal. And I also know that ridiculous stereotypes of "genius level intellect" are much less of a realistic portrayal of science than well-run teams of competent engineers, and that it doesn't take "genius level intellect" to be a competent engineer.

I’m not shouting my beliefs as if they are facts.

Yes you are. Your opinion is "you can't know", and you're stating it as fact complete with confidently declaring that I have no significant knowledge of the subject. Now either follow your own principle that not being a "super computer/genius level intellect working for NASA" means you don't know enough to make any statements and stop commenting, or post your credentials justifying that your opinion has value under your own standards.

Eh, such a leap as interstellar travel can't really be predicted, nor should it be counted on. Work with what we know of for 'in our lifetime' projections. It'll take 30 or 40 years for a new technology to be fully realized.

I love these threads because what we are capable of is so much more than we were. Ion drives exist, and are being made more powerful in preparation for moving humans to Mars. They're already working on satellites above us as we speak.

We've made solar sail drives as well, and have had success with them- though they have not yet been adopted for practical purposes.

These aren't going to get us out of the solar system, but they are allowing much greater range for our spacecraft, increasing the types of missions we can do. Asteroid mining and interplanetary travel are plenty exciting for my lifetime!

It's certainly possible to calculate the requirements for accelerating a spacecraft to 0.9c using ion drives, because we are already flying spacecraft with ion drives and have actual engineering data on energy and propellant consumption and efficiency.

I don't know if that calculation produces a workable result.

The suggestions I've seen for what's required for a self-sufficient colony on an uninhabitable planet or in a space station - assuming that it's technically possible to design the sort of machinery required to build and maintain such a structure indifeinitely - require a society that would make societies like the Imperium of Man, the Tau and Margaret Atwood's Gilead look socially progressive paragons of liberty by comparison. I don't think we've got the mindset for it as we are now.

Yeah lightspeed travel at this point is essentially science fiction simply due to the fact that we would need so many new technologies to make it viable. Even if we invent an engine capable of such speeds, we need a power source to keep it running and a material to resist space debris that would rip anything we have made so far to shreds.

By the time we could travel at those speeds, we would also have solved the world energy crisis, built a space elevator, and colonized a planet. I'm not saying it wouldn't be awesome, just that it is many hundreds of years away...

 AndrewGPaul wrote:
The suggestions I've seen for what's required for a self-sufficient colony on an uninhabitable planet or in a space station - assuming that it's technically possible to design the sort of machinery required to build and maintain such a structure indefinitely - require a society that would make societies like the Imperium of Man, the Tau and Margaret Atwood's Gilead look socially progressive paragons of liberty by comparison. I don't think we've got the mindset for it as we are now.

That's why we have madmen like Musk to do all the hard work for us! Colonies are going to grow not due to a united human race but due to companies wanting to make a profit and there are no shortage of them right now.

Yeah, but a free-marketer of a libertarian bent is … pretty much the opposite of what you want as the population of an isolated colony.

 Vulcan wrote:

Because a lot of the problems on earth stem directly from resource shortage, and no amount of fanciful leaps in technology (short of Star Trek replicators) will ever solve that. But go out in space and there's a LOT more resources to play with.

And you call me myopic...

Any resource shortage on this planet is mainly because we have a system of distribution that tips resources off a cliff and into a big smelly hole. We don't actually need to have multiple new models of car, refrigerator and phone every year and could easily do without. But no, it's easier to imagine magical Space Technology that will forever feed this madness than it is to imagine the end of capitalism.

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

 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

Cavemen drew manuals for killing wooly mammoths with sharpened sticks! They were not a cautious people.

Egyptians, Greeks, Romans, the Jewish people, Indians, First Nations people all have flight myths, many dating back to thousands of years BC. I see no reason to assume cave men didn't dream of spreading their smelly, slope browed wings and flying.


https://www.bibliotecapleyades.net/esp_aviones_precolom02.htm

 John Prins wrote:

 Iron_Captain wrote:

If we are at the point where we can feasibly build a fully functioning settlement in space then we are also at the point where we can reinforce Mars' magnetic field and atmosphere to the point that it becomes a pleasant place for humans to live.

