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Plasma Propulsion Could Cut Time To Mars in Half
NEW ROCKET TECHNOLOGY COULD CUT MARS TRAVEL TIME
An agreement to collaborate on development of an advanced rocket technology that could cut in half the time required to reach Mars, opening the solar system to human exploration in the next decade, has been signed by NASA's Johnson Space Center, Houston, TX, and MSE Technology Applications Inc., Butte, MT.
The technology could reduce astronauts' total exposure to space radiation and lessen time spent in weightlessness, perhaps minimizing bone and muscle mass loss and circulatory changes.
Called the Variable Specific Impulse Magnetoplasma Rocket (VASIMR), the technology has been under development at Johnson's Advanced Space Propulsion Laboratory. The laboratory director is Franklin Chang-Diaz, a NASA astronaut who holds a doctorate in applied plasma physics and fusion technology from the Massachusetts Institute of Technology, Cambridge.
Chang-Diaz, who began working on the plasma rocket in 1979, said, "A precursor to fusion rockets, the VASIMR provides a power- rich, fast-propulsion architecture."
Plasma, sometimes called the fourth state of matter, is an ionized (or electrically charged) gas made up of atoms stripped of some of their electrons. Stars are made of plasma. It is gas heated to extreme temperatures, millions of degrees. No known material could withstand these temperatures. Fortunately, plasma is a good electrical conductor. This property allows it to be held, guided and accelerated by properly designed magnetic fields.
The VASIMR engine consists of three linked magnetic cells. The forward cell handles the main injection of propellant gas and its ionization. The central cell acts as an amplifier to further heat the plasma. The aft cell is a magnetic nozzle, which converts the energy of the fluid into directed flow.
Neutral gas, typically hydrogen, is injected at the forward cell and ionized. The resulting plasma is electromagnetically energized in the central cell by ion cyclotron resonance heating. In this process radio waves give their energy to the plasma, heating it in a manner similar to the way a microwave oven works.
After heating, the plasma is magnetically exhausted at the aft cell to provide modulated thrust. The aft cell is a magnetic nozzle, which converts the energy of the plasma into velocity of the jet exhaust, while protecting any nearby structure and ensuring efficient plasma detachment from the magnetic field.
A key to the technology is the capability to vary, or modulate, the plasma exhaust to maintain optimal propulsive efficiency. This feature is like an automobile's transmission which best uses the power of the engine, either for speed when driving on a level highway, or for torque over hilly terrain.
On a mission to Mars, such a rocket would continuously accelerate through the first half of its voyage, then reverse its attitude and slow down during the second half. The flight could take slightly over three months. A conventional chemical mission would take seven to eight months and involve long periods of unpowered drift en route.
There are also potential applications for the technology in the commercial sector. A variable-exhaust plasma rocket would provide an important operational flexibility in the positioning of satellites in Earth orbit.
Several new technologies are being developed for the concept, Chang-Diaz said. They include magnets that are super-conducting at space temperatures, compact power generation equipment, and compact and robust radio-frequency systems for plasma generation and heating.
Coordinated by Johnson's Office of Technology Transfer and Commercialization, the Space Act Agreement calls for a joint collaborative effort to develop advanced propulsion technologies, with no money exchanged between the two parties. Such agreements are part of NASA's continuing effort to transfer benefits of public research and development to the private sector.
Variable Specific Impulse Magnetoplasma Rocket does not become VASIMR as the article states.
According to proper acronymology, the true acronym should be VSIMR. If they chose the more inferior, VASIMR, for phonetic reasons, then they are a disgrace to the Russian Language.
Keeping
It's great to see research being done on this things. However I wish that Nasa/JPL could get the funding to pursue this more fully.
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This woman sounds like a prime candidate to be one of the first test monkeys for the VASIMR system.
before some idiot straps one to four wheels and tries to break mach 2 on the salt flats?
And better yet: How long after leaving the line before same fool disintegrates the car and is strewn over fifty square miles of ground?
.sig: Now legally binding!
Even though this technology would cut the time to Mars in half you can bet that the kids would still spend the whole time whining.
"Are we there yet?"
Nasa's simply going to have to do better :).
How fast would the space craft be going at the halfway point when it would turn around to slow down?
Anyone know of a physical limit to the speed of this type of craft?
I checked the link, and I'm sorry if I missed it, but I didn't seem to spot speed numbers anywhere.
Wheeeee
i seem to recall hearing something similar to this quite a while ago, it was about ion drives... seems like the scientists used zillions of charged particles directed out of the spacecraft by a large magnet for propulsion. each particle supposedly gave the equivalent thrust of the weight of a piece of paper. What's the difference, besides the fact that these particles are really really really hot?
-freakingmoron- Have you ever imagined a world without hypothetical situations?
This is good to hear. Cutting travel times to Mars in half is a big deal, actually. I mean, the shorter travel times are, the more feasible it is to explore other parts of the solar system. I'm not even looking at the prospect of colonization here, but I would very much like to see us mining the asteroid belt and stuff like that. I don't think it would be terribly cheap to mine the asteroids and ship ore back to Earth, but at the same time, when we use up our resources here, it would be nice to have the capability to go find more elsewhere in the system.
Well, this is definitely a boost for the hopes of manned exploration of Mars, which means that this technology will almost certainly not be used to it's full potential.
It constantly astounds me that world governments, with all the obvious environmental problems, refuse to whole-heartedly endorse space programs. Certainly, the lack of participation of nations in the shape of Russia (although their space program is/was generally good) is understandable, but the U.S. and other prosperous countries need to take some leadership here.
An Internation Space Station is a good start, but the political infighting regarding the development of it is discouraging. We need governments to realize that, with 6 billion people on the earth, that we don't have the resources to maintain an acceptable standard of living infinitely.
Traveling to another planet to explore, in a precursor to either inhabitation or mining, would be an even better use of this technology. I for one hope that world governments wake up (and that waking up is continigent upon public sentiment) and realize that right now is the time to radically advance our exploration of space.
Scythe
50,000 degrees. That is HOT and I mean that is ten times hotter than the surface of the Sun, (the Sun's core is over 7,000,000K). What are the materials proposed to sustain that kind of heat? I mean even if electromagnetic fields will be used in order to contain the plasma, what kind of isolators will we need for this to work? Is it going to be all carbonated ceramics, damasked with layers of pure carbon and then asbestos and then meters of iron cooled by liquid oxygen? I tell ya, it would be cool enough to run a Beowulf Cluster of some twenty Pentium III processors!
Seriously enough, does anyone know how to support 50,000K temperature with known materials?
You can't handle the truth.
Sure, in a race between the two the plasma rocket sounds like it would win--by a long shot.
But if I want to be on Mars ASAP, which technology is going to get me there first? Conventional, tried-and-true, already-exists rockets? Or untested, not-yet-mature, haven't-built-one-yet technology?
Just launch a damn ship NOW.
--
Compaq dropping MAILWorks?
Linux MAPI Server!
http://www.openone.com/software/MailOne/
(Exchange Migration HOWTO coming soon)
We could only wish... cutting mars in half would lead us to heavenly oceans of caramel... -Ryan
Scientific American ran a really detailed article a few months back on Mars missions. It discussed several propulsion systems, including this plasma thingee.
If I understand the way this works, there is not enough thrust to get outside of the van allen belts quickly, and thus the people inside the spaceship would be fried. This is a problem with all of the burn long but hot spaceships.
Strap some variable-exhaust plasma rockets on my car and call me George Jetson...
with this latest develpment, i can't wait to hear astronauts reporting back to houston,about "we need to vent the plasma conduits" :>
maybe next they'll build a main deflector array, which can discharge tacheon bursts and low level graviton pulses
Live EVERY week... Like it's Shark Week
Basically, is having a plasma rocket inherently more dangerous to be launching through the atmoshpere than the normal chemical rockets currenntly employed?
Lastly, I guess is the bit about "large magnets that are super-conductive in space temeperatures" imply that these rockets may not be able to leave orbit in order to keep the engine functional (or have massive amounts of cooling available to take over for atmoshperic descent).
--sugarman--
I wonder how bulky it is, I get the feeling it'll be big. Getting it into space would be expensive, perhaps manufacturing in orbit would be ideal.
:)
If its not too large, I'd like to propose making a plasma gun ala Doom and Q3a.
'Neutral gas, typically hydrogen' neutral meaning 'non-ionised' I suppose. At least it fits with Elite and the hydrogen fuel suggested there
-Yarn - Rio Karma: Excellent
Personally I think they should be trying to develop the McAndrew balanced drive because:
At 100Gs, I've had longer naps...
Vacuum energy, no waste save the planet!
Compressed matter disks, amaze your friends!
