This has less chances of freezing up, only one valve to worry about and no nasty easy leaking hydrogen. This is something that is really cool for probes and long term missions.
Better ion thrusters would be useful, but not for this reason. A long duration mission would have to use an RTG power source, which keeps the spacecraft nice and warm. Cassini has had no problems with its bipropellant thrusters. It has been out in the cold for a long time. Also, bipropellant thrusters do not use hydrogen. They use stable, storable compounds like UDMH and Nitrogen Tetroxide.
While how much 'fuel' it takes to get to the moon may be a physical law, there is absolutely nothing in physics that says how much the fuel must cost, or what form it might take.
True, but rockets that launch payloads to LEO or GTO for the forseeable future (100 years) will be chemically fueled. The best fuels that we can practically use for the forseeable future are H2 and O2 or Kerosene and O2. There is no easy way around it. What are your alternatives?
While you do, indeed, have to push X amount of stuff downward to move upward, nothing says that has to be 'fuel', as in, the stuff powering the pushing does not have to be the same stuff that you are throwing out the back. Maybe it's air you merely accelerated,
Amusing. And what would that stuff be? Air (and fuel!) get you to about 100,000 ft and Mach 3, but I'll agree it has a high Isp. What about the other 22 mach? Do you use magic pixie dust or warp power?
at least for the first part of the trip, maybe it's a load of highly compressed dirt you fling downward using electrity. Dirt is free, and electricity is cheap.
So you want to use dirt as the working fluid of an ion engine? It is not as easy to ionize as conventional fluids like Xenon. Electric power onboard an accending rocket is pretty scarce for what you are suggesting
Or maybe you use a launcher on earth that gives you a lot of momentum 'for free' (by 'pushing' the earth), or maybe you use a space elevator that gives you it all for free.
The Earth's rotation is about 1,100 mph. That leaves only 16,500 mph to be obtained from the rocket lauched eastward from the equator. Low latitude launches are efficient, but they don't help that much.
There is that pesky 'space elevator' again. Well, after all, this is slashdot.
And no matter what you throw out the back, space travel can't help but get cheaper, because spacehips are getting cheaper and lighter. 200,000 is how much it costs to put people and their part of the ship into orbit, and their part of the ship weighs a lot more than they do.
Virgin Galactic is conducting suborbital flights. They will require orders of magnitude more energy to reach orbit.
I know! And $3500 for one of these huge honking cell phone things [about.com]? Give me a break. That's only a toy for the political elite. We have about as much chance of sub-orbital flights sold only to those who can afford to $200,000 ride leading to commercial spaceflight for the rest of us as we do of seeing an affordable cell phone, computers, air travel, etc.
Comparing the evolution of space technology to consumer electronics is a laughable analogy. With space launches you are running up against a little thing called fuel mass fraction. It takes a big rocket to go to the moon. There is no way around that, even for Burt Rutan.
This is really exciting times. A private spaceport is emerging, and the "real" exploration of space can begin. I cant wait until my first moon-vacation;D
So you think the real exploration of space begins with millionaires the political elite taking $200,000 ballistic rocket rides? There is a fair technological difference between the Virgin Atlantic's proposed service and NASA's new lunar exploration program. If it was anyone other than Burt Rutan behind this I would be even more skeptical, but I do think Virgin Galactic will fly.
The close-ups showed that 10 million nerve endings tunnel from the tusk's core toward its outer surface, [and can] detect subtle changes of temperature, pressure, particle gradients and probably much else.
Nothing wrong with that. Your knowledge of networking and graph theory is immediately applicable. Demand for your services is inelastic and resistant to outsourcing.
Most everyone of my friends is a studying to be an engineer. I think the reality is that we are graduating its just taking longer then 4 years these days. I know its taking some people up to 6-7 years in a 4 year program to actually graduate. Most of this has to do with horrible advisors in my opinion.
What a terrible attitude! As an adult you are expected (heavens!) to make some choices about you future, and project your life a few years out. You expect someone else too? Maybe a year in the real world would cure your Catcher in the Rye immaturity. The 7 year program was made for people like you. Enjoy those student loan payments.
You should not assumptions about how long I have been around free software. I have been using it since RMS released GNU/Emacs in 1988, gcc in 1989, and used GNU/Linux for the first time in 1995. I am right on about Torvalds.