Well, not exactly. Giving Mars a magnetic shield is simple, but not easy. Basically you need a copper coil that can surround the planet, placed in orbit in front of the planet, to generate a magnetic field. It's a huge engineering project you'd probably need a space colony to build in the first place.

Wheel type space colonies are within our engineering capacity now and expandable (add more wheels). For anything space related, orbital manufacturing and off-world harvesting is going to be necessary. That should be the goal - once we have that, then the only limit is our engineering capacity.

A powerful magnet placed at Mars' L1 point will do. This would create a magnetic shield around Mars to protect it. We already have magnets that are far more powerful than what would be needed to create such a shield. The only issue is of course getting that magnet into space. Again, it is possible to do with current technology already, but the costs are high and no space program really has the funds or the priorities to do it. So it is a lot less of an issue than getting an entire space colony into space. Even a small station like the ISS is already a huge undertaking. Let alone a semi-permanent colony or orbital manufacturing. That is pretty far beyond our technological capabilities. Shooting a junkyard magnet into space is not.

Rosebuddy wrote:

 Vulcan wrote:

Because a lot of the problems on earth stem directly from resource shortage, and no amount of fanciful leaps in technology (short of Star Trek replicators) will ever solve that. But go out in space and there's a LOT more resources to play with.

And you call me myopic...

Any resource shortage on this planet is mainly because we have a system of distribution that tips resources off a cliff and into a big smelly hole. We don't actually need to have multiple new models of car, refrigerator and phone every year and could easily do without. But no, it's easier to imagine magical Space Technology that will forever feed this madness than it is to imagine the end of capitalism.

Don't you mean REdistribution? That's basically what your bend is about, correct?


Anybody ever own a Commodore 64? I did. You remember the max storage capacity on a floppy disk? THAT was 30 years ago. Not only has storage medium changed SEVERAL times in that timeframe, but we also are to the point that we can make ridiculous memory for next to nothing. How is it that nobody thinks that OTHER technologies can be progressed the same way?

Rosebuddy wrote:

 Vulcan wrote:

Because a lot of the problems on earth stem directly from resource shortage, and no amount of fanciful leaps in technology (short of Star Trek replicators) will ever solve that. But go out in space and there's a LOT more resources to play with.

And you call me myopic...

Any resource shortage on this planet is mainly because we have a system of distribution that tips resources off a cliff and into a big smelly hole. We don't actually need to have multiple new models of car, refrigerator and phone every year and could easily do without. But no, it's easier to imagine magical Space Technology that will forever feed this madness than it is to imagine the end of capitalism.

Actually I imagine the end of capitalism is far closer than many think. For example, RIGHT NOW pretty much every management position in the world can be dispensed with. All it would take is the software to gather and collate data from the working locations and report it to a central location (already available), and the communication technology for the central location to communicate back with the working locations (also already available). There goes a few million white-collar jobs...

Let's face it. Aside from creative processes and raw scientific research, there's precious little human work that we can't do right now with computers, robots, and modern communication. Maybe not economically just yet, but that's just a matter of time.

After replacing human labor for most everything becomes economically viable, there goes mass employment. Without mass employment, under capitalism there is no mass consumption, therefore no incentive for mass production. And capitalism goes out the window, replaced either by some form of socialism/communism, or economic feudalism.

At any rate... I have a certain respect for Elan Musk. At least he has a vision for his businesses beyond 'GIMME!'.

 Iron_Captain wrote:

A powerful magnet placed at Mars' L1 point will do. This would create a magnetic shield around Mars to protect it. We already have magnets that are far more powerful than what would be needed to create such a shield. The only issue is of course getting that magnet into space. Again, it is possible to do with current technology already, but the costs are high and no space program really has the funds or the priorities to do it. So it is a lot less of an issue than getting an entire space colony into space. Even a small station like the ISS is already a huge undertaking. Let alone a semi-permanent colony or orbital manufacturing. That is pretty far beyond our technological capabilities. Shooting a junkyard magnet into space is not.

Pretty much exactly what I'm describing (in my case, it's a solar powered electromagnet), and yes, Mars-Sun L1 point is where you'd put it. https://space.stackexchange.com/questions/14352/place-a-satellite-at-sun-mars-l1-to-shield-mars-from-sun-radiation has the simplest explanation I've seen. Making a magnet powerful enough isn't the hard part, it's making it large enough.