Seriously, as the worlds largest Chuck Sheffield fan, you should all go out to Borders and buy and read The Compleat McAndrew. Chuck has been so kind as to collect all these stories into one place, so we can be kind enough to buy it.
What are you waiting for? Get thee to Borders!
Most of my friends who majored in plasma physics got jobs writing computer programs that have nothing to do with plasma. It is a really cool field w/o much applications. Creating plasma on earth is sometimes a dark science. You build your equipment (sometimes out of old microwave oven tubes) and hope to god it works. One of my friends made the mistake of taking apart his plasma generator -- darn thing never worked again. Maybe in the future if it gives us cold fusion but until then most of the graduate become computer programers :)
Seriously though. Are they going to take all of the propelent with them or will they collect it along the way. This is still going to take massive amounts of energy. Are they going to bring a tiny nuclear power plant with them? I suspect the enviromental people will be up in arms over this. People seem to get upset every time the word nuclear is mentioned. It will be quite a while before this is put into practice (if at all.) Hopefully it will be in our lifetime.
Under capitalism man exploits man. Under communism it's the other way around.
Seriously. Why we so worried about Mars when we ain't done jack on the moon? Where's that moon base I've heard talk about since 4th grade?
Until we get some people doing something productive on the moon for an appreciable length of time, I think we oughta leave Mars on the back burner.
-JimTheta
My stupid web site
Scientific American had a serries of articles on this here
A few questions for any aerospace geeks that want to take a shot: How efficient and how safe would a plasma powered engine be inside of the atmosphere? They mentioned that this kind of rocket could be used to life satellites, so it apparently would work surrounded by air. Could this kind of rocket lift off from Florida and fly directly to Mars? Most of the Mars plans that I have read involve a craft built, or at least refueled, at the ISS (and I'm not holding my breath until that thing is fully functional).
-B
If the craft's continual acceleration is great enough then they could use the g-force to simulated gravity. .5 way point and just before/after the take off/landing.
The only time there would be 0g is when they turn the ship around at the
Health would no longer be such a big concern.
-----
If my facts are wrong then tell me. I don't mind.
That got me excited as I never thought I would see that in my lifetime.
Today's vices may be tomorrow's virtues.
Yeah! They could implant the system in her butt, 'cause she won't be using it for dancing any more.
Of course, they have to provide visuals. think of the wonder of a 3 month, million-degree fart!
Does this mean that now we can truthfully say "We need to vent the plasma from the impulse engines!"? (I know, I know, in Star Trek the plasma is in the warp engines...:)
Seriously though, this seems neat. It seems alot like the ion engines they put on one of those probes (can't remember which). But then, those are from Star Wars (TIE==Twin Ion Engines). It seems like the main differences are that the plasma is superheated, and they're using H instead of Xe. Does anyone know how superheating the stuff affects thrust?
--
Seeing is believing; You wouldn't have seen it if you didn't believe it.
Do you really think this is finally going to make go to Mars? I don't. Call me pessimistic, but the Ignorant Masses do not have the enthusiasm for space anymore to make the politicians back an manned Mars Mission. I really, truly hope that I am wrong, this is the kind of mission that we need. I just don't think that it is going to happen. In a few years, this will all have faded away, and some will wonder, "What happened? Why aren't we out there?"
Ciao.
nahtanoj
So now we can wait for NASA to save up enough money to build one, then spend ten years "researching" the project, or some hotshot venture capitalist who wants to be a space cowboy build one and launch it from a mobile platform in the middle of the Pacific sometime late next week. Outstanding!
B
"I'm payin' taxes, but what am I buyin'?" -- James Brown
Rush down to your local blood center and donate some of your plasma!
count to ten
XML causes global warming.
I just made 40 bucks donating some plasma at the blood bank yesterday!
I'm glad to be part of the effort.
Save the whales. Feed the hungry. Free the mallocs.
I've said this before in a reply post, but here goes... The actual spacecraft employing a plasma drive will probably still have normal chemical booster rockets for stages I, II, up to whatever. My guess is that the plasma drive will only be used once clear of Earth. Therefore, no danger to Earth/people. The plasma Drive is actually very efficient compared to the rockets in use today, i'm hoping i get to see them in common use soon.
-freakingmoron- Have you ever imagined a world without hypothetical situations?
Way back when, there was this project to go to mars with a craft that used nukes detonated in an elliptic shield. It was planned, engineers and computer scientists were hired to figure out the details (I know this because the genius of a Dino I learned from was actually one of the comp sci types on the project), and it was actually found to be feasible with a reasonable budget and surplus nukes. Then the public got wind of it and didn't like the 'n' word...
Now we're talking about a plasma that doesn't look much less radiative for the crew, given the relative strengths of the ships, and certainly costs more, and goes slower... decades later... and it's a great thing? What's in a name? Nuclear == bad, plasma != bad? Mind you, the Orion project, like all space travel back then, would have used the technological equivalent of duct tape and bailing wire. Sometimes I wish I were a geek of yore...
-- Still waiting for the Nike endorsement
Isn't he the "I kiss you!" guy?
Save the whales. Feed the hungry. Free the mallocs.
http://www.sciam.com/2000/0300issue/0300alpert.htm l
In particular, you might want to compare the methods available, including this excellent candidate:
http://www.sciam.com/2000/0300issue/0300alpertbo x2.html
Right now, I'd put my money on the test proven nuclear rocket. VASMIR, though excellent, needs a power source to make it work and the best candidate for that now is a fission reactor!
I Need More MegaWatts.
Wait a minute. There is no ship, there is no ISS, there is no team. It was supposed to be done, on its way, or at least close, but there is only a steadily diminishing effort being put forth by underfunded space agencies who are only becoming more underfunded. We aren't really trying to reach Mars, or even Earth orbit. The only real long-term space settlement is Mir. Why was it allowed to fall into disrepair in the first place? If there was money for maintenence, this wouldn't have happened. But Russia doesn't have enough money for everything, and no one is helping them. The dream is moving forward, but it is dying.
Decades ago, an observer of the Apollo mission announce that "Now we must go to Mars!" But there have been so many setbacks, so many buget cuts... politicians do what will get them reelected. And the people who are reelecting them don't care enough about space to want their governments to spend valuble tax dollars on it. Most of the news about actual work in space today relates to commercial ventures. That's sad.
We can only do so much with one planet. All the scientific advancement in the world can only go so far. Sure, a society could eventually be created that would be adapted to living forever on Earth and Earth only, but that's just not in human nature. Space is the future, and it will provide for the advancement of humanity far better than one poor planet on its own ever could. We can only go so far before we've taken all we can from the Earth and it decays even faster than it is now.
We need to embrace the space program, not act like short sighted prairie dogs (are prairie dogs shortsighted?). Convince your friends. Then maybe we can get back on track (or at least try... we were supposed to have a colony on Mars by now....)
it's green.
... a year or so ago. Very cool technology, one of NASA's (JPL I believe) most interesting recent launches.
:) I'm sure you could grep it yourself if you're interested.
Its an ion-propulsion driven deep space explorer - it does not use plasma fusion.
Ion propulsion is a very weak (for now) method of getting around, and yes - in the DS1 experiment, it doesn't provide much more force than the weight of paper here on Earth, but gradually over time DS-1 will reach incredible speeds.
There's more about DS-1 on the NASA pages, but I'm too lazy to go find a link for you!
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --
I went to the Johnson Space Center in Houston where Dr Chang-Diaz had his laboratory at the time. He conducted a tour and showed off the test engine they were doing research on. The cool thing was the big round magnets situated around the cylindrical assembly. Reminded me very much of a warp coare on it side. Another thing Dr Chang-Diaz mentioned not in the article, was that the strong magnetic field given off by the magnets in a full scale engine, would generate a large magnetic field around the ship, which he speculated might be useful for deflecting dust and micro-meteorites during the voyage. He was a really smart guy and very eager to show off all his work during the tour.
There are lots of ways to play with plasmas to create engines. NASA did lots of research into this in the 60's, and then someone decided it wasn't a good idea to launch a nuclear reactor, and research basically stopped. The technology has been around for a long time though (arcjets, ion engines, electrostatic engines of various designs...)
The fact of the matter is you could build a craft the size of the shuttle that could make it to Mars and back on one tank of gas, but it would require a nuclear reactor on board. You can also collect interplanetary dust (99% hydrogen) and use it as fuel. Greenpeace, our political system, and the public in general don't like nuclear reactors. I've fantasized many times about buying an island in the pacific for the purpose of building a launch complex, and being out of the reach of governments that feel it's their duty to make sure they know where every ounce of radioactive material on the planet is, and exactly what the owner is doing with it.