Linus is increasingly 'out there' in his hyperbolic statements. First the BitKeeper fiasco, now the start of a new Gnome/KDE flamewar. Ever read his daily postings on kernel trap? They are obnoxious. I am surprised the kernel effort holds together as well as it does. I personally take his statements on Gnome as anti-advice. He is becoming a most unsafe guardian. Can anyone imagine who would lead the kernel effort if Linus was shoved aside?
It is hard to get excited about bleeding edge graphics cards, because ATI and NVidia refuse to publish their register sets so people can write good free Linux drivers. I have programmed ARM, Blackfin, and PIC processors. In all cases the registers are exhaustively documented and there are thriving communities of experts trying to get the most out of them. Your $600 video card's drivers were probably developed by a team of 4. Is the code any good? You will never know. Thanks for nothing ATI and NVidia.
Hayabusa was a very innovative and daring mission. I think it bodes well for Japanese planetary missions in the future. But they really made a mess of the mission operationally. It seemed to me the planning showed lower proficiency than US missions. Expect them to improve.
This is a very nice collection. I think Cormen and Rivest's Algorithms Book would be a nice addition. It prefers pseudocode to Knuth's MIX and so it is easier to create implementations in high level languages. What is missing are: Books on X Windows Programming (assuming O'Reilly still publishes them), OpenGL (Programmer's Guide and Reference), Books on Lisp/Scheme (SICP, SAP, Common Lisp by Steele, Dyvbig). Numerical Recipies in C (one of the great books of all time).
I am a software engineer in Bangalore, and honestly I find this "contest" a bit condescending.
Ya think?
I mean, why should I jump through hoops to work at Microsft? If I wanted to work at a large company, I can apply to Oracle, Sun, IBM, Yahoo or Google (all of whom have development centres in Bangalore).
So you are saying that although you would not drop your shorts for Bill Gates, you would happily do so for Larry Elison or Scott McNealy? Gandi's ashes are spinning in their urn.
You don't deserve to be upmodded for this post. You should be flogged.
We've gained a lot of knowledge, albeit, not quite the knowledge intended to gain, gained nonetheless.
We have learned to construct a sizeable structure in space using equipment that will not exist in 5 years. ISS is the most criminal waste of money in the name of science of all time.
The iss is a platform for developing and testing long duration mission technology. The goal is to reach the point where the technology for a mars mission exists (it doesn't today), and has been tested in the harsh environment of space
The occupants aboard ISS aren't testing anything. They are marooned campers trying desperately to keep alive between resupply flights. The Russians shouldn't be involved at all considering their negative progress in democracy, human rights, and nuclear proliferation.
The iss itself is not an initial experiment in low orbit long duration, Mir already showed us that can be done, it carried on in that role for 15 years. ISS is a platform for hosting more advanced experiments and development.
Mir was a veritable carnival of danger - spacecraft collisions, explosive decompression, deadly fires. It taught the US never participate again in Russian lead ventures.
The ISS is proably going to die uncompleted. The biggest lesson learned for most of the partners, dont depend on the usa when large expenditure projects are involved, projects that extend beyond the 4 year election cycle hence they become suceptible to the short term political cycles of the usa.
Blame it on the USA. Perhaps it is going to die because our partners (besides the Russians) don't have manned space programs at all. The program has survived 25 years, 4 presidents, and $100G in funding. Seems to me that is consistent enough. The US deorbit its modules and walk for the program. That would leave a Russian module and the Canada arm remaining.
But, the bottom line, if the program is not capable of managing completion of the ISS, then there's no way it's going to produce a manned mission to mars that operates without resupply for the timeframes involved.
The assembly of ISS was very well managed by NASA. It is gone perfectly. The problem is they must use the most dangerous manned space vehicle ever launched.
Tech startup stock option millionaire dropouts engineers are a rarity these days. One of their tendencies is to cement their genius reputation by publishing a personal account of their heroics and lamenting the sad decline of the company - after cashing out ofcourse. Good examples are Mark Andreesen, Jamie Zewinski, and Andy Hertzfeld? Any others?
