Yeah. Pulling a few bacteria out of an exponentially increasing culture will save the petri dish from being overrun. Duh.
In order to stabilise Earth's population through interplanetary migration, it would be neccessary to annually export many millions of people. Not going to happen. The only way to do it is for people to exercise reproductive responsibility. A naive hope, but our only chance.
The cost of a working moonbase would be well over $300 billion dollars, and would take at least twenty years.
Did you pull those figures out of your butt, or are you quoting any particular study? The International Space Station is only going to cost a fraction of that, and that's largely due to it being a huge orbiting pork barrel. Returning to the Moon is obviously a bit beyond John Carmack just yet, but well within China's reach if they set it as a national priority.
The world has moved on since Apollo, but everybody seems stuck with the concept that spaceflight is only ever going to be a national project on a pyramid-building scale. It's still going to be expensive for quite some time, but the fact that we don't have to reinvent the wheel, compact computers, carbon fibre or Tang helps keep it a bit more affordable than the '60s NASA program.
There are several groups looking at private Moon exploration, Artemis being perhaps the most well known. I think that they are kidding themselves, but good luck to 'em.
No, seriously. Did you pull the figures out of your butt?
Well said. It is my opinion that NASA and the govt have not exactly gone out of their way (lip service aside) to help anyone develop this technology, because it is not in 'the national interest' to allow these technologies to be controlled by anyone but them. People are not going to be allowed to build their own ICBMs. The small groups doing this work are quite capable of building a working suborbital rocket on a shoestring budget in the next few years, but most of them will go bust trying to meet govt regulations on securing such technologies, which will amount to more than the cost per launch. All of which is a criminal shame, to be sure. But realistically, how do you think the military will react?
This guy's family lived in South Australia, where a fair chunk of Australia's uranium exports come from. His father worked for one of the mines. My friend was a chemistry nerd, and he made up his mind one day to turn some uranium-bearing ore into yellowcake (uranium oxide, a stage in the purification process). Purely out of scientific curiousity. It's about twice as radioactive as depleted uranium, so I wouldn't walk around with it in my pants pocket, but it's not going to kill you in a hurry. 20 years on, it didn't seem to harm my friend that much. The wooden lid to the container on the 'table' would stop any alphas, and most of the betas. I wouldn't worry about it.
Sodium, flourine, or even phosphorus, on the other hand...
I'm sure you were speaking hyperbolically, but I must say that is a rather short-sighted viewpoint. It is also reminiscent of Earthly attitudes toward fossil fuels and timber resources. Just because we, from our limited and 'primitive' perspective, consider the universe to be an ever-expanding cornucopia does not mean that our descendants will thank us for creating a profligate philosophy that they will have to deal with.
Also, keep in mind factors like the universal speed limit. We can only expand into space at a certain rate. Unless you are constantly accelerating at the leading edge of the shockfront, you will be living in a region with vast but limited resources that you must share with your fellow organisms. The resource reservoir may seem 'unlimited' by our standards, but our children a few millennia hence may not agree. For example, if the human population continues to expand at the current rate, then within a few centuries humanity will be a sphere of flesh expanding outwards at a fair percentage of the speed of light. There will always be limits to growth.
Exactly! Well put. It amuses me when I see true believers breathlessly enthusing about how the Casimir effect proves we can tap the mysterious ZPF to do useful work. All we need to do is to find a way to separate the plates again once we have extracted energy from their attraction, and bingo!
Much like we can tap the mysterious force of gravity via a falling object. All we need to do is find a way to elevate the mass again so we can repeat the process. Well, duh. In both cases the good ol' 2nd Law confirms its status as the universe's biggest party pooper.
This isn't to say that the ZPF may never be a component of some exotic future energy source. After all, we do harness gravity to produce useful work in hydro power schemes. But we indirectly rely on solar power to do the work of lifting the mass back to where it can be useful again.
There have been experimental demonstrations of the veracity of the Casimir Effect, in which two closely spaced parallel plates are driven toward each other by the pressurre created by the ZPF.
It still doesn't get around the laws of thermodynamics, however. Just becasue it's an exotic energy source doesn't mean the rules don't apply to it. It's just beloved by fringe free energy types becasue it involves the magic word 'quantum', and seems to spring from nowhere.
Perhaps some basic building blocks would have survived travel between planets, but I would hardly call such things life.
