Quote from: Supergravity on 02/21/2014 02:08 amQuote from: Cinder on 02/21/2014 12:56 amYou said "never". Not merely "not in foreseeable future". We're not nearly capable yet of foreseeing "forever". It's not a meaningless distinction.I realize I said never. That's simply because we pretty much have cracked all of the puzzles of fundamental physics, and any new "breakthroughs" will not at all yield any new insights that could lead to potentially revolutionary technologies. Unless everything we know about physics so far is wrong (a complete fantasy), then it's not at all unreasonable to conclude humans will never leave the solar system. Scientists and engineers at a propulsion conference not too long ago also came to the same conclusion.Their and your working assumption is that spaceflight and underlying physics/engineering operate in vacuum.
Quote from: Cinder on 02/21/2014 12:56 amYou said "never". Not merely "not in foreseeable future". We're not nearly capable yet of foreseeing "forever". It's not a meaningless distinction.I realize I said never. That's simply because we pretty much have cracked all of the puzzles of fundamental physics, and any new "breakthroughs" will not at all yield any new insights that could lead to potentially revolutionary technologies. Unless everything we know about physics so far is wrong (a complete fantasy), then it's not at all unreasonable to conclude humans will never leave the solar system. Scientists and engineers at a propulsion conference not too long ago also came to the same conclusion.
You said "never". Not merely "not in foreseeable future". We're not nearly capable yet of foreseeing "forever". It's not a meaningless distinction.
The few gaping holes such as gravity (which has, in fact, already been established in the medium-energy limit) will never give way to anything practical, especially something that can be used for propulsion. Even our best accelerators in the distant future may turn up nothing when it comes to quantum gravity effects, so it would be laughable to even speculate of a propulsion mechanism that takes advantage of such practically non-existent effects.
The problem is that there is no guarantee whatsoever that better propulsion schemes are feasible or even actually exist, so putting money into it is quite a wager and would not be wise.
Advanced propulsion is one thing, but it will be at least a century before we will be thinking about other stars. Why are we not right now expanding out into our solar system, putting bases on asteroids and so on? You don't need advanced propulsion for that, just things like the ability to store fuel in tanks for a year or more and not have it all leak away, ie propellant depots, and life support that you can trust for missions that take you a year or more from earth.
Quote from: KelvinZeroAdvanced propulsion is one thing, but it will be at least a century before we will be thinking about other stars. Why are we not right now expanding out into our solar system, putting bases on asteroids and so on? You don't need advanced propulsion for that, just things like the ability to store fuel in tanks for a year or more and not have it all leak away, ie propellant depots, and life support that you can trust for missions that take you a year or more from earth.I disagree. I think that none of the currently available propulsion systems is advanced enough to facilitate a larger scale exploration (and maybe colonization) of the solar system. Current systems would allow for single "event" missions (like Apollo), but even going back to the moon is too expensive and too complicated with todays technology to allow for a more permanent presence of humans. Mars is even worse, which is why I think that anybody who wants to do mars (exploration or even worse colonization like Musk), is solving the problem from the wrong end. We first absolutely need to make transport to LEO routine and extremely cheap. Even SpaceX is not going to lower the cost enough to achieve that (don't get me wrong, I love the guys and applaud their effort). This is why I wished SpaceX was investing more into propulsion research. Someone like Musk could easily finance a Propulsion Xprize of sorts.VASIMIR, like all electric propulsion systems suffers from too little power. If we could solve the power supply problem, then a lot of high Isp propulsion systems could become a lot more useful. This is something else that such a prize could focus on (which some very earthly applications as well). I wished NASA would make advancing the state of the art of space flight components a higher priority, a NIAC on steroids if you want.
And let me point out, for the "science has answered all the major Physics questions" types, there is still no settled theory that explains the nature or behavior of inertia. Like gravity prior to Newton, it still seen as something intrinsic...
On another note, it also seems that a few countries failed to get probes to arrive on the moon as well as Mars in the last century.
This opens a can of worms that has been a big issue on this forum, and has derailed many threads. You are asking about why NASA is not putting a really big effort into advanced propulsion, but a bigger question is why NASA is not putting the effort it could into ANY technology development that would change the nature of HSF.
Advanced propulsion is one thing, but it will be at least a century before we will be thinking about other stars. Why are we not right now expanding out into our solar system, putting bases on asteroids and so on?
You don't need advanced propulsion for that, just things like the ability to store fuel in tanks for a year or more and not have it all leak away, ie propellant depots, and life support that you can trust for missions that take you a year or more from earth.
Another obvious technology to advance is SEP (solar electric propulsion) for HSF, which could let us engage in much larger scale projects beyond earth orbit more cheaply. Probably the most important technology is ISRU, without which going anywhere has little point.
If you understand why NASA is not being allowed to put significant development into even solving these BASIC problems, you will have a good clue why even less money is making it to truly advanced propulsion. Explore all the other threads and you will probably soon figure it out, but this is not the thread to rehash all those unfortunate issues.