Nuclear "fear" is responsible for so much...export controls on computers, testban treaties, greenpeace...but there's so much you could do with it if you could get around all the (MASSIVE) regulation.
All research on nuclear technology basically stopped in this country in the 60's. France, for instance, has far more advanced (and safe) nuclear power plants than the US because they kept working on them. At some point in this country it became taboo to have anything to do with nuclear technology.
It's sad how ignorance and fear are the driving force behind policy on this issue. *sigh*
--Bob
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
Q: Is there a reason that the Martian landscape, a completely different planet, so strikingly resembles the Arizona desert? (you bet your butt there is)
Q: Why do liberals find it so decidedly convenient to distract schoolchildren with prophetic nonsense about "other planets" instead of focusing their attention on the here and now where it belongs? Lots of topics of education are being outright ignored in favor of liberal subjects such as astronomy, evolution, and heliocentrism.
Mike Roberto (roberto@soul.apk.net) -GAIM: MicroBerto
Berto
There are still two major problems with using plasma propulsion on interplanetary missions. First, the spacecraft probably will still require a large mass of hydrogen fuel. There is not going to be a magic solution to the problem of accelerating the huge mass of a rocket. Second, the spacecraft is going to need a lot of energy to heat the plasma with radio waves and to maintain a magnetic field. This is the same problem that prevents cold fusion from being effective. Either the rocket will need a nuclear reactor, which the enviornmentalists will never go for (think about the Cassini protests times 10), or the rocket will need even more fuel which will add to the first problem. I can't see plasma propulsion being an effective solution.
I was under the impression this technology had been developed along with the original ion drive. If you want more information on thrust comparisons between the avaliable engines, check out the March 2000 issue of Scientific American.
The best part of the VASIMR system comes from the first word in it's acronym: Variable. The thrust can be adjusted such that you can aim for speed, or you can aim to push a heavy payload. It's like having an engine that works in a Ferrari, and after minimal adjustment, works in a Semi.
Despite the promise of this system, it will require other technology. In low gear, it would take 2.1 days to escape our planet's gravity well. In high gear, an un-bearable 53 days. So, we still face a problem. Either we need to build our crafts in space, such as Utopia Planitia in Star Trek, or we need to find a cheaper launch alternative that is akin to the 21 minute burn time required by a chemical rocket.
Still, this method is only good for interplanetary travel. If we want to go to the next star system, the most efficient means of travel within our grasp is that of a Solar Sail. NASA plans on testing a carbon composite sail in 2010 that, if succesful, would make speeds approaching 10% of the great c, possible. That means it would only take 40 years to reach Proxima Centauri. A 4 generation trip, there and back. Thats pretty good.
Pax Digitalia
the space probe they sent to saturn to sample the gasses before they refreeze for a very long time used this kind of drive.
it was launched late 98 and i think it was on slashdot...
Shut up brain or I'll stab you with a Q-Tip. - Homer Simpson
Can someone with a clue answer this. What type of matter is used as the source for the plasma? What do they turn into plasma? How much would it take to get to Mars?
I would think it'd take more effort to establish a self-sustaining base on the Moon than it would on Mars, given the limited resources to be found on the Moon.
But, the advantage to the Moon is the proximity to Earth - if things go wrong, its just a 3 day trip to the plentiful resources of Earth.
So, we refine the self-sustaining tech needed to live on Mars, using our own backyard lab (the Moon), and once that's all happening, send the tech off to Mars. Not to mention that we could probably *manufacture* half of the Mars base from the Moon, which would be cheaper and less dangerous than doing it here on Earth. Heck, we could probably use all sorts of crazy ass tech on the moon to build things better, such as nuclear technology, etc.
Seems sorta backwards to me that we're ignoring this resource and trying to get straight to Mars instead, but then again I don't know how these things are budgeted. Perhaps there are political reasons for getting th Mars before doing the Moon thing - and after all, politics drive the space program.
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --
If this technology proves to be flawless and is able to be implemented in a cost effective manor. I think you will see more funding and research behind it. The global implications of colonizating/terraforming Mars are obvious and have been looked at for many years. The only unfortunate thing is that each planet would be cut off from each other. THis technology, however, now puts us one step closer to achieving that.
"Imagination is the only weapon in the war against reality." -Jules de Gautier
Wow, then I suppose a matter-antimatter plasma manifold type propulsionsystem can't be far off. I was thinking something that altered subspace around the ship in a sort of "warp" bubble, oh wait...that sounds kind of familiar.
Execute? [Y/N] _
So do I hook myself to an I.V. and have a centrifuge spin out the red cells? Will the red cells be restored when I hit the brakes for my approach to Mars? I hope so. I'd hate to spend my first few days in the Martian atmosphere suffering from anemia too.
--
As a matter of fact, I am a lawyer. But I play an actor on TV.
no aliens would dare mess with earth if it were possible :)
"Imagination is the only weapon in the war against reality." -Jules de Gautier
This engine design reminds me a lot of the fusion pulse engines used in the Space Sci-fi series by Kim Stanley Robinson called Red Mars, Green Mars, Blue Mars. I just wonder how long it will take to develop compact power generator, and those superconducting magnets.
Are those neat plasma wrist rests still going to work at 50,000 degrees, in this new state of matter? Wouldn't you burn your wrists?
--- "So THAT's what an invisible barrier looks like!" - Time Bandits
This is great and all but the most fundamental difference between this engine and a chemical rocket is that the energy source is electric instead of chemical, and that that energy has to come from somewhere.
It's interesting that in none of the press releases do they mention that any ship using this propulsion system would need to have a fair sized nuclear pile (likely more than Cassini's 76 pounds of plutonium) to generate the electricity needed.
Deep Space's ion drive, while having an incredible specific impulse, was pushing so little fuel at any given time that a moderate power source would work. If we're talking about driving 100 tons of cargo to Mars in a speed race however, it's going to require far, far more electricity than a solar cell could reasonably capture, and forget batteries. They can't store enough, even if they weren't damned heavy.
I'm not saying it's for better or worse, but the fact that this propulsion system would mean launching large amounts of plutonium atop a chemical rocket to get out of the Earth's gravity well shouldn't be overlooked or swept under the rug. The potential for disaster is there.
Kevin Fox
Kevin Fox
Apparently there is some vented frustrations here. Do you actually think they'll pass up the opportunity to spend billions of dollars on flights of fancy? I mean spending money down on earth isn't quite the 'in' thing to do lately, and frankly I don't blame anyone. If you'd like the world to change, let's not blame it on a bunch of politicians, change it yourself.
Seems sorta backwards to me that we're ignoring this resource and trying to get straight to Mars instead, but then again I don't know how these things are budgeted. Perhaps there are political reasons for getting th Mars before doing the Moon thing - and after all, politics drive the space program.
Well said. I personally hate the space program. If we're not gonna spend that kind of heavy cash down here where it will do the most good, we should at least work toward useful applications instead of jumping to the next big media event.
"Hey look! We found a new planet! Give us money, attention, and fame!" Shut up, dork, and put a Burger King somewhere we can actually get to. Then get back to me.
-JimThetaMy stupid web site
He wants to liberate grammar-error from its enslavement at the hands of the despotical Slashdot!
You capitalist swine.
DNA just wants to be free...
There is another reason you left out. With a low -thrust engine, the only way to get up would be to circle around the earth gaining speed and altitude. However, you have to get through the air resistance for this to work.
Hmm, maybe a ship with low-speed wings would work, so it would just climb steeply at low speed. Still, don't forget about the fuel that hovering takes. If you're hovering, your engine is 0% efficient, since you aren't gaining any kinetic or potential energy, but you're expending fuel energy. I think this is why the space shuttle blasts off straight up with a whole lot of power, instead of going up more gradually.
#define X(x,y) x##y
#define X(x,y) x##y
Peter Cordes ; e-mail: X(peter@cordes ,
For us (anyone, not just NASA/Americans, but the world) to go out into space?
I love the space program. I loved watching the first man land on the moon when I was a kid. I still get exited when the space shuttle goes up, the Hubble returns photographs, or we get some fuzzy gray reminder that Voyager is still out there - (the real one, not Janeway's).
It would be neat to go to Mars, to send manned expeditions to the asteroid belt, to build larger ships and stations offworld in Earth orbit or to build a permanent presence on the Moon.
The problem is money, time and most of all interest. We no longer have the Russians and Americans competeting for space. We no longer want to know things for the sake of knowing them. We know longer encourage young people to be an astronaut or a scientist like we did in the 50's and 60's. Most of our great labs are closed or shrinking for lack of funds.
We have forgotten that many of the things we take for granted, micro-electronics as in PC's, were the direct result of their need in the space program in the 60's and 70's, for instance. It becomes too indirect to convince the average joe/liberal/conservative/flat earther of the benefits of space travel.