Perhaps you should read more about what the exobiologists are propsing. The Martian meteorite is supposed to contain microfossils of complete bacteria. Whether it does or not, it is this sort of interplanetary bacterial, viral, or just genetic transfer that is being theorized. It has been calculated that it is at least technically possible for life to survive the journey in a state of hibernation.
Water is the hunt not for the purpose of finding alien life, though, but rather for the purpose of seeing if Mars could support human life without us having to lug a lot of water there ourselves; it's a completely reasonable and selfish goal.
Tell that to the exobiologists who are mad keen on locating the water. It's a dual purpose.
My point is that if we really want to find life, and not just some Star Trek notion of extraordinarily similar humanoid life, we need to stop making assumptions on what it should be.
Perhaps you need to stop making assumptions about what it isn't. It is difficult to explain to anyone who hasn't done enough chemistry (which I'm assuming, on little evidence, that you have not) just how unique carbon and water properties are. Life is made possible by both the incredible, unparalleled complexity of carbon chemistry, and the unique properties (ie strength of intermolecular forces, leading to unusual solvent and thermal properties) of water. People who get all shirty about water chauvinism are seldom clued in about the reality of the situation. It's like a non-anthopologist saying that just because everyone around us communicate via language and words, it's foolish to believe that there aren't humans on the other side of the world who communicate via telepathy. Try finding anyone who actually knows something about anthropology and human society to agree.
Quite simply, life as we know it makes sense because it's all that we know.
To choose another, perhaps better, counterexample: We are quite certain that our Sun shines due to nuclear fusion. Is it foolish to assume that no other stars shine due to alternate processes? Once you know enough about the science involved, the essential nature of the processes in question become obvious.
This is not to say that alternate biochemistries are impossible. Perhaps there is something exotic in the atmosphere of Jupiter, or even some sort of low-temperature activity on Pluto, but in the inner Solar System, water wins hands down.
JPL scientists have just confirmed aquisition of signal from Odyssey after completion of its rocket firing and emergence from behind Mars. They've done it!
Now perhaps we can have/. articles posted about NASA without the dreary and predictable chorus of lame jokes about the 1999 failures.
Well, several things would seem to point to that being the most likely course of events if there is any life on Mars at all.
First and foremost, remember the Martian meteorite that reignited the whole debate? Some scientists are now theorizing that life was thrown about amongst most of the bodies of the inner Solar System in the early days. Therefore any life that did take root on any planets would have features in common. Life on Earth is water based, so any Martian life is therfore more likely to be the same.
Such statements remind me of early speculation that Mars or even Venus could be "sister planets" to Earth that humans could live on if we could just reach them.
Centuries ago, people thought the planets were gods. At least the more recent idea of sister planets was closer to the truth. Theories are continuing to evolve, and much current speculation will turn out to be wrong, but we know more that we used to.
To believe that all life requires water is equally foolish.
It's impossible to eliminate really exotic biochemistries, but in the inner Solar System water-based life has an overwhelming advantage for many of the same reasons that life is also carbon based: those chemicals are unbelievably versatile, far more so than any other form of chemistry. Liquid water has a number of properties that set it apart from other substances. Ask any chemist about hydrogen bonding and thermal properties. It makes water possibly uniquely suited to its role in life. Any alternate biology would seem unlikely within the so-called "habitable zone" around the Sun.
In order to get anywhere we need to approach the speed of light or even exceed it (or better yet, make the whole thing about space/time irrelevant, but that is sci-fi for the time being)
You ain't just whistling Dixie when you say it's science fiction. The fastest propulsion system proposed that we're fairly sure would work is Orion, which uses a chain of mini atomic bombs to get to 10% of c. Don't even think about trying to build it with todays technology. Anything else is currently just fantasy.
We don't need to get close to the speed of light for travel within the inner Solar System. If NASA felt that public opinion would tolerate it, they could use nuclear rockets, in which an atomic reactor was used to accelerate the fuel. That is the technology, which we could start building today, that will make travel to and from Mars feasible. We are not, in my opinion, going to get to Mars with conventional rockets.
Learning where the water is is a necessary prerequisite to finding what life may still exist. If there is life still there, it will be close to water. Water is easier to find that scant traces of life. Therefore, find the H2O, and you actually have a chance of finding something else.
NASA sent only two probes to Mars in the 70's, Viking 1 & 2. It has firm plans to send at least one probe every two years until at least the end of the decade. Considering the budget they operate within, I think they're doing a damn good job.