Note this doesn't protect Mars from background galactic radiation like a proper magnetosphere would, but you'd need a much weaker field around Mars to handle just that.

 Gitzbitah wrote:

 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

Cavemen drew manuals for killing wooly mammoths with sharpened sticks! They were not a cautious people.

Egyptians, Greeks, Romans, the Jewish people, Indians, First Nations people all have flight myths, many dating back to thousands of years BC. I see no reason to assume cave men didn't dream of spreading their smelly, slope browed wings and flying.


https://www.bibliotecapleyades.net/esp_aviones_precolom02.htm

Dreaming of flying and making stories of flying are different than understanding complex engineering issues regarding how flying actually works.

Wait, hold on, how did we go from "Mars is a necessary first step on a journey that will eventually involve leaving the solar system" to "Leaving the solar system is pure fiction! That's ridiculous! You're ridiculous!"?

I'm fairly certain nobody's arguing we colonise Mars and then immediately start building the USS fething Enterprise, yeah.

And once again - if you don't do the basic, "blue sky" work now, you don't get the good stuff later. Theoretical physics first, microchips later. Mars & asteroid colonies first, interstellar travel(most likely generational IMO) and terraforming later. Even that line of thinking discounts all the benefits from discoveries that will inevitably accrue just as a result of the process - and none of this "we could just do targeted research" guff, since even ignoring the prior point that was made about sometimes needing big, emotive, "humanity is awesome yeah!" stuff to motivate the public to back science spending if you want money to spend on science at all, a lot of discoveries aren't intentional at all, let alone the result of someone setting out specifically from the beginning to discover them.

 Just Tony wrote:
How is it that nobody thinks that OTHER technologies can be progressed the same way?

Because we actually understand the mass and energy requirements even under the most generous possible assumptions? No amount of clever technology is going to change the fact that it takes an obscene amount of energy and reaction mass to accelerate to speeds useful for interstellar travel. No amount of clever technology is going to change the fact that moving minerals out of a planetary gravity well is going to be prohibitively expensive compared to getting them from asteroids or on the planet we already live on. The only thing technological progression is going to do is continue to make robots more and more effective, continuing to reduce any possible argument for wasting payload capacity on humans.

Also, I love the "BUT WHAT ABOUT AIRPLANES" arguments from people who obviously don't understand much about science or engineering and how the process works.


Automatically Appended Next Post:

 Yodhrin wrote:
a lot of discoveries aren't intentional at all, let alone the result of someone setting out specifically from the beginning to discover them.

That's a nonsense argument. If discovery isn't intentional or predictable* then ANY science/engineering project could possibly have them as a side effect. Building space colonies isn't any more likely to produce desired side effects than developing a space program to etch a giant dick into the moon. Or, more seriously, than having a targeted research program aimed at one of your known goals. The idea that we should spend vast amounts of money on something with negligible, if any, direct return in the desperate hope that we accidentally manage to do something useful with it is utter lunacy.

*If it is predictable then you can do targeted research, making your argument invalid.

"Robots making everything while we sit on our asses getting free money and Doritos while we play our PS14's, screw space travel!" - Peregrine.


That about the gist of it? When it comes down to it, we've already created SEVERAL different methods of lifting and hauling loads greater than what we thought we could lift. JUST as other forms of memory have been invented and perfected, other forms of propulsion will be invented and perfected. The problem with you is that you can't see past your desire to live off of other people's money long enough to see the benefit to the species as a whole. Not to mention the fact that, as was already pointed out once, colonization means the survival of NOT JUST OUR SPECIES but every transplantable species on the planet. Create a colony on Mars, and NOBODY will be hunting Bengal Tigers up there, for instance.

I've been doing some sums on ion propulsion.

NASA's Deep Space 1 probe, considered a very successful design from the late 1990s, spent 3,888 hours and 22 Kg of propellant to boost the 450Kg spacecraft up to 1.3 km per second.

This is a respectable velocity, but it's still only 1/230,000 of the speed of light.

The next generation of ion drives are twice as efficient, but even so, you can see the vast problem of interstellar travel.