If I did you wouldn't know the difference, apparently. This is ok reference on the East Africa Rift. And this talks about abandoned arms. This talks about membrane stresses and fault angles. I could go on. Just google on "triple junction", "failed arm", "rift system", etc. What I said really is geology 101. You simply can't spread along 3 axes. Afar may flood with sea water, but it will never be an ocean basin as the original article suggests.
The Afar area is a triple junction where upwelling magma is driving 3 continental crust apart - the Arabian plate, West Africa and East Africa. The plates crack in 120 deg pieces because the configuration relieves plate extensional stress with minimal displacement. What typically happens when the basin expands is that one of arms is abandoned, again for thermodynamic reasons. Spreading along a single great circle requires less membrane deformation of the outer crust than spreading along 3. The principle of least action at work. In this case the active arms of the triple junction are the Red Sea and the East Indian ocean which are sites of rapid spreading of oceanic crust. Th East Africa Rift is clearly spread more slowly than the active arms and will fail. The North Sea, Mississipi delta, Camaroon rift, Connecticut Valley, etc are examples of rift valleys and failed arm abandonment during the opening of ocean basins. Sure, volcanism and rifting can still occur in the failed arm. The extensional faults that define these areas assures this. We see this in Afar, and deeper in the African rift. Camaroon is another example. The triple function there opened 120 Mya and it is still active. But is will never form a wide ocean basin. Afar tectonics are still a very interesting phenomen.
Pick your code word: utopian, communist, un-American. Proponents of free software are used to it. The cause manages to advance. Your labels don't constitute a debate. You denegrate zealotry and embrace moderation without knowing why. Muzzy thinking is nothing to be proud of.
By the way, "hacker culture" is no longer "cool". It's a pathetic group of people who can't come to grips with modern technology and simply scream (well post) from their basement about how the world misuses the world "hacker" and doesn't give their command line the respect it deserves.
Better that than a clueless drooler who willingly tithes to a vile corporation who shits on the world, and uses them as a surrogate for their thinking. (I expect the standard reply, Bill Gates is worth $50 gazillion, how much are your worth?...)
Slashdot has been shilling every skank Microsoft framework, language, and 'technology' for months now. It is an eyesore to those of us who have come here for free software news. Moderators, why do you accept these submissions? Don't you see that you are polluting hacker culture? Are you succombing to pressure by Microsoft's advertising dollars?
Enemy 'Command and control' was the first and most important target in the Gulf Wars. Cyberwarfare is another rapid means of attacking it out, along with jamming, and good old iron bombs. I for one welcome our new Air Force overlords.
While the Chinese failure was tragic you cannot discount an entire program over 1 failure. I don't agree with their government's handling of the situation just like I don't agree with the NASA's beaurocracy. They have made some great progress.
But I do. They bought a Soyuz spacecraft from Russia and are dancing in the streets after flying it on a simplistic mission is if it was their own. Their booster design is also Soyuz like in size and configuration. When they do the least thing in original fashion, I'll take notice. Chinese propaganda is effective apparently.
Thats because Russia has a manned space program (you catching the drift yet?)
Russia has been gun shy about planetary missions ever since the dismal failure of their Phobos mission. They are rumoured to want in on Europe's Bepi-Columbo mission to Mercury if it ever flies. The Russian space program is becoming less impressive all the time. They have been waiting for better days for 35 years.
and Japan doesn't pump nearly as many dollars into spaceflight as NASA or RSC, or even ESA. But Japan does have some cool tech wrt. VTVL SSTO's. At least they are doing something unique.
I am not aware of the unique things Japan doing. They flew some toy hypersonic craft in Australia recently, which was similar to but less impressive than NASA's scramjet test last year. Their asteroid mission was pretty innovative, but they made a real mess of it operationally.
What unique cool things has the ESA really done?
I am usually critical of Europe, but the radar sounding results they are returning from Mars Express are amazing. Totally unique. They are the rough equivalent of seizmic profiles. The US will be copying it.
Spend $50 to buy a hardware firewall and the life expectancy of your laptop will skyrocket
Spend $0, install a GNU/Linux or xBSD distribution, your laptop will be immortal, and you will never have to devote another brain cell to this silly discussion. You'll be promoting the freedom of ideas as well.