Actually, we don't, that's one of the things this probe has been sent to determine. There is an ambiguous but intriguing body of evidence that liquid water may once have flowed on Mars' surface, but what water remains is yet to be determined.
and if there is water then there must also be air
We have known for some considerable time that Mars has a very thin atmosphere composed primarily of carbon dioxide. It is less than 1% as thick as Earth's atmosphere.
If there is air, this suggests that there must be life on the Red planet.
Your chain of reasoning is getting increasingly tenuous.
By flying all these spacecraft into Mars, we may be destroying their ecosystem
Odyssey is an orbiter, not a lander. It will never come in contact with the planet. Even if the worst happens, like it did with Mars Climate Orbiter in 1999, the thin Martian atmosphere is still thick enough to ensure that nothing uncharred reaches the surface. All landers are thoroughly sterilized before leaving Earth.
I have serious problems with your reasoning. My biggest beef is that Moore's observation has lazily and incorrectly been labeled a law, when it obviously is nothing of the sort. Nature doesn't give a rat's arse about the speed of computers. The continued doubling of processor speeds is dependent on human engineering, and there are no guarantees that new advances will arrive on schedule.
moore's law, - which btw, does not simply reflect the speed of integrated circuts, but physics, biology and nanotech in general. b: exponential growth of internet population and traffic
See? This is just what I'm talking about. Moore came up with his observation years before any talk of nanotech, biochips or other buzzwords du jour. There are many promising technologies that may take us beyond current lithographic techniques, but there is no reason to believe that growth will conform to any 'law'. The pace may accelerate, or it may stall and plateau for a number of years until the next breakthough. Advances will come about because of human ingeniuty, not some over-hyped statement of current general trends.
And I'm telling you that the Russians worked out that two progress rockets expending their entire fuel supply to reboost would have only bought Mir about three years.
IANA physicist, but I'm quite sure that atmospheric pressure drops off pretty close to linearly.
Typical of the sort of instant punditry found on Slashdot - Some computer geek states that 'it could have been done' when rocket scientists (who would have dearly loved to keep it up if even remotely practicable and safe) spent months working out that it wasn't possible. I know which one I choose to have faith in.
Sorry, but I think you've been buying into a bit too much hype.
This was first seriously proposed by Gerald K. Oneill of Princeton University in 1975! It was feasable ( and even profitable ) then
No, it wasn't even remotely profitable in the 70s, just as it is not (quite) profitable now. When O'Neill made his calculations in the mid-70s, he projected several future technologies that would make his schemes affordable, the foremost being cheap, reliable, regular access to space. In 1975, the space shuttle was 7 years away from its maiden flight, and everybody believed the bullshit about the fleet flying one mission per week with perfect safety. This has not proven to be the case.
Until we get a 10-fold reduction in launch costs, and launches are handled more like airport departures, then schemes such as this will remain prohibitively expensive. I want it as much as the next geek, but I'd rather focus on what concrete steps we can take in the next 5-10 years. Cheap access is the breakthough tech.
Does anyone question that this would be a better place to be... and we could be there by now, if only we had the vision, and the will.
Of course it would be a better place to be. World peace would be nice too, but we're going to need a bit more than abstract notions of vision and will to get us there.
This whole line about 'lack of will' is one that I see quite frequently on/. from starry-eyed, impatient idealists who want to holiday on the Moon RIGHT NOW. If you try to explain about economics, technological development, or engineering project turnaround times, they frequently have problems accepting this. Not wanting to believe that they may have to wait a while to get all Buck Rogers, they cast about for the real reason, and latch on 'political will'. It was politicians that cut short the Apollo program, so it's politicians fault that there isn't currently a lunar Hilton.
Umm, no. Lack of funding (as well as bureaucratic inefficiency) may be retarding the rate of advance, but we can't blame Washington because we don't have a warp drive yet. Let's take things one step at a time. As soon as such projects become economically feasible, you can bet your bottom dollar someone will come forward with a business plan.
Well, that was kinda my point. You're asking why we aren't remote piloting submarines around Europa, and I pointed out that they're having enough difficulty getting an orbiter able to return science by the end of the decade. An orbiter is essential before any landers, in order to determine surface conditions, locate good landing spots and so on. This necessary pathfinder orbiter is currently blowing out the entire outer planets budget for the next 6-8 years. What you want would be many times more expensive and technically challenging than the existing mission that is barely keeping afloat.