Of course there is the constant argument of "What about our problems here on Earth?". I find myself agreeing with that sentiment and attempt to spend part of every day trying to figure out a way to eradicate two thirds of the world's human population without leaving an ecological disaster behind for out plant and animal friends - Joke, son, its a joke, you know,ha-ha..
But seriously, maybe it is time we really started a grass roots effort to remind the world how proud and unified we felt as a human family when we, as a race, stepped onto the Moon. How? I dunno, I believe activism means moving from my computer/car to the car/refrigerator.
I think I will only vote for persons with a record of supporting an active and agressive space program. I will write regular emails to news organizations asking why American news media covers space news less than their Eurpean counterparts. I think I will inquire about investments into private companies that focus on space-related businesses.
That can be my start, what do you want to do?
Anyone else agree or am I way off here?
I know that i would like to see the moon someday. If this plasma deal cuts the trip to Saturn down, I can see us getting everything done faster. All in all, it's good to know that the government is doing something to help business.
This appears to be a variation on the Ion engine that was so effective in DeepSpace 1. No, you're not going to get much of a thrust off of it in any hour or so, but you're going to get more overall through the course of the trip because it's continual. Sorry, no Mach 2 rocket cars for this engine.
It would be much more realistic to compare performance between this and an Ion engine instead of a chemical rocket. Ion engines are a proven technology which is jets ionized Xenon instead of Hydrogen plasma. Xenon is safer to carry, but nearly impossible to collect en-route.
What I want to know is where they're getting the continual stream of power to generate the radio waves to create this plasma. This isn't trivial, and power generating and storage systems take up weight.
Mythological Beast
Wake up - the future is arriving faster than you think.
Man. I ate a plate of beans that produced results that sound a lot like the term Variable Specific Impulse Magnetoplasma.
"A sample size of one is really just statistical masturbation."
b) they're gonna demo a 10 kilowatt version and expect it to scale by 3 orders of magnitude?
c) What's the point in doing this when all the really good stuff is on the asteroids anyway- and asteroids are stuffed full of this neat fuel called, wait for it, WATER (which incidentally makes a really great radiation shield...) and they have loads of rare metals, like URANIUM. Hey that's handy ;-)
d) this system pisses away power like crazy- throwing exhaust away at 30km/s is actually too fast... very little of the energy ends up in the spacecraft almost all of it goes into the exhaust. Unless you have energy to burn you probably don't need the speed.
e) check out the link above- the timetable to get the nuclear reactor that big in space doesn't happen till 2020... with conventional technology we could be there in 5 years- 10 if we stop off at the asteroids- and asteroids can actually generate revenue.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"constant thrust = constant acceleration
Most likely in a practical Mars-bound craft it'd be around 1 or 2 Gs for most of the trip.
Sudden weightlessness when the engines cut out and as the ship turns around.
Make sure everyone's holding onto the floor real quick, and kick in the engines again. Back at a constant 1 or 2 Gs.
DNA just wants to be free...
I have the book, and have gotten partway through. But I ran square against his anti-space-station bigoted attitude, and found it hard to get past after a while. Maybe his Mars proposal doesn't need a space station. Maybe that's a good point of it. But the fact is, it's partly up there, now. At the moment, it's even planned to be finished. So at the moment, it's useless to rant against the space station while making a Case For Mars. But it seems to me that that's what Zubrin was doing. Maybe after the Service Module is up, and the thing isn't in imminent danger of de-orbit, I'll pick the book back up and read. Besides, if someone wanted to 'terminate the station now and save the money for Mars,' and made a pursuasive enough case, perhaps they could stop it. But I'm sure the 'saved money' would not be used to go to Mars. There's quite a bit on sci.space.tech about how 'off-the-shelf' stuff usually isn't really. Space travel really is HARD.
The living have better things to do than to continue hating the dead.
Someone with moderator points can mod up things they've posted as an AC.
The cake is a pie
why are we so intent on outsurviving the Earth's willingness to let us live here?
My guess is that 1- people don't like to think that all our evolutionary gene-jockeying will ultimately be for naught and 2- we're thinking about how un-fun it would be to watch the end of the planet/solar system/galaxy/universe, and so turn to sci-fi and NASA to find a way to run away, even if we only prolong the inevitable.
Don't get me wrong, though, I'm with the explorers on this one. I'd loooove to go to Mars, or anywhere else for that matter...anybody read "Fountains of Paradise"? I don't think it's too far-fetched that we'll inhabit other planets eventually. The question is, are we going to become the locusts of the universe, gobbling up resources and then moving on? We're doing a good job of that here...
The Divine Creatrix in a Mortal Shell that stays Crunchy in Milk
The House Between - Original Sci-Fi Series
The difference between +5 and "Redundant" around here is about 10 seconds. :)
Save the whales. Feed the hungry. Free the mallocs.
Is good to know that finaly they're going to do it, I've known Mr. Chan-Diaz for a while and at the begining nobody wanted to listen to him... he had to fight for resources and time, but is good to hear that he's really doing it know...
By the way, for all of you who said a few days ago that 3th world people needed to know how to read before they can use the web Dr. Frankling Chan Diaz is from Costa Rica, he was born in Costa Rica, raised in Costa Rica and went to University of Costa Rica also... so what do you think about us now... and he's not the only one that smart...
Costa Ricans also have some patents in the US for the memory mesh of the old but great Wang Computers and some other stuff.
It's not like my life is so fabulous anyway . . . worst case scenario is that I get killed. Best case scenario is that I end up doing a Good Deed. Since I can get myself killed just crossing the street, I don't see a problem here.
I have no
Where's the dangerous radiation here? We're just talking about ions, particularly normal hydrogen-1 ions. There's no fission. There's no fusion. They're just stripping off the electrons and telling it to go "vrooom" out the ass end. Now maybe if you mention the fact that it works on similar principles to those of commercial microwave ovens, then you might scare someone, but it's still nonionizing radiation, and those people are still idiots.
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
It's too bad that nothing much happened after the commendable Tom Hanks film, Apollo 13 , unlike Saving Private Ryan which helped get the ball rolling on the WW2 Memorial.
By all means, this is an issue to keep in mind during the coming election campaign. Simply ask the candidates where they stand on NASA funding, and let them paint themselves as either populist tax-cutters or visionary opportunists.
Stop by my site where I write about ERP systems & more
> Yes - humans lack the physical and psychological power to view the awesome site of Mars.
Mars has an awesome site? mars.org? no, I guess not. Maybe you were talking about the sight of mars.
#define X(x,y) x##y
#define X(x,y) x##y
Peter Cordes ; e-mail: X(peter@cordes ,
Note to story poster: The first two words of the headline are invisible unless highlighted in light mode due to the color tag.
<FONT COLOR="#FFFFFF">Book Reviews</FONT>
>The supervolcano under Yellowstone park
I'd never heard of such a thing before. I'd thought you were kidding at first, but google has turned up a couple of nifty sites I've been looking at.
Is there anyplace in particular for lots of GOOD detail on this supervolcano and others (if any( like it?
Links would be greatly appreciated.
thanx
john
Resistance is NOT futile!!!
Haiku:
I am not a drone.
Remove the collective if
Imagine all the people...
in a closed system, the entropy will INCREASE. continuously and consistently.
and the sun doesn't provide us with entropy, the sun is what keeps us from being overwhelmed by entropy. it provides energy.
earth is not a closed system, and the sun is one of the major contributors of change.
eventually the entropy level of the universe will reach a point where life cannot exist and the entire universe will become one evenly distributed goopy mess of nothing. it's called heat-death kiddies; look it up. very depressing stuff.
Power Corrupts
Just a quick question... where do our friendly neighbourhood scientists intend to get the 10MW of power required to make this thing work? If the Orion project was thrown off by way of the fact that it was based on nuclear explosions, and other systems based on nuclear tech have been ignored, what's the alternative power source for those big-ass magnets that are needed to make this thing work? I'm sure NASA won't be sending up tons of premagnetized ferrite - there has to be a massive amount of electricity involved in both the generation of the plasma, its containment and its controlled expulsion, and the solar panels for just 100kW of power (according to SciAm) are "unwieldy". That's a full two orders of magnitude less than is needed here.
Ideas anyone?
It would be almost impossible to live on it too. Probably the only sources of energy are nuclear and solar- and solar is weaker than earth; nuclear would have to be delivered for quite a while.
It's also mega expensive to get there and back (although cheaper than escaping from the earths gravity); and nobody has the slightest clue how to make any money there.