What good is it going to do us as a whole intelligence species knowing that a Earth like planet is 70 light years away with no way right now of even getting there?
Quote from: Supergravity on 02/20/2014 10:17 pm it is highly unlikely humans will ever venture into the outer parts of the solar system. You can completely forget about humans ever leaving this solar system at all, as that is essentially fantasy that only resides in the realms of science-fiction. In the far future (1000+ years from now), we may have the ability to get a probe up to 10% the speed of light and send a few to the nearest stars for scientific investigation. Supporting evidence?
it is highly unlikely humans will ever venture into the outer parts of the solar system. You can completely forget about humans ever leaving this solar system at all, as that is essentially fantasy that only resides in the realms of science-fiction. In the far future (1000+ years from now), we may have the ability to get a probe up to 10% the speed of light and send a few to the nearest stars for scientific investigation.
I realize I said never. That's simply because we pretty much have cracked all of the puzzles of fundamental physics, and any new "breakthroughs" will not at all yield any new insights that could lead to potentially revolutionary technologies.
Quote from: Supergravity on 02/20/2014 10:17 pmThe good it will do is answer a scientific question that has been bothering man since ancient times, and that question is: Are we alone?it has been bothering man since ancient times? That´s quite a bold claim, considering ancient humans did not even know about other star systems and basically, didn´t know anything about our own either.
The good it will do is answer a scientific question that has been bothering man since ancient times, and that question is: Are we alone?
Hello all, I am a avid space fanatic. I do not have any degrees nor am i a rocket scientist but I do read space news daily and I am always fascinated from documentary movies on TV. I have seen so much recent technology breakthroughs basically all aimed at new satellites which can track and detect new exoplanets and the habitat zone. But honestly... 1) What good is all that going to do? 2) Why is the main focus of the human space programs based on New faster and better propulsion engines and spacecraft? 3) What good is it going to do us as a whole intelligence species knowing that a Earth like planet is 70 light years away with no way right now of even getting there? So basically my question is two parts... 1 . 4) Why as a whole intelligence species looking to advance our propulsion to achieve new speeds for inter-space travel and 5) 2. Are we not that advance as I think we are in respect to this question on?
Maybe it's worth mentioning that the kind of theoretical breakthrough that would be required for advanced propulsion does not necessarily comes out of a big pile of money.The theory of relativity for instance came out of an humble physicist who was working in a patent office in Switzerland. Arguably, this is kind of a romantic view of physics that is not valid anymore, but still...The risk to just waste this money in the benefit of state employees and to the detriment of tax payers is big.
The basic research can be cheap, but at some point, you will have to invest more. This is why I am proposing a competition of sorts. People can submit their ideas and those that are selected get funded according to milestones.
Well yeah, that would make some sense. It's not obvious how you could come up with milestones with something like advanced propulsion, though. I mean, isn't that kind of binary? You either find something that works or you don't.PS. on second thought, I guess with fusion-powered propulsion for instance it should not be too difficult to imagine incremental steps.
Quote from: Elmar Moelzer on 02/25/2014 05:32 pmThe basic research can be cheap, but at some point, you will have to invest more. This is why I am proposing a competition of sorts. People can submit their ideas and those that are selected get funded according to milestones. Well yeah, that would make some sense. It's not obvious how you could come up with milestones with something like advanced propulsion, though. I mean, isn't that kind of binary? You either find something that works or you don't.PS. on second thought, I guess with fusion-powered propulsion for instance it should not be too difficult to imagine incremental steps.
Quote from: grondilu on 02/25/2014 05:45 pmQuote from: Elmar Moelzer on 02/25/2014 05:32 pmThe basic research can be cheap, but at some point, you will have to invest more. This is why I am proposing a competition of sorts. People can submit their ideas and those that are selected get funded according to milestones. Well yeah, that would make some sense. It's not obvious how you could come up with milestones with something like advanced propulsion, though. I mean, isn't that kind of binary? You either find something that works or you don't.PS. on second thought, I guess with fusion-powered propulsion for instance it should not be too difficult to imagine incremental steps.indeed. the first fusion drives are potentially ready for assembly of the prototypes. but when they are first brought on line they will not be much better than ion propulsion of chemical engines with gravity assists. yet at the top end of their maturity they will be fast enough for interstellar flights to the 6 or so nearest stars.the ones most likely to be the first fusion drives are projected to just be 3 or 4 times faster than voyager. there are at least two in this category that are ready for full prototyping should they find funding. these would allow fast travel anywhere inside the solar system to include really places just beyond the heliopause.but fully mature fusion; engines whose reaction chamber sustains steady state fusion instead of brief episodic fusion have a current expected top end of about .35 percent C without adding any type of augmenting technology and augmenting technology is possible as are further revisions of the estimated top end. antimatter just underwent such a revision. it actually doubled it's projected top end and the method/technology involved is also germaine to fusion engine efficiency. i already added that to my top end estimates for fusion as a matter of fact. without it the top end of fusion was 15 to 20 percent C.