"We must deal with the world as it is, not as we wish it were."
Second, get some damn probes into Europa already!!!
You are aware that NASA is working on a Europa Orbiter at the moment? It's a prime example of what's wrong with NASA.
There are a substantial number of tehcnological issues that need to be addressed before the mission is feasible. Hardened circuitry is a big one, as Europa orbits Jupiter inside the unbelievably strong radiation belts. These issues have pushed the launch of EO back from 2003 to at least 2006-08. Costs have also skyrocketed to the point that it may eat up the entire outer planets science budget.
The big problem with this is that Goldin would rather fund EO than Pluto Express, because in his opinion (contrary to many in the scientific community, but that never stoped Dan before) people aren't interested in Pluto. Europa will still be there a few years from now, but if we don't launch to Pluto really soon, then its atmosphere will freeze for another couple of centuries. Meanwhile, money could continue being poured into EO with no firm prospect of short term success.
Let's prioritize our limited space science budget to examine the stuff that we can and should reach right now.
This is why de-orbiting Mir frustrated me so greatly. Everyone though of it as an either/or situation: either burn it in, or find money to maintain it and keep it manned. No one seemed to consider the third and best option: boost it into a non-decaying orbit, and leave it there unmanned as a resource to exploit in the future.
ACtually, the RUssians considered this quite thoroughly. The problem is, even dedicating two or three Progress ships (at $20 million+ a pop) to reboost would only have bought a few years breathing space before it would have to be done again. By the time it could be smelted down on-site, you would have spent more than it was worth on reboost flights.
I'm sorry, I can see that you really want this to be plausible, but it just ain't.
. I believe that NASA's goal should not so much be a man on Mars by the end of the century, but rather a permanent supply station in Mars orbit and the first steps to a Biosphere II on a Jovian moon, by 2005.
Given that NASA is having problems finishing the ISS in that timeframe (one without the habitation module, the rebooster, and the lifeboat) it would seem optimistic in the extreme to believe that we could have major infrastructure in place around other planets at the same time.
And it is major infrastructure that you are talking about. Currently doable stuff at Jupiter runs as far as Galileo and Cassini. Not in terms of technological sophistication (both 20 year old tech), but in terms of weight that can be launched. Cassini, the heaviest space probe ever launched (5,600 kg) left Earth on a Titan IV, the most powerful expendable launcher currently in the US fleet. It still required gravity assists from Venus and Earth to get enough velocity to reach Jupiter and Saturn. You aren't going to get an awful lot of habitation room, or even engineering space, in a mass that size. Factor in the harsh radiation environment around Jupiter, the LONG flight times, and all the technological unknowns that would have to be addressed even before your proposal got approved, and 2005 looks a mite unrealistic.
. That gives you a year to build some skeletal components, and launch them. That's not a huge amount of time, but it's certainly doable.
If you were building a carbon copy of an existing module, sure. Designing one from scratch to take into account the conditions and requirements at Jupiter (such as landing on an airless moon) would take just a little bit longer.
There's nothing impossible about building combined habitat module / DS-1 in that kind of timeframe.
Given that no artificial biosphere has even got close to self-sufficiency, I think that's a bit overconfident. Keeping people alive in space with current technology is a game of keeping pace with constant equipment repairs and maintenance. It takes 2.5 crewmembers to keep the ISS habitable. Sustainable space habitats filled with life are a way off yet.
Why not go to the moon? The answer is simple. Why bother?
Beacuse it's actually doable in the next few decades. Your proposal, I'm sorry to say, simply isn't. I think your understandable impatience to see your vision realized has blinded you to the sheer quantity of R&D, money and time that will be necessary to bring it into being. Don't stop dreaming, though, because we need your enthusiasm. Just temper it with a dose of pragmatism.
Re:Aerobraking vs. Propulsion Braking
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The Art of Aerobraking
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Why not design a craft which could always 'right' itself regardless of how it is situated after it lands with a parachute type landing?
They did. It was called Mars Pathfinder. It bounced around on those big airbags for a while, and after it came to rest sequentially deflated them so the payload ended the right way up.
I think you are looking at the problems and the failures and ignoring the successes completely. Sanity lies somewhere inbetween.