I can see that going there would be mega cool; but the asteroids are actually a better bet, and closer in many dimensions including cost, distance, velocity and time. Returning an asteroid to the earth would actually be useful- we could build technology like satellites and even return mined platinum group metals to the earth- they are worth $400/ounce right now!
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"Troll...
BlackNova Traders
This is very cool and I would love to see it pan out for the same reason others would, this place is becoming quite crowded. To paraphrase Lazarus Long "Anyplace that you need a ID card to prove who you are is too crowded and too oppressive." For anyone interested in this sort of thing (and most geeks are) visit the Living Universe Foundation @ www.luf.org The make some good points about where to start this ball rolling. Is manking really ready for the difficulies of space-life when we have yet to populate 2/3 of this planet? The seas would be a great training ground (so to speak)
-- Hail Eris
This comment is totally without merit.
The whole point of advanced propulsion systems is to have faster exaust.
A high-velocity exhaust means you need less reaction mass to achieve the same change in spacecraft velocity. Or put another way, you can go faster with the same amount of reaction mass.
News Flash: NASA Issues Press Statement About Propulsion System They Have Been Working On Since 1979
"We are researching it, and we think it will work," says top NASA spin-doctor, "although we will not be launching anything like this anytime soon. We are very excited about it, and the opportunities it will create."
This astounding news came on the heels of an earlier report from NASA (last year) when they said, "we are researching it, and we think it will work, although we will not be launching anything like this anytime soon. We are very excited about it, and the opportunities it will create."
When nothing happens again, we will be there.
Information wants to be anthropomorphized.
Isn't this the same kind of propulsion used by that experimental "deep space" probe that NASA launched last year? I sort of remember something going wrong with it...
I would think it'd take more effort to establish a self-sustaining base on the Moon than it would on Mars, given the limited resources to be found on the Moon.
But, the advantage to the Moon is the proximity to Earth - if things go wrong, its just a 3 day trip to the plentiful resources of Earth.
So, we refine the self-sustaining tech needed to live on Mars, using our own backyard lab (the Moon), and once that's all happening, send the tech off to Mars. Not to mention that we could probably *manufacture* half of the Mars base from the Moon, which would be cheaper and less dangerous than doing it here on Earth. Heck, we could probably use all sorts of crazy ass tech on the moon to build things better, such as nuclear technology, etc.
Seems sorta backwards to me that we're ignoring this resource and trying to get straight to Mars instead, but then again I don't know how these things are budgeted. Perhaps there are political reasons for getting th Mars before doing the Moon thing - and after all, politics drive the space program.
Reading the Zubrin book will answer a lot of these questions.
Basically, its cheaper to get to Mars than the Moon(read the book, most library systems seem to have it). And, Mars offers a lot more useful resources once you get there.
RE: No known material could withstand these temperatures.
So those "plasma globes" in Radio Shack really aren't?
And this particular plasma, wouldn't it melt the craft producing it?
--- Jump!! Fire!! Bullet time!! - Lego version of the Matrix
VASIMR - isn't that short for Vapid Americans Say Is Metric Required?
Or, in layman's terms, "Oh crap, they calculated it in inches even though the rest of the world put their contributions in in metric. Oh well, a few more billion dollars down the tube..."
Or "The mother of all fireworks..."
--- Jump!! Fire!! Bullet time!! - Lego version of the Matrix
You turn around before the half-way point - as long as thrust before and after the turn are roughly equal (taking into account gravity and other effects) you'll arrive just fine, just less time on boost vs deceleration.
You're no rocket scientist are you?
THE YEAR WAS 2081, and everybody was finally equal...
I have good news and bad news:
/. trollers and shitting potato-powered beowulf clusters.
The bad news is that the Martians have landed.
The good news is they're eating fanatical, conservative, off-topic,
OK, let's get the physics straight:
The Earth radiates more energy to space than it receives from the Sun. (The -- small -- extra energy comes from radioactive decay within the Earth.) We do not live off the energy from the Sun.
The difference is in the "quality" of the energy or, more precisely, it's entropy. The Sun is a much hotter object than the Earth; the entropy of the Sun's energy is therefore much less than the entropy of the energy when it is radiated from the Earth. (A system that receives the heat dQ (in a reversible process) increases its entropy by dS = dQ / T where T is the absolute temperature.)
The Earth therefore has a "negative entropy surplus" (talk about double negatives!).
Negative entropy means order. (A system's entropy is proportional to the logatithm of the number of states it can have. Less entropy is therefore fewer states or more order.)
Order means complex structures. Complex structures like life, like you and me.
You are right about the Universe dying the entropic death if it is expanding or flat (see my reference above), but not if it is contracting. But in any case we die. Somebody please figure out a way to create new universes before that happens.
IAAP.
Hi!
According to the web site it takes 30 days just to get out of orbit with this thruster. I don't think that, for short trips like the moon, that this is going to be useful.
Wake up - the future is arriving faster than you think.
Hmm, let's not.
Let's see, we can work on developing constant acceleration technology that makes travel time proportional to a logarithm of the distance, or we can keep screwing around with old burst acceleration technology (rockets) that makes time directly proportional to the distance.
Once we have the good constant acceleration engines, we could go anywhere we wanted in the solar system. The Pluto round trip takes only about 7 times as long as the Mars round trip (I assume simplified trajectories; real space travellers would use quicker ones). At a very reasonable 0.01 g, that means a month and a half for the Mars round, under a year for the Pluto round.
Or we could, as you say, just launch a damn ship NOW... and have another Apollo that leads nowhere. Woohoo! Another plastic flag and some footprints on a dead world for us to not visit for decades! That's something to get excited about, isn't it?
- You still need reaction mass, which you have to carry with you. Plasma propulsion just gives you better exhaust velocities, so you get more impulse for your reaction mass.
- What do they intend to use to power the thing? The classic plan is to use a nuclear reactor. This scares a lot of people, especially since this might require a rather large reactor. (Hydrogen fusion has often been suggested, but that doesn't work yet.)
- There's no indication that NASA is anywhere near building flight hardware, or even has an engine running on a static test stand.
It's a reasonable idea, but the PR piece is so uninformative that it looks like NASA turned somebody's annual progress report into a press release.Something has to ionise the gas, heat it, and power/control the electro-magnets that guide the plasma. How much power does this require? What's the source? How dense is it as an energy source (compared with the chemical rockets)?
I can see how some nasa propaganda artists are trying to sell this idea as a safety issue, describing how it reduces the risk of radiation Remember the gemini program? Since when did we start to care? Think about mir, thats sure as hell has been up a while. Man, they used to put guys in space for as long as they could afford it, just to see if they would get wiped out by space monsters.
-f
Friends don't let friends use multiple inheritance.
... given how most humans generally flock to any new technologies like flies to a fresh pile of p00, one can only imagine the world in the year 2100 and beyond.
With all our lovely "Magneto-Plaz LE" personal transportation units flying through the now-charted solar system, and perhaps beyond, the interplanetary traffic jams, and a new form of commuter anger known as "Solar Flare".
That's when all of the sudden, The Powers That Be(tm) announce that all the magnetics from the units are producing a new type of pollution that is quickly destroying the natural magnetospheres of the planets and moons, and that earth is on a direct collision course for Mars.
Today will be the day they look back on as the catalyst for the destruction of the world, but hey, who doesn't want to fly a spacecraft?
I don't know anything much about such things, but doesn't it seem relatively realistic that something like this could happen? Can large amounts of foreign (manmade) magnets disrupt planetary magnetics?
your mass would be dropping...
DNA just wants to be free...
Well, to heat all this plasma, we certainly need a nuclear reactor. But more importantly, this is hydrogen plasma. And all that hydrogen needs to come from somewhere. That can mean only one thing...
Bussard collecters!
Yes! Even more life-imitates-[Larry Niven | Star Trek]!
I think I'll go lie down now...
===
-J
Karma: T-rexcellent.
Launch costs from the earths surface are about $8000/lb right now. But there's plenty of stuff already up there that you can use for reaction mass, once you get there.
Minimising reaction mass isn't the problem. That isn't the bottleneck to getting to Mars. Finance is the bottleneck. Missions to Mars require maybe 100 tonnes launched to get there. You do the math.
If we use asteroid mass to build our hardware, the costs drop by several orders of magnitude. Going straight to Mars ain't gonna happen in my opinion.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"A Bugg
I'm glad you mentioned that. You know I get so sick of listening to people piss and moan about hazardous waste, be it chemical or nuclear or whatever. Make as much of the stuff as you want, we will be able to get rid of it in the forseeable future.
I'm just not willing to believe that in the next 100 years we won't be able to make rockets that are 99.999% reliable, and relatively cheap to send up. So, take it as a given that in 2100 we will be able to send the stuff up for reasonable dollar amounts with a reasonable amount of risk. In that case, store the stuff on a 100 acre lot in some desert somewhere.