Slashdot Mirror
This has less chances of freezing up, only one valve to worry about and no nasty easy leaking hydrogen. This is something that is really cool for probes and long term missions.
Better ion thrusters would be useful, but not for this reason. A long duration mission would have to use an RTG power source, which keeps the spacecraft nice and warm. Cassini has had no problems with its bipropellant thrusters. It has been out in the cold for a long time. Also, bipropellant thrusters do not use hydrogen. They use stable, storable compounds like UDMH and Nitrogen Tetroxide.
1984? Then it must be morning in America. Thank you President Reagan!
While how much 'fuel' it takes to get to the moon may be a physical law, there is absolutely nothing in physics that says how much the fuel must cost, or what form it might take.
True, but rockets that launch payloads to LEO or GTO for the forseeable future (100 years) will be chemically fueled. The best fuels that we can practically use for the forseeable future are H2 and O2 or Kerosene and O2. There is no easy way around it. What are your alternatives?
While you do, indeed, have to push X amount of stuff downward to move upward, nothing says that has to be 'fuel', as in, the stuff powering the pushing does not have to be the same stuff that you are throwing out the back. Maybe it's air you merely accelerated,
Amusing. And what would that stuff be? Air (and fuel!) get you to about 100,000 ft and Mach 3, but I'll agree it has a high Isp. What about the other 22 mach? Do you use magic pixie dust or warp power?
at least for the first part of the trip, maybe it's a load of highly compressed dirt you fling downward using electrity. Dirt is free, and electricity is cheap.
So you want to use dirt as the working fluid of an ion engine? It is not as easy to ionize as conventional fluids like Xenon. Electric power onboard an accending rocket is pretty scarce for what you are suggesting
Or maybe you use a launcher on earth that gives you a lot of momentum 'for free' (by 'pushing' the earth), or maybe you use a space elevator that gives you it all for free.
The Earth's rotation is about 1,100 mph. That leaves only 16,500 mph to be obtained from the rocket lauched eastward from the equator. Low latitude launches are efficient, but they don't help that much.
There is that pesky 'space elevator' again. Well, after all, this is slashdot.
And no matter what you throw out the back, space travel can't help but get cheaper, because spacehips are getting cheaper and lighter. 200,000 is how much it costs to put people and their part of the ship into orbit, and their part of the ship weighs a lot more than they do.
Virgin Galactic is conducting suborbital flights. They will require orders of magnitude more energy to reach orbit.
I know! And $3500 for one of these huge honking cell phone things [about.com]? Give me a break. That's only a toy for the political elite. We have about as much chance of sub-orbital flights sold only to those who can afford to $200,000 ride leading to commercial spaceflight for the rest of us as we do of seeing an affordable cell phone, computers, air travel, etc.
Comparing the evolution of space technology to consumer electronics is a laughable analogy. With space launches you are running up against a little thing called fuel mass fraction. It takes a big rocket to go to the moon. There is no way around that, even for Burt Rutan.
This is really exciting times. A private spaceport is emerging, and the "real" exploration of space can begin. I cant wait until my first moon-vacation ;D
So you think the real exploration of space begins with millionaires the political elite taking $200,000 ballistic rocket rides? There is a fair technological difference between the Virgin Atlantic's proposed service and NASA's new lunar exploration program. If it was anyone other than Burt Rutan behind this I would be even more skeptical, but I do think Virgin Galactic will fly.
You mean like a tooth?
and now I am considering retraining as a plumber.
Nothing wrong with that. Your knowledge of networking and graph theory is immediately applicable. Demand for your services is inelastic and resistant to outsourcing.
Most everyone of my friends is a studying to be an engineer. I think the reality is that we are graduating its just taking longer then 4 years these days. I know its taking some people up to 6-7 years in a 4 year program to actually graduate. Most of this has to do with horrible advisors in my opinion.
What a terrible attitude! As an adult you are expected (heavens!) to make some choices about you future, and project your life a few years out. You expect someone else too? Maybe a year in the real world would cure your Catcher in the Rye immaturity. The 7 year program was made for people like you. Enjoy those student loan payments.
You should not assumptions about how long I have been around free software. I have been using it since RMS released GNU/Emacs in 1988, gcc in 1989, and used GNU/Linux for the first time in 1995. I am right on about Torvalds.