No, I'm not. NASA's successes are extraordinary, but they are not miracle workers. You do them a disservice by demanding that they achieve the currently impossible. I've said this several times, but here it goes again: If NASA could do what you describe within their budgetary constraints, they would already be doing it. Or do they lack your imagination? They come up with so many innovative concepts for probes, such as Deep Impact, do you think that they can't see the benefits in a $200 million asteroid return?
the cable didn't snap, it burnt through due to high current flows.
Fair enough, you got me there. The point I was trying to make was that describing a potential technology is very different from putting it into practice. I could just as easily have questioned his plan to wrap the rock in Mylar.
ripples in mirrors degrade their efficiency, they don't stop them working.
Degrades them to the point of uselessness, perhaps. Recent investigations have called into question whether inflatable mirrors would be ripple-free enough to use as space telescopes or antennas. The problem would be orders of magnitude worse for a mirror kilometers across. Again, if we could construct that sort of structure right now without blowing out the national debt, we would probably already be planning to do it.
Slashdot Mirror
Yeah. Pulling a few bacteria out of an exponentially increasing culture will save the petri dish from being overrun. Duh.
In order to stabilise Earth's population through interplanetary migration, it would be neccessary to annually export many millions of people. Not going to happen. The only way to do it is for people to exercise reproductive responsibility. A naive hope, but our only chance.
Did you pull those figures out of your butt, or are you quoting any particular study? The International Space Station is only going to cost a fraction of that, and that's largely due to it being a huge orbiting pork barrel. Returning to the Moon is obviously a bit beyond John Carmack just yet, but well within China's reach if they set it as a national priority.
The world has moved on since Apollo, but everybody seems stuck with the concept that spaceflight is only ever going to be a national project on a pyramid-building scale. It's still going to be expensive for quite some time, but the fact that we don't have to reinvent the wheel, compact computers, carbon fibre or Tang helps keep it a bit more affordable than the '60s NASA program.
There are several groups looking at private Moon exploration, Artemis being perhaps the most well known. I think that they are kidding themselves, but good luck to 'em.
No, seriously. Did you pull the figures out of your butt?
Well said. It is my opinion that NASA and the govt have not exactly gone out of their way (lip service aside) to help anyone develop this technology, because it is not in 'the national interest' to allow these technologies to be controlled by anyone but them. People are not going to be allowed to build their own ICBMs. The small groups doing this work are quite capable of building a working suborbital rocket on a shoestring budget in the next few years, but most of them will go bust trying to meet govt regulations on securing such technologies, which will amount to more than the cost per launch. All of which is a criminal shame, to be sure. But realistically, how do you think the military will react?
...so it can't be that bad.
This guy's family lived in South Australia, where a fair chunk of Australia's uranium exports come from. His father worked for one of the mines. My friend was a chemistry nerd, and he made up his mind one day to turn some uranium-bearing ore into yellowcake (uranium oxide, a stage in the purification process). Purely out of scientific curiousity. It's about twice as radioactive as depleted uranium, so I wouldn't walk around with it in my pants pocket, but it's not going to kill you in a hurry. 20 years on, it didn't seem to harm my friend that much. The wooden lid to the container on the 'table' would stop any alphas, and most of the betas. I wouldn't worry about it.
Sodium, flourine, or even phosphorus, on the other hand...
I'm sure you were speaking hyperbolically, but I must say that is a rather short-sighted viewpoint. It is also reminiscent of Earthly attitudes toward fossil fuels and timber resources. Just because we, from our limited and 'primitive' perspective, consider the universe to be an ever-expanding cornucopia does not mean that our descendants will thank us for creating a profligate philosophy that they will have to deal with.
Also, keep in mind factors like the universal speed limit. We can only expand into space at a certain rate. Unless you are constantly accelerating at the leading edge of the shockfront, you will be living in a region with vast but limited resources that you must share with your fellow organisms. The resource reservoir may seem 'unlimited' by our standards, but our children a few millennia hence may not agree. For example, if the human population continues to expand at the current rate, then within a few centuries humanity will be a sphere of flesh expanding outwards at a fair percentage of the speed of light. There will always be limits to growth.
Exactly! Well put. It amuses me when I see true believers breathlessly enthusing about how the Casimir effect proves we can tap the mysterious ZPF to do useful work. All we need to do is to find a way to separate the plates again once we have extracted energy from their attraction, and bingo!
Much like we can tap the mysterious force of gravity via a falling object. All we need to do is find a way to elevate the mass again so we can repeat the process. Well, duh. In both cases the good ol' 2nd Law confirms its status as the universe's biggest party pooper.
This isn't to say that the ZPF may never be a component of some exotic future energy source. After all, we do harness gravity to produce useful work in hydro power schemes. But we indirectly rely on solar power to do the work of lifting the mass back to where it can be useful again.
Oops. Looked at the new-fangled post ID rather than user ID. We both posted the same link, though, so I still call jinx!
Wow. Same post time, and user IDs just 3 numbers apart!
I call jinx!
There have been experimental demonstrations of the veracity of the Casimir Effect, in which two closely spaced parallel plates are driven toward each other by the pressurre created by the ZPF.
It still doesn't get around the laws of thermodynamics, however. Just becasue it's an exotic energy source doesn't mean the rules don't apply to it. It's just beloved by fringe free energy types becasue it involves the magic word 'quantum', and seems to spring from nowhere.
The Simpsons did one a number of years ago about Armour Hotdogs and Chicken Tonight. They've done the Pillsbury Doughboy. I'm sure there are more.
Perhaps you should read more about what the exobiologists are propsing. The Martian meteorite is supposed to contain microfossils of complete bacteria. Whether it does or not, it is this sort of interplanetary bacterial, viral, or just genetic transfer that is being theorized. It has been calculated that it is at least technically possible for life to survive the journey in a state of hibernation.
Tell that to the exobiologists who are mad keen on locating the water. It's a dual purpose.
Perhaps you need to stop making assumptions about what it isn't. It is difficult to explain to anyone who hasn't done enough chemistry (which I'm assuming, on little evidence, that you have not) just how unique carbon and water properties are. Life is made possible by both the incredible, unparalleled complexity of carbon chemistry, and the unique properties (ie strength of intermolecular forces, leading to unusual solvent and thermal properties) of water. People who get all shirty about water chauvinism are seldom clued in about the reality of the situation. It's like a non-anthopologist saying that just because everyone around us communicate via language and words, it's foolish to believe that there aren't humans on the other side of the world who communicate via telepathy. Try finding anyone who actually knows something about anthropology and human society to agree.
To choose another, perhaps better, counterexample: We are quite certain that our Sun shines due to nuclear fusion. Is it foolish to assume that no other stars shine due to alternate processes? Once you know enough about the science involved, the essential nature of the processes in question become obvious.
This is not to say that alternate biochemistries are impossible. Perhaps there is something exotic in the atmosphere of Jupiter, or even some sort of low-temperature activity on Pluto, but in the inner Solar System, water wins hands down.
Go talk to a biochemist.
JPL scientists have just confirmed aquisition of signal from Odyssey after completion of its rocket firing and emergence from behind Mars. They've done it!
Now perhaps we can have /. articles posted about NASA without the dreary and predictable chorus of lame jokes about the 1999 failures.
Well, several things would seem to point to that being the most likely course of events if there is any life on Mars at all.
First and foremost, remember the Martian meteorite that reignited the whole debate? Some scientists are now theorizing that life was thrown about amongst most of the bodies of the inner Solar System in the early days. Therefore any life that did take root on any planets would have features in common. Life on Earth is water based, so any Martian life is therfore more likely to be the same.
Centuries ago, people thought the planets were gods. At least the more recent idea of sister planets was closer to the truth. Theories are continuing to evolve, and much current speculation will turn out to be wrong, but we know more that we used to.
It's impossible to eliminate really exotic biochemistries, but in the inner Solar System water-based life has an overwhelming advantage for many of the same reasons that life is also carbon based: those chemicals are unbelievably versatile, far more so than any other form of chemistry. Liquid water has a number of properties that set it apart from other substances. Ask any chemist about hydrogen bonding and thermal properties. It makes water possibly uniquely suited to its role in life. Any alternate biology would seem unlikely within the so-called "habitable zone" around the Sun.
In order to get anywhere we need to approach the speed of light or even exceed it (or better yet, make the whole thing about space/time irrelevant, but that is sci-fi for the time being)
You ain't just whistling Dixie when you say it's science fiction. The fastest propulsion system proposed that we're fairly sure would work is Orion, which uses a chain of mini atomic bombs to get to 10% of c. Don't even think about trying to build it with todays technology. Anything else is currently just fantasy.
We don't need to get close to the speed of light for travel within the inner Solar System. If NASA felt that public opinion would tolerate it, they could use nuclear rockets, in which an atomic reactor was used to accelerate the fuel. That is the technology, which we could start building today, that will make travel to and from Mars feasible. We are not, in my opinion, going to get to Mars with conventional rockets.
Learning where the water is is a necessary prerequisite to finding what life may still exist. If there is life still there, it will be close to water. Water is easier to find that scant traces of life. Therefore, find the H2O, and you actually have a chance of finding something else.
NASA sent only two probes to Mars in the 70's, Viking 1 & 2. It has firm plans to send at least one probe every two years until at least the end of the decade. Considering the budget they operate within, I think they're doing a damn good job.
Actually, we don't, that's one of the things this probe has been sent to determine. There is an ambiguous but intriguing body of evidence that liquid water may once have flowed on Mars' surface, but what water remains is yet to be determined.
We have known for some considerable time that Mars has a very thin atmosphere composed primarily of carbon dioxide. It is less than 1% as thick as Earth's atmosphere.
Your chain of reasoning is getting increasingly tenuous.
Odyssey is an orbiter, not a lander. It will never come in contact with the planet. Even if the worst happens, like it did with Mars Climate Orbiter in 1999, the thin Martian atmosphere is still thick enough to ensure that nothing uncharred reaches the surface. All landers are thoroughly sterilized before leaving Earth.
I have serious problems with your reasoning. My biggest beef is that Moore's observation has lazily and incorrectly been labeled a law, when it obviously is nothing of the sort. Nature doesn't give a rat's arse about the speed of computers. The continued doubling of processor speeds is dependent on human engineering, and there are no guarantees that new advances will arrive on schedule.
See? This is just what I'm talking about. Moore came up with his observation years before any talk of nanotech, biochips or other buzzwords du jour. There are many promising technologies that may take us beyond current lithographic techniques, but there is no reason to believe that growth will conform to any 'law'. The pace may accelerate, or it may stall and plateau for a number of years until the next breakthough. Advances will come about because of human ingeniuty, not some over-hyped statement of current general trends.
And I'm telling you that the Russians worked out that two progress rockets expending their entire fuel supply to reboost would have only bought Mir about three years.
IANA physicist, but I'm quite sure that atmospheric pressure drops off pretty close to linearly.
Typical of the sort of instant punditry found on Slashdot - Some computer geek states that 'it could have been done' when rocket scientists (who would have dearly loved to keep it up if even remotely practicable and safe) spent months working out that it wasn't possible. I know which one I choose to have faith in.
Sorry, but I think you've been buying into a bit too much hype.
This was first seriously proposed by Gerald K. Oneill of Princeton University in 1975! It was feasable ( and even profitable ) then
No, it wasn't even remotely profitable in the 70s, just as it is not (quite) profitable now. When O'Neill made his calculations in the mid-70s, he projected several future technologies that would make his schemes affordable, the foremost being cheap, reliable, regular access to space. In 1975, the space shuttle was 7 years away from its maiden flight, and everybody believed the bullshit about the fleet flying one mission per week with perfect safety. This has not proven to be the case.
Until we get a 10-fold reduction in launch costs, and launches are handled more like airport departures, then schemes such as this will remain prohibitively expensive. I want it as much as the next geek, but I'd rather focus on what concrete steps we can take in the next 5-10 years. Cheap access is the breakthough tech.
Of course it would be a better place to be. World peace would be nice too, but we're going to need a bit more than abstract notions of vision and will to get us there.
This whole line about 'lack of will' is one that I see quite frequently on /. from starry-eyed, impatient idealists who want to holiday on the Moon RIGHT NOW. If you try to explain about economics, technological development, or engineering project turnaround times, they frequently have problems accepting this. Not wanting to believe that they may have to wait a while to get all Buck Rogers, they cast about for the real reason, and latch on 'political will'. It was politicians that cut short the Apollo program, so it's politicians fault that there isn't currently a lunar Hilton.
Umm, no. Lack of funding (as well as bureaucratic inefficiency) may be retarding the rate of advance, but we can't blame Washington because we don't have a warp drive yet. Let's take things one step at a time. As soon as such projects become economically feasible, you can bet your bottom dollar someone will come forward with a business plan.
Well, that was kinda my point. You're asking why we aren't remote piloting submarines around Europa, and I pointed out that they're having enough difficulty getting an orbiter able to return science by the end of the decade. An orbiter is essential before any landers, in order to determine surface conditions, locate good landing spots and so on. This necessary pathfinder orbiter is currently blowing out the entire outer planets budget for the next 6-8 years. What you want would be many times more expensive and technically challenging than the existing mission that is barely keeping afloat.
Couldn't have put it better myself.
You are aware that NASA is working on a Europa Orbiter at the moment? It's a prime example of what's wrong with NASA.
There are a substantial number of tehcnological issues that need to be addressed before the mission is feasible. Hardened circuitry is a big one, as Europa orbits Jupiter inside the unbelievably strong radiation belts. These issues have pushed the launch of EO back from 2003 to at least 2006-08. Costs have also skyrocketed to the point that it may eat up the entire outer planets science budget.
The big problem with this is that Goldin would rather fund EO than Pluto Express, because in his opinion (contrary to many in the scientific community, but that never stoped Dan before) people aren't interested in Pluto. Europa will still be there a few years from now, but if we don't launch to Pluto really soon, then its atmosphere will freeze for another couple of centuries. Meanwhile, money could continue being poured into EO with no firm prospect of short term success.
Let's prioritize our limited space science budget to examine the stuff that we can and should reach right now.
ACtually, the RUssians considered this quite thoroughly. The problem is, even dedicating two or three Progress ships (at $20 million+ a pop) to reboost would only have bought a few years breathing space before it would have to be done again. By the time it could be smelted down on-site, you would have spent more than it was worth on reboost flights.
I'm sorry, I can see that you really want this to be plausible, but it just ain't.
Given that NASA is having problems finishing the ISS in that timeframe (one without the habitation module, the rebooster, and the lifeboat) it would seem optimistic in the extreme to believe that we could have major infrastructure in place around other planets at the same time.
And it is major infrastructure that you are talking about. Currently doable stuff at Jupiter runs as far as Galileo and Cassini. Not in terms of technological sophistication (both 20 year old tech), but in terms of weight that can be launched. Cassini, the heaviest space probe ever launched (5,600 kg) left Earth on a Titan IV, the most powerful expendable launcher currently in the US fleet. It still required gravity assists from Venus and Earth to get enough velocity to reach Jupiter and Saturn. You aren't going to get an awful lot of habitation room, or even engineering space, in a mass that size. Factor in the harsh radiation environment around Jupiter, the LONG flight times, and all the technological unknowns that would have to be addressed even before your proposal got approved, and 2005 looks a mite unrealistic.
If you were building a carbon copy of an existing module, sure. Designing one from scratch to take into account the conditions and requirements at Jupiter (such as landing on an airless moon) would take just a little bit longer.
Given that no artificial biosphere has even got close to self-sufficiency, I think that's a bit overconfident. Keeping people alive in space with current technology is a game of keeping pace with constant equipment repairs and maintenance. It takes 2.5 crewmembers to keep the ISS habitable. Sustainable space habitats filled with life are a way off yet.
Beacuse it's actually doable in the next few decades. Your proposal, I'm sorry to say, simply isn't. I think your understandable impatience to see your vision realized has blinded you to the sheer quantity of R&D, money and time that will be necessary to bring it into being. Don't stop dreaming, though, because we need your enthusiasm. Just temper it with a dose of pragmatism.
They did. It was called Mars Pathfinder. It bounced around on those big airbags for a while, and after it came to rest sequentially deflated them so the payload ended the right way up.
What's a 'sustainable' atmosphere?
No, I'm not. NASA's successes are extraordinary, but they are not miracle workers. You do them a disservice by demanding that they achieve the currently impossible. I've said this several times, but here it goes again: If NASA could do what you describe within their budgetary constraints, they would already be doing it. Or do they lack your imagination? They come up with so many innovative concepts for probes, such as Deep Impact, do you think that they can't see the benefits in a $200 million asteroid return?
Fair enough, you got me there. The point I was trying to make was that describing a potential technology is very different from putting it into practice. I could just as easily have questioned his plan to wrap the rock in Mylar.
Degrades them to the point of uselessness, perhaps. Recent investigations have called into question whether inflatable mirrors would be ripple-free enough to use as space telescopes or antennas. The problem would be orders of magnitude worse for a mirror kilometers across. Again, if we could construct that sort of structure right now without blowing out the national debt, we would probably already be planning to do it.