Casca
For constant acceleration, travel time is proportional to the square root of the distance. I don't know why I mentioned logarithms (except, perhaps, that it's more fun to say than "square root").
a) the total amount of metal in one asteroid, Eros is greater than the entire mineable surface of the earth. And there are probably millions of asteroids where that came from...
b) solar energy is an unlimited source of energy, which is available 24x7 in orbit and is relatively easy to tap.
c) the actual, real underlying cost of putting a man into orbit is similar to the cost of crossing the atlantic (it sounds nutty, but the cost of rockets is completely dominated by building each one by hand and then throwing it away afterwards, it's a bit like building a 767 and then trashing it after one flight; the fuel cost is only a few tens of dollars per pound)
d) there's plenty of water and carbon up there- where do you think the earth got its carbon from? It condensed out of the body of a supernova.. as did the asteroids.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"This is just a thought, and some random ramblings, but what about if you launch this thing from lunar orbit?
First of all, although only a dozen people ever got to walk on the moon, there were another dozen who at least got to orbit the moon (including preparatory missions like Apollo 8 & 10 as well as the command module pilots) This way you are outside of the Van Allen Belts, but still close enough to home that other vehicles could get you to your "spacecraft" without having to burn fuel to get there in the first place.
In many ways it is too bad that the Jupiter rocket was never built (that was to follow the Saturn V... and talk about a monster rocket!) One of the early proposals was to send people to the moon by building a large earth-orbiting space station and then sending the moon craft directly from a docking bay of a space station. Von Braun pushed for the method eventually used (with a direct take-off from the ground, and everything brought with them). Had the orbiting station been built (for admittedly more money), at least there would have been an established infrastructure to build upon for future missions.
Unforunately all we got out of all the money spent by NASA for a space infrastructure is Kennedy Space Center (which still is an accomplishment) and a bunch of souviners scattered over Australia when Skylab came crashing down. Oh, and I can't forget the 5 space shuttles. Wow! What a marvelous space infrastructure to really go places!
I think the main argument for going to Mars rather than the Moon is that Mars is far more likely to have significant amounts of water.
If you post it, they will read.
If you're going to wish for a new technology to be "flawless and is able to be implemented in a cost effective manner" without going through the intermediate research steps, then also wish for a pony.
One makes as much about sense as the other.
Sorry if this sounds like a flame, but it's important to make the point: Ya gotta invest in the research to get the final product. (And, typically learn a whole lot on the way, giving rise to new technologies undreamt of earlier.)
NASA gets around half a percent of the US Federal budget. We need more research like this, and some of the most promising ideas need to be tested as part of the Deep Space series of engineering test beds. I'd rather have my tax money used for these purposes than the usual government boondoggles.
--
"You've crossed my Line of Death!" "What? No! Where is it?" "Here in the fine print...."
For constant accleration, zero initial speed:
d = (at^2)/2
t = sqrt(2d/a)
a = 2d/t^2
d = 2.8 x 10^10 m (halfway)
t = 45 days (halfway)
t = 45*24*60*60 s
t = 3.8 x 10^6 s
t^2 = 1.5 x 10^13 s^2
a = 2.8 x 10^10 m / 1.5 x 10^13 s^2
a = 0.004 m/s^2
or roughly 0.0004 g, with your assumptions.
At 1.3*g, it would take about two days.
I don't follow your logic.
It's desirable to reduce the mission time no matter WHERE the masses are coming from, for human reasons.
Why is it only beneficial if it saves us money?
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
last to calc lines should read:
a = 2 * 2.8 x 10^10 m / 1.5 x 10^13 s^2
a = 0.004 m/s^2
After looking at the sci amer article, did anyone else notice this thing is gonna be pumping out a lot of RF?
What an interesting way to be able to track a space craft! presumably you would be able to tell how well the engine is running by 'listening' to the 'sounds' it makes?
How cool!
Feldgercarb! (sp?) You've been watching Independence Day too much. That Malthusian view of resources is as dead as Bret Spinner after the alien got him. 8-)
99.9999999% of all the iron, manganese, aluminum, zinc, silver, gold, etc., that the human race has ever mined is still on the planet, just redistributed a bit. How is it gobbled up and gone? Heck, our landfills are richer in some elements that the projected low-grade ores that will be mined around 40 years from now. When that happens, expect the dumps to be run through a refinery. Recycling at last! ;^)
--
"You've crossed my Line of Death!" "What? No! Where is it?" "Here in the fine print...."
Screw Mars, I saw we start by colonizing the moon, then build on of those huge electro-magnetic launcher things (they've been in numerous movies) so we can propel objects even further in to space with less fuel.
That's my thoughts on that matter.
Field studies dating a number of volcanos in the three states has supported this idea. The farther west you go along the Snake River plateau, the older the volcanos get. The oldest ones in Oregon butt up against the Columbia Flood basalts. Anything older was buried under the unbelievably huge number of cubic miles of lava that flowed over most of Oregon, etc.
For a easily readable review of this evidence and more -- a rather controversial theory that tries to tie together several major features of the US West, see Roadside Geology of Idaho by David Alt and Donald W. Hyndman, ISBN: 0878422196. I don't necessarily buy Alt's and Hyndman's hypothesis, but it's a cool one to think about.
The same two authors have written other books in the "Roadside Geology" series, Montana, Oregon, Northern and Central California, and Washington.
Roadside Geology of Wyoming was written by Darwin R. Spearing and David R. Lageson (ISBN: 0878422161). It may not have the quirky unifying hypothesies found in the introductary chapters of the other books, but can't help but cover the hot-spot theory of Yellowstone's formation.
PS: I'm only mentioning the Roadside Geology book series as a satisfied customer. The books give a nice, casual overview of the respective states' geologies, sorted by major highways. Each book tells you what you're seeing out the windshield as you drive through the West.
--
"You've crossed my Line of Death!" "What? No! Where is it?" "Here in the fine print...."
Ok, let's say the first prototypes are fired in 2005, the first test launch in 2009, and the first unmanned vehicle launch in 2011. We will be loking at the mars mission starting to be blueprinted (the vehicle) in 2010. This will give us a launch date very close to the 2020 date. Now, if they keepresearching the hydroponics, air-rebreather systems, and water re-circ systems along with the composites we dang well could have a good chance of getting a mission there and back! I can see a mission similar to apollo except instead of landing your habitat when you arive, having it already on the ground...
Hmmm, can we actually pull this off? or will we just bitch and moan about gas prices,taxes, etc... and have our bloated, corrupt, and useless senators and represenatives erase NASA and the space program because it doesn't line their pockets..
Call or write your senator and tell him how important the space program really is and how it needs to have it's funding increased!
Do not look at laser with remaining good eye.
YES! Now it will take only half as long to crash a $150 million probe into Mars! This is a real breakthrough! We can disperse twice as much debris on the Martian surface in the same amount of time!
Lenny
ByteMyCode.com: A Web 2.0 code sharing community.
Even if getting the mass gives a net income rather than a net loss?
Even if the resulting commerce results in permanent, sustainable space habitation, rather than the one shot throw-away-Apollo style mars mission?
Even if asteroid mining reduces the cost of your cars catalytic converter?
Even if asteroid mining decreases the chance of earth dying from a meteorite?
Because that's really what's at stake. Mars looks like there's certainly stuff there that is good to get, but there's lots more other stuff elsewhere that is better, easier and cheaper, and will help us get to mars for a fraction the cost and with incredibly more style.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"I'm not AGAINST asteroid mining.
What I'm asking you is why the plasma drive isn't useful today, not why we should or shouldn't mine asteroids. I already know why we should be doing mining and fabrication in orbit rather than planetside.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The way the planet works, all resources cycle.
True. They cycle...
A simplistic example is water. When you use it up, it cycles back around and is regenerated.
Not true. They don't all recycle. They go from the state of matter to energy. For example, we incinerate many thousands of millions of tons of household and industrial waste every year - leaving some ash to sprinkle on a road and heat.
We don't yet have the ability to convert energy (heat or any other kind) into matter.
We have to get more raw materials.
This sig left unintentionally blank.
Let's start the cold war all over again. Come on, it'll be fun.
My mom is not a Karma whore!
They're not doing it to large amounts of hydrogen at a time. A regular RTG should suffice.