Linus is increasingly 'out there' in his hyperbolic statements. First the BitKeeper fiasco, now the start of a new Gnome/KDE flamewar. Ever read his daily postings on kernel trap? They are obnoxious. I am surprised the kernel effort holds together as well as it does. I personally take his statements on Gnome as anti-advice. He is becoming a most unsafe guardian. Can anyone imagine who would lead the kernel effort if Linus was shoved aside?
It is hard to get excited about bleeding edge graphics cards, because ATI and NVidia refuse to publish their register sets so people can write good free Linux drivers. I have programmed ARM, Blackfin, and PIC processors. In all cases the registers are exhaustively documented and there are thriving communities of experts trying to get the most out of them. Your $600 video card's drivers were probably developed by a team of 4. Is the code any good? You will never know. Thanks for nothing ATI and NVidia.
Hayabusa was a very innovative and daring mission. I think it bodes well for Japanese planetary missions in the future. But they really made a mess of the mission operationally. It seemed to me the planning showed lower proficiency than US missions. Expect them to improve.
This is a very nice collection. I think Cormen and Rivest's Algorithms Book would be a nice addition. It prefers pseudocode to Knuth's MIX and so it is easier to create implementations in high level languages. What is missing are: Books on X Windows Programming (assuming O'Reilly still publishes them), OpenGL (Programmer's Guide and Reference), Books on Lisp/Scheme (SICP, SAP, Common Lisp by Steele, Dyvbig). Numerical Recipies in C (one of the great books of all time).
I am a software engineer in Bangalore, and honestly I find this "contest" a bit condescending.
Ya think?
I mean, why should I jump through hoops to work at Microsft? If I wanted to work at a large company, I can apply to Oracle, Sun, IBM, Yahoo or Google (all of whom have development centres in Bangalore).
So you are saying that although you would not drop your shorts for Bill Gates, you would happily do so for Larry Elison or Scott McNealy? Gandi's ashes are spinning in their urn.
You don't deserve to be upmodded for this post. You should be flogged.
We've gained a lot of knowledge, albeit, not quite the knowledge intended to gain, gained nonetheless.
We have learned to construct a sizeable structure in space using equipment that will not exist in 5 years. ISS is the most criminal waste of money in the name of science of all time.
The iss is a platform for developing and testing long duration mission technology. The goal is to reach the point where the technology for a mars mission exists (it doesn't today), and has been tested in the harsh environment of space
The occupants aboard ISS aren't testing anything. They are marooned campers trying desperately to keep alive between resupply flights. The Russians shouldn't be involved at all considering their negative progress in democracy, human rights, and nuclear proliferation.
The iss itself is not an initial experiment in low orbit long duration, Mir already showed us that can be done, it carried on in that role for 15 years. ISS is a platform for hosting more advanced experiments and development.
Mir was a veritable carnival of danger - spacecraft collisions, explosive decompression, deadly fires. It taught the US never participate again in Russian lead ventures.
The ISS is proably going to die uncompleted. The biggest lesson learned for most of the partners, dont depend on the usa when large expenditure projects are involved, projects that extend beyond the 4 year election cycle hence they become suceptible to the short term political cycles of the usa.
Blame it on the USA. Perhaps it is going to die because our partners (besides the Russians) don't have manned space programs at all. The program has survived 25 years, 4 presidents, and $100G in funding. Seems to me that is consistent enough. The US deorbit its modules and walk for the program. That would leave a Russian module and the Canada arm remaining.
But, the bottom line, if the program is not capable of managing completion of the ISS, then there's no way it's going to produce a manned mission to mars that operates without resupply for the timeframes involved.
The assembly of ISS was very well managed by NASA. It is gone perfectly. The problem is they must use the most dangerous manned space vehicle ever launched.
Tech startup stock option millionaire dropouts engineers are a rarity these days. One of their tendencies is to cement their genius reputation by publishing a personal account of their heroics and lamenting the sad decline of the company - after cashing out ofcourse. Good examples are Mark Andreesen, Jamie Zewinski, and Andy Hertzfeld? Any others?
If I did you wouldn't know the difference, apparently. This is ok reference on the East Africa Rift. And this talks about abandoned arms. This talks about membrane stresses and fault angles. I could go on. Just google on "triple junction", "failed arm", "rift system", etc. What I said really is geology 101. You simply can't spread along 3 axes. Afar may flood with sea water, but it will never be an ocean basin as the original article suggests.
I am a geophysicist by training. I think most experts would agree with me.
The Afar area is a triple junction where upwelling magma is driving 3 continental crust apart - the Arabian plate, West Africa and East Africa. The plates crack in 120 deg pieces because the configuration relieves plate extensional stress with minimal displacement. What typically happens when the basin expands is that one of arms is abandoned, again for thermodynamic reasons. Spreading along a single great circle requires less membrane deformation of the outer crust than spreading along 3. The principle of least action at work. In this case the active arms of the triple junction are the Red Sea and the East Indian ocean which are sites of rapid spreading of oceanic crust. Th East Africa Rift is clearly spread more slowly than the active arms and will fail. The North Sea, Mississipi delta, Camaroon rift, Connecticut Valley, etc are examples of rift valleys and failed arm abandonment during the opening of ocean basins. Sure, volcanism and rifting can still occur in the failed arm. The extensional faults that define these areas assures this. We see this in Afar, and deeper in the African rift. Camaroon is another example. The triple function there opened 120 Mya and it is still active. But is will never form a wide ocean basin. Afar tectonics are still a very interesting phenomen.
Pick your code word: utopian, communist, un-American. Proponents of free software are used to it. The cause manages to advance. Your labels don't constitute a debate. You denegrate zealotry and embrace moderation without knowing why. Muzzy thinking is nothing to be proud of.
By the way, "hacker culture" is no longer "cool". It's a pathetic group of people who can't come to grips with modern technology and simply scream (well post) from their basement about how the world misuses the world "hacker" and doesn't give their command line the respect it deserves.
Better that than a clueless drooler who willingly tithes to a vile corporation who shits on the world, and uses them as a surrogate for their thinking. (I expect the standard reply, Bill Gates is worth $50 gazillion, how much are your worth?...)
Slashdot has been shilling every skank Microsoft framework, language, and 'technology' for months now. It is an eyesore to those of us who have come here for free software news. Moderators, why do you accept these submissions? Don't you see that you are polluting hacker culture? Are you succombing to pressure by Microsoft's advertising dollars?
Enemy 'Command and control' was the first and most important target in the Gulf Wars. Cyberwarfare is another rapid means of attacking it out, along with jamming, and good old iron bombs. I for one welcome our new Air Force overlords.
While the Chinese failure was tragic you cannot discount an entire program over 1 failure. I don't agree with their government's handling of the situation just like I don't agree with the NASA's beaurocracy. They have made some great progress.
But I do. They bought a Soyuz spacecraft from Russia and are dancing in the streets after flying it on a simplistic mission is if it was their own. Their booster design is also Soyuz like in size and configuration. When they do the least thing in original fashion, I'll take notice. Chinese propaganda is effective apparently.
Thats because Russia has a manned space program (you catching the drift yet?)
Russia has been gun shy about planetary missions ever since the dismal failure of their Phobos mission. They are rumoured to want in on Europe's Bepi-Columbo mission to Mercury if it ever flies. The Russian space program is becoming less impressive all the time. They have been waiting for better days for 35 years.
and Japan doesn't pump nearly as many dollars into spaceflight as NASA or RSC, or even ESA. But Japan does have some cool tech wrt. VTVL SSTO's. At least they are doing something unique.
I am not aware of the unique things Japan doing. They flew some toy hypersonic craft in Australia recently, which was similar to but less impressive than NASA's scramjet test last year. Their asteroid mission was pretty innovative, but they made a real mess of it operationally.
What unique cool things has the ESA really done?
I am usually critical of Europe, but the radar sounding results they are returning from Mars Express are amazing. Totally unique. They are the rough equivalent of seizmic profiles. The US will be copying it.
Spend $50 to buy a hardware firewall and the life expectancy of your laptop will skyrocket
Spend $0, install a GNU/Linux or xBSD distribution, your laptop will be immortal, and you will never have to devote another brain cell to this silly discussion. You'll be promoting the freedom of ideas as well.