"If one is really a superior person, the fact is likely to leak out without too much assistance" -- John Andrew Holmes
"Mommy, I have to pee... can we stop so I can go potty?? " :^)
Ender
Nothing to see here
"I'm not saying it's for better or worse, but the fact that this propulsion system would mean launching large amounts of plutonium atop a chemical rocket to get out of the Earth's gravity well shouldn't be overlooked or swept under the rug. The potential for disaster is there. "
I completely disagree with you about the potential safety hazards of nuclear power supplies in space craft. However, there are alternatives to using nuclear materials to power a plasma rocket. Most involve a variant of solar power. Some represent a much better power supply solution for a plasma drive than does a radio-isotopic power supply. Each has its own unique advantages and disadvantages:
- Photovotaic
- Solar Thermal Generator
- Photovoltaic/Solar Thermal hybrid
- Microwave Power Transmission
- Solar Thermal/Isotopic hybrid
- Photovoltaic/Solar Thermal/Iostopic hybrid
1. Photovotaic (PV): "That durn thing looks like a christmas tree!"
Advantages: high reliability, graceful failure modes, low complexity, a significant amount of in-space experience with the technology.
Disadvantages: medium to high mass, low power to mass ratio, high launch & on-orbit assembly costs, low power conversion efficiency, efficiency degrades over time.
PV panels can be hung along boom arms on the ship. Assuming a 25% conversion efficiency of sunlight to power, then a square meter of PV panel will generate about 342 (1370 * 25%) watts near Earth and about 147 (590 * 25%) watts near Mars. Assuming the spaceship needs about 20 kw of continuous power when the engines are on, then the ship would need a minimum of 136 sq-m (1464 sq-ft, for the metric impaired) of PV panels. If 200 sq-m (2153 sq-ft) of panels were used, then the panels could lose up to 32% of their efficiency or area before effecting the trip. Thin film, flexible PV panels are already in use in space today.
2. Solar Thermal Generator (STG): "Hey, that thing looks like my Pappy's old satellite dish. Wonder if he gets free cable?"
Advantages: high power to mass ratio, variable power generation, high power levels.
Disadvantages: medium complexity, several point-failure modes, little or no experience with technology in-orbit.
Basically we set up a big concentrating mirror, heat a working fluid, then spin a turbine to generate electricity. An inflatable mirror or mylar Freznel reflector could be used to concentrate the sunlight. Either could be compactly stored for launch from Earth and deployed in orbit. Energy conversion efficiencies of 60%-70% are easily achievable. Assuming again that about 20 kw of continuous power would be needed and that the STG has a conversion efficiency of 60%, then the concentrator would need to have an area of approximately 57 sq-m (613 sq-ft). If the concentrator is a flat mylar freznel lens, then its diameter is only 4.26 meters (14 feet)! This makes the STG collection surface about one quarter the area of an equivalent PV system. The turbine could be replaced with a higher efficiency Sterling Engine, or even a direct thermal conversion system as is used in some thermal-isotopic (eg the dreaded nuke!) systems. The amount of power generated can be varied by moving the heating chamber away/toward the focal point.
3. Photovoltaic/Solar Thermal hybrid (P/STG): "Still looks like my Pappy's old satellite dish."
Advantages: Same as for STG, higher conversion efficiency, lower mass, high power to mass ratio.
Disadvantages: Same as for STG, high complexity, higher chance of system degradation/failure.
This is basically an STG with a small PV pasted on the front of the heating chamber. The PV is cooled by the working fluid in the heating chamber. The heated fluid then goes on to the turbine, just like in a regular STG. The PV is there to extract just a bit more power than the STG alone can manage. The down side is that the PV must be kept cool by the working fluid. This makes designing both the PV and the heat exchanger a challenge. If the PV fries, then it could degrade the system to the point that it is LESS efficient than an unassisted STG would be. The payoff is that you can get 90%+ energy conversion efficiencies with this gadget.
4. Microwave Power Transmission (MPT): "We went wireless, because we ran out of extension cords."
Advantages: High power to mass ratio, very high reliability, power source easy to maintain (transmitter near Earth), its really nifty.
Disadvantages: Precision pointing needed for transmitting antenna, very low total system efficiency.
Take our STG, put it in L5 on a space station or somesuch. The STG powers a big maser ("microwave amplification by stimulated emission of radiation", it was invented before the laser) which transmits power to the ship. The ship sits in the center of HUGE, but low-mass spiderweb of antenna wires. The wires lead straight into a solid state tuner/power converter. An MPT could conceiveably shave tons off of spacecraft's total mass. Another big advantage is that the power generating component of the "engine" is left back near Earth where it can be more easily maintained and repaired. The disadvantages are that the power beam must be aimed and shaped with a very high degree of precision. If it is off by a fraction of an arc-second, then the ship loses power. Please note that the microwave power levels would not be high enough to heat water, much less fry the ship or anyone inside it. The beam would be spead out over a multi-kilometer radius. This scheme is unlikely to be used, but is one of the cooler ideas for supplying power to a spaceship.
5. Solar Thermal/Isotopic hybrid (ST/IH): "Hey, why is that guy's satellite dish glowing?"
Advantages: All the advantages of an STG, minimal power available when collector not deployed or disabled.
Disadvantages: All the disadvantages of an STG, higher system complexity, people have an irrational fear of anything "nuclear".
Again take our ubiquitous STG, now we supplement it with a safely designed radio-isotopic heater (you pick the radioactive). It acts as a supplemental heating stage for the STG. Besides reducing the concentrator size, it also allows the ship to generate power when the STG is not or cannot operate. This represents a huge increase in safety for the crew of our intrepid, but hypothetical, Mars ship. They can bring the STG down for repairs inflight if needed and not have to worry about running out of reserve battery power. While an ST/IH power system is a really good idea, it will probably never happen. Too many people are scared spitless of anything that says "nuclear" pinned on it.
6. Photovoltaic/Solar Thermal/Iostopic hybrid: "What the heck IS that thing? Its scaring the children."
Advantages: All
Disadvantages: All
Ok, so I made this one up. I just took most of the ideas above and rolled them all together into one big mess. Really it is just our ST/IH system with a PV pasted on the front of the heating chamber again. This one is brought to you by the Dept. of Redundancy Deptartment.
That's enough for now.
IV
"These laws they're passing won't even compile anymore, let alone execute." - anon
The October Sky "rocket boy" Homer Hickam is researching the prospects of antimatter rockets. This technology is predicted to be 100 times more efficient than chemical rockets, and a journey to Mars could be done in "weeks". I read about a lecture he gave where he said that with the right funding, we could see antimatter rockets in ten years. He said they got the first shipment of antimatter to his lab something like a year ago. Here is a related article in ABC News.
Donate background CPU time to fight cancer.
Someone please let me in on the secret!
Not quite, Mars' atmosphere contains 0.03% water, which can be electrolyzed to release hydrogen. Some of the Viking lander pictures showed a dusting of frost on the nearby rocks. So, there is "some evidence" of hydrogen. It's possible that a fuel processing plant at one of Mars' polar caps could steam quite a lot of water out of the dust/ice/dry ice terraces there.
However, you are right in another sense. Zubrin and company, in planning Mars Direct, didn't want to rely on the traces of atmospheric water, or the chancy terrain around the poles. So, he proposed carrying the hydrogen to Mars, at least for the first few missions.
That's a pain. It's extra mass to carry, and LH2 needs large tanks as it is not very dense. Keeping it liquid for the duration of a trip to Mars requires refrigeration. If there were a rich, guaranteed source of hydrogen compounds on Mars, the cost of Mars Direct could be reduced even further.
Another possible source of hydrogen in the Mars system are its moons: Phobos and Deimos. The Soviet probe Phobos 2 found that Phobos was outgassing some volatile or another, but failed before it had identified the substance. Both moons have the surface spectra of C-type asteroids, but without the chemically bound water, and are less dense than ordinary rock. The odds are that while the surface may have been baked free of water, their interiors might contain a fair amount of ice and/or other carbon/hydrogen compounds. (See the chemistry of the carbonaceous chondrite meteorites for details.)
So, Phobos was probably outgassing water vapor, or maybe hydrogen cracked from the water by solar UV light.
A manned mission to either or both of those moons would be a good idea. After a small investment, they might turn out to be filling stations in space, handy for spacecraft returning to Earth.
--
"You've crossed my Line of Death!" "What? No! Where is it?" "Here in the fine print...."
Dan Goldin has stated that the maned Mars mission can only happen after a way to repair damaged cells is developed. Am I to understand that this plasma propulsion reduces the travel time so much that cell damage is no longer a significant risk? I guess my point is, Mars is still a long ways off and I'd hate to see other projects sap money from repairing damaged cells. Realistically, I believe investment in cell repair will offer more benefits to us all than investment in plasma propulsion. The best solution would be to give NASA enough funding for both, but I never hold my breath waiting for kongress to come up with the best solution.
"I can only show you Linux... you're the one who has to read the man pages."
Plasma is faster. An ICBM using plasma propulsion will go little over twice the speed of the conventional ICBM. The plasma rocket will be able to avoid any anti-missiles, while the regular rocket won't.
But then again, build a better mousetrap...
Chris 'coldacid' Charabaruk Meldstar Entertainment
The one that caught my eye is an parachute like system, where the ship moves with the energy emmited by the sun, and it accelerates constantly and in 1 year going at 10% the speed of light!
Altough to reach that speed it will need to have the sun following it, and that can't be used.
--
EHC
Like many vehicle, a spaceship's cost stem in a large part from life support and security systems. Developping a reasonably safe vehicle to carry humans will take time because we want to limit the risks incured to human life. And we need a fast ship also because of the limitations of humans. Cargo does not require as much care and so much constraints. So while we are busy developping human transport, why not preposition cargo ? Prepositionned materials and equipment in orbit and on Mars surface would just wait for personnel to arrive and find ressources and support not as scarce as if they had been limited to what they brought in with them. Nothing revolutionnary yet (orbital castles and other concepts have already mentionned that idea), but my suggestion would be to push it further : the space industry is at an artisanal stage, and this is what drives costs up. Mass producing and prepositionning standardized automated one-way cargo ships would enable favorable conditions for a future human mission at a much lower cost. The critical path in this project is the human part, but once it is possible, we can avoid further delay by being ready at the right time.
Correct me if I'm wrong (IANAS), but this thing basically ionises hydrogen, then heats the hydrogen ions until it becomes plasma, and then spits it out. A real nice exhaust of positively charged matter. But aren't you then amassing surplus electrons in the hull? It would sure generate a real nice spark upon entering the Mars atmosphere :)
)O(
the Gods have a sense of humour,
Never underestimate the power of stupidity
To err is human, to moo bovine
Here.
--
Peter
Did you actually read any Einstein? The theory of uniformly moving reference systems is called the "theory of special relativity".
Travel times are relative. You can accelerate as long as you want, you get faster and faster and your total travel time goes down accordingly. It's just that the rest of the universe starts to behave "strangely" as you approach relative speeds close to c. But that does not affect the travellers ability to accelerate. At high relative velocities, you don't decrease your travel time by increasing the relative speed but by compressing space in the direction of your motion. There is just less distance to cover! If you could accelerate with one 1 g indefinitely, each year your subjective "speed" would increase by approximately the speed of light. After 10 years of acceleration you make 10 light years (from earth's point of view) in one year! (your idea of a year, that is)
If you intend to come back to earth, it's a different story, though. Here, people will think that you accelerated well up to a certain point when you started getting close to c. From then on your acceleration was decreasing asymptotically, so that you actually took an awful long time to complete the journey. It's all relative, isn't it?
Except that in space you cannot just travel in a straight line. The Sun and other large bodies will pull you into an orbit. So the distance to travel is much longer than the actual distance betwene the two planets
You may have taken this into account in your calc, but you dont mention it. Your answer seems very wrong though 50000kmh isnt all that much apollo did 29000 or something like that. And that was only from earth to moon. Id expect a month of acceleration getting you up to a bit more speed than this. Fighter planes does 0-1000 in seconds in AIR
In addtion, you just cannot go ahead and fire up your spaceship any day of the week. You have to wait for a "window". This has got something to do with Gravity too. For conventinal "space ships" this window is about every 6 months or so
Dont know about plasma crafts
-- damn, it seemed so easy in star wars
People don't realize that NASA isn't going to just launch a plasma based ship directly from earth. That would be too costly and could cause some problems. Instead, the chain of events most likely be a three tier journey, starting off with a stop at the space station orbiting earth for supplies, than again at a base on the moon for more supplies. Albeit this is all hypothetical since we have no base on the moon (or for that matter an actual full fledged space station yet). There are many hurdles to overcome before we can attempt a mission to mars....I sure hope that I am still alive to see it (or manned deep space exploration for that matter - which could happen if trends in technology continue). Just my $.02....
Here's the clincher: a faster engine will not make any significant difference. A few posts have noted some of the important aspects of a successful mission -- weight, supplies, etc. Other important aspects are setting yourself up for the right return window, and for an acceptable hierarchy of safe bail-out options.
The optimal launch scenario is when Mars and Earth are in conjunction alignment -- on opposite sides of the sun. At a speed of around 3km/s everything lines up very nicely, and these speeds can be attained using plain old 60's Saturn V launch platforms, or some modern-day equivalent (NASA has many such designs; for example, some based on alternate clusterings of shuttle boosters).
This launch configuration carries a fixed time-to-Mars of about 180-240 days. Going any faster would just complicate the issue (and eventually cause you to miss your target, which would pretty clearly be A Bad Thing.)
Obviously since Dr. Zubrin wrote a whole book the subject I can't get too detailed here, but if this topic interests you, GET THIS BOOK. Hell, the hardcover is only $17 and I think the softcover was something like $11. Most of us IT guys have made that much jack just browsing /. today...
The book rules, it's very interesting and informative, and it will piss you off that we aren't 75% there already. However, it's better to be pissed off and well-informed than techno-dazzled and blithely assuming NASA is spending wisely, which is what I personally suspect is behind a lot of these enthusiastic "KEWL" replies...
Slashdot quality declines as the number of hot grits posts decreases. - Provolt's Law, Apr-09-2005
...until a more efficient means of getting payload into orbit is developed. The last time I read up on this technology the info given made it clear that this propulsion was useless inside a gravity well. Until we can get to the point where the cost for payload launched into orbit costs hundreds of dollars per pound (or less)instead of thousands of dollars this is academic.
We need what has been envisioned but not delivered for the last 30 years, namely the "space bus". The shuttle was initially supposed to be a first step in this direction: a cheap, efficient, reusable means of getting cargo and people into orbit. Once we have some type of vehicle that doesn't require tons of solid/liquid fuel at enormous cost and risk to reach orbit then the moon, mars or even farther destinations are much more likely to be reached within the next 20 years.
Also, on the environmentalist side of things; from what I understand of most of the arguments made by environmentalists against nukes in the space program are it's the launching of nuclear material and not the use in space that they are against. If the worst should happen and NASA loses a nuclear payload in near earth vicinity the fallout could be devastating. Once you're actually in "space" (ie - beyond earth's magnetic field) radiation is pretty much all that there is! Spacecraft will have to be designed with heavy shielding in mind for a mars trip, otherwise one solar flare could conceivably endanger an entire mission.
*lol* My question is how do you pull over for those kids that always have to go to the bathroom every few miles? No, seriously. It's amazing what we can do with technology, but let's hope that we can properly use this for the good of humanity. Mankind has this knack for taking good things and making a "whoops".
**Do not meddle in the affairs of Dragons, as you are crunchy and taste good with ketchup**
Seriously, advanced propulsion technologies like this are going to be responsible for putting mankind in the position to be able to really explore the solarsystem. But this should not be done too quickly.
The space programs of the United States and Russia have mostly been used for short-term, near-sighted political purposes. [The space shuttle being an exception] It's about time that the use of space programs grew-up a little. In that light, it is good to see this effort to develop better technology rather than just throwing something together with the technology at hand.
Honestly, we can't go to Mars or even the Moon that well with the existing propulsion systems. How much of the Saturn V rocket actually returned to Earth? Just the tiny Command Module. The rest of the rocket carried the LEM, The Service Module, but mainly it was fuel to power the conventional engines. We can't keep doing that. That's like sending out Columbus with his large ships and all that can make it back are row-boats.
Technologies like the X-33, Plasma engines, and a practical, perminent space station are what we need to explore. A reusable, self-contained ship that can take of from the surface of a planet and go straight into orbit that can dock with a space station wich can dock with a large inter-planetary transport, which could take the resuable ship to the Moon, Mars, or where ever. A perminent, well thought out set up like this could be more than enough to allow for exploration, let alone commercial ventures.
The real question I have is: Do we have the wisdom to make real, long-term plans for this technology?
The article mentions that the ship would require around 10 MW of electrical power for the drive.
I wonder how they're going to generate that, given that a thermal solar power source as proposed in Encounter with Tiber is only about 1 MW, and that the best solar panels were about 12% efficient last time I checked.
To generate 10 MW photovoltaically, you'd need about 62000 square meters of solar panels. (assuming solar irradiation is 1300 W/m^2, and an efficiency of 12%) That's a rectangle about 250 meters square!
I wonder what a nuclear reactor of this power would weigh?
Does anybody know how this drive compares to the drives built in the NERVA (using a fission pile to heat has directly) project with regard to thrust and specific impulse?
Never ascribe to malice that which is adequately explained by incompetence.
... ordered the Zubrin book, will read it this week.
Thanks for the reference meloneg!
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --