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Going To Space Inside Magnetic Bubbles
Ecyrd writes: "Those fine guys at NASA have figured out a way to hitch rides to space inside magnetic bubbles, creating both an efficient propulsion system and protection from high-energy particles. Sorta taking the Earth's magnetosphere with you as a protective cloak when you go." The propulsion in this case comes not from within, but by using the magnetic bubble as a giant solar sail.
How the hell do you make it slow down? Even if you never touched an atmosphere, you'd still need big, bulky engines to slow down so you don't splat yourself into wherever it is you're going. And it may deflect solar flares, but it damn sure isn't going to deflect a head-on collusion with anythign solid.
No, you can't tack. Tacking with a sailboat uses the force of the water to keep it bouyant and at an angle. In space you don't have that force because its space. The only way you could "tack" is if you have thrust. In that case, you might as well not use a magnetic field since it would be an opposing force. The thrust you would need to generate to tack would produce an unoptimal usage of resources to get where you wanted to go.
As for using an "unbalanced" magenetic field, well that would just cause you to spin and move in the direction of the wind.
The sun can't be the only thing out there exerting solar wind. Even so, though, how would you get back home? Or how do you even slow down?
...
They may be going for a trial in 2001, but there was no mention at all of getting back to earth, or even slowing down (or steering!) mentioned in the article at all
Anyone every read H.G. Wells...The First Men in the Moon? I'll bet he is rolling in his grave right now...
I don't want to go backward in life, I want to go forward! To hell with reverse...
/.2... it will be beautiful... and we all know trolls can't survive in the vacuum of space.
/.... farewell
Especially with the quality of posts (noting this one as a prime example)... I'm on the next Magno-Bubble off this hunk of dirt. I'll realize my dream of starting Internet2 and
It was great while it lasted, but better get while the getting is good. Farewell
"You should always go to other people's funerals; otherwise, they won't come to yours." -- Yogi Berra
read the rest of the thread.
Slashdot, would a spell-checker for posting be too much to ask? It's not rocket science!
The latest study shows that worrying about magnetic fields causing cancer causes cancer.
-Pete
Yeah? What about the three months to get to that speed?
-Pete
I can imagine a Pooh-Bear of the future inside of his magneto bubble, covered with mud, singing, "I'm just a little black space cloud hovering over the honey tree. . ."
Its so simple...just reverse the polarity of the magnet. The Sun would then pull the bubble, rather than push it.
The only thing we have to fear...
is all that really frightening stuff
this idea rules! just send some sort of magneto bubble/thruster package with drilling capabilities into space, point it in the right direction, and stick it to an asteroid in it's path. 10 years later, asteroid arrives at earth, vallet style. then mine out the asteroid in a honeycomb fashon, tether a cold fusion generator to the asteroid, and heat the inside and rent it out as some bitchin' penthouses. with views.
moox. for a new generation.
i would assume they'd speed up going twords a body, and then slingshot around it using the gravitational force to sling them back to earth, or their original origin while keeping the magneto bubble deflated
moox. for a new generation.
This isn't so bizarre. Science fiction writers have been clinging to this concept for a long, long time. (At least, the concept of riding on mangnetic waves).
My personal favorite is Dan Simmons' vision of the Ousters with multi-kilometer wings that could 'catch the magnetic waves' and push them around in space. Like giant butterflies. Very cool. It's nice to see another of the science fiction authors' predictions coming true.
Bite my yammer.
Before you get carried away by "That's enough to accelerate a 200 kg spacecraft from a dead stop to 80 km/s (180,000 mph) in only 3 months.", remember that just 2 astronauts and their suits are heavier than that. That's without any actual spaceship.
Also later on it says
Maintaining such a bubble in space would require about 1 kW of power and less than 1 kg per day of helium propellant for the plasma source. In return, the bubble would intercept about 600 kW of solar wind power.
So... if it weighs 200 kg, and uses 1 kg per day for propellant... Isn't there a fundamental problem here...?
mass expended per unit time is a rate.
This is a guess, but I'm pretty sure that I'm right: The magnetic field does not get more intense, it gets larger: the gas blows it up like a balloon. I would assume that the per-unit-area intensity decreases as the size increases, which means that, for a given field power, there would be an upper limit on field size: at some point, the field will become so large (and thus so weak) that the gas leaks out faster than you can replace it.
"Research is what I am doing when I don't know what I am doing." -- Wernher von Braun
Wouldn't the force of accelerating that fast kill a person?
I guess we can forget taking one of these things ourselves anywhere.
That star would have a solar wind itslef, would it not?
I think the more important thing is running into a planet or asteroid.
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ADVENTURERS! - ANTIHERO FOR HIRE - CARDMASTER CONFLICT
Good question. Whats even cooler though is how they can use the same propulsion system to stop. If they're traveling towards another star, they can gradually reduce the field in such a way that it'd bring them to a stop in just the right place. If the field was too strong, then they'd stop somewhere a little further than halfway, and if it wasn't strong enough, then they'd never stop.
There is no such thing as a frictionless anything. even in space there is dust, radiation, and all kinds of other things that WILL slow you down. And what i was trying to say is that had best not be off target or you will be missing your ride home. you would have to be at another star to get your push back, but if you miss a star then your SOL.
You speak of 'just travelling in space' as though that really wasn't much of a breakthrough at all! Granted, this is not the technology that will send the Millenium Falcon roaring out of Mos Eisley. It's not supposed to be. In a way, this technology is more exciting than that. This technology makes the idea of a manned trip to Jupiter, etc. much more of a possibility. We can get (roaring, even) into space already, albeit clumsily. Where we go from there and how we survive while doing so is where things get really sticky. This is great news!
**>>BELCH
That occured to me also. Either you use this kind of thing on a one-way trip (good for expendable probes) or you make a sling-shot around the planet of interest and conduct your business *real fast* on the fly-by. ;) I haven't heard anything written on the concept of "tacking" upwind like you would do in a sailboat (since I believe that makes use of lateral pressure exerted on the boat from the water). The only thing left would be some other (more conventional?) thrust device, but now we're stacking up lots of extra mass to the point that the magnetic sail wouldn't work nearly as well to begin with, rending the discussion somewhat moot.
Unrelated to this, though, I have to wonder how massive the magnetic generator itself is. Sounds like they can meet the 1kW power requirement well enough, but it needs [nearly] 1kg of "fuel" (for plasma) also per day. The numbers quoted at the top for a 200kg vehicle isn't all the heavy. By the time you add yourself, a friend, and the obligatory Beowolf/Linux cluster, well, I just start wondering if it would truly attain their listed speed *or* endurance rating. Just my thoughts.
cancel the supply mission?
Intolerant people should be shot.
With more time to think, "tacking" certainly wasn't the right word to use, as this means progress upwind.
I'm really thinking more of steering. The solar wind will always be radially outward from the sun. I'm thinking in terms of gaining accelleration in the plain perpendicular to the local wind vector.
THe force vector will be radially outward. To knock off a dimension, assume that we stay in the plane of the solor system. If the vessel is off of the vector, displaced by an angle theta (where 0 would be on the vector), the accelleration breaks into Fcos(theta) away from the sun, and Fsin(theta) laterally.
As far as the filed, I don't mean making the field funny, but instead to spread out the unit in some way so that the field is generated away from the center of gravity of the entire vessel. This should give a similar ability to move outward.
There would still always be accelleration outward. HOwever, if it is possible to move the vessel far enough off center, it may be possible to move outward while accellerating against the direction of orbit, enough so that the orbit decays and the craft comes inward under the force of gravity.
hawk, who could have done the math for this in his sleep 15 years ago . . .
As far as I can tell, this has nothing to do with going to space. It's talking about once you're already there. Isn't accelerating 200kg to 180,000mph in 3 months a little low to actually break out of earth's gravity? Unless they are referring to hitching a ride on the magnetosphere. But they never actually said anything about leaving earth on one of these, just travelling in space.
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you may quote me
I wouldn't mind seeing the comparison between rocket propulsion and electromagnetic propulsion (incluing ramjets, ion, etc)...based on cost, efficiency, speed and payload capability. The rockets seem to be able to carry larger amounts of weight, but they only go so far. Ion propulsion, takes less money and less full, but takes little bit longer. However, it can go faster and longer easier. (hence deep space missions). What is the use for this new technology? Obervation missions only or a long-span manned flight? I suppose I could research it more...but if it is anything like my electrostatic paper research...it is too much info :)
-Corey
Quick question (maybe a stupid one)...
Does this miniature magnetosphere have to be turned off everytime you need to talk to your craft?
It would seem to me it might interfere a tad with radio communications...
Man, what a nifty idea. Especially if the term "solar sail" conjures up for you images of kilometer-sized sheets of gold foil.
One thing I wished the article would have explained better: How is it that plasma can expand a magnetic field in that way? I mean, I see how you could block an EM field-- we see that everyday-- but intensify it? (without increasing the coil voltage, at that). Could anyone comment?
iSKUNK!
Oh wgere can I find the tic in tape??? please somebody tell me. I NEED to know. I might die...
You'd be sending equipment, not people. On the other hand, the 1kg/day propellant is a much more serious problem. It's probably not steerable enough to do a good flyby of one of the outer gas planets or their moons to pickup some hydrogen without risking falling into their gravity well. But you can find some interesting balance of weights and propulsion strengths to get out to interesting parts of space and send telemetry back, and once you're going that fast, it's a nice cruising speed.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
At first I read this and thought that it would be the greatest invention in the history of mankind, but then the skeptic in me hinted at the mathematician in me, and so they got together and did a few calculations. First of all, to say that a man-carrying spacecraft will weigh a mere 200 newtons is horribly unrealistic. Let's say it has a meager crew of two men, weighing 75 kg a piece, for a total of 150 kg; plus we'll say another 50 kg for spacesuits and such. Now we will use another 200 kg for the weight of the extremely diminutive spacecraft they are to travel in, all in all, that gives us a weight of 400 kg. However, for each day in flight, the engine requires 1 kg of fuel, and the astronauts, we will say, a conservative 3 kg of food a day, for another 4 kg of mass for each day of travel. It is approximately 5.8 billion km from pluto to the sun, and approximately 149 million km from the earth to the sun, so I hopefully can assume it is about 5.7 billion km from the earth to pluto, which I will use to represent the edge of the solar system (hey, it is, after all, isn't it?) Since F=ma and d=(at^2)/2, we can express d as being equal to (Ft^2)/(2m). There are about 86400 seconds in a day (slightly less, since a day is 23 hr, 56 min, 4.0989 s, but i have to be reasonable). The craft will need an extra 4 kg a day, which translates into 1 kg every 21600. We can then express the craft's mass in terms of t in s as m=400 kg+(t/21600s) kg. Using a bit of algebra we can get m=(Ft^2)/(2d). We can set these two equations equal to eachother and get the quadratic t^2-(1.75926*10^8)ts-(1.52*10^15)s^2=0. Solving this and eliminating a negative answer gives us about t=184 million seconds, or 2131 days, which is about 5.84 years. This would be far and away the longest mission ever (with an actual purpose, not including Russian guys spinning chess pieces in antigravity for ten years at a time while the government scrounges up enough money to get them home). The craft would weigh, by the way, about 8927 kg. These are most conservative estimates, and if someone can give me actual figures for my guesses I would be more than glad to do the math to figure them. Maybe later I will figure how long it would take to get to alpha centauri. The craft accelerates at about 3.36*10^-4 m/s^2 and would be going about 5.7*10^9 m/s, which leads to some interesting questions, since that is nearly twenty times the speed of light. When I sat down to do all this math, I thought I would debunk this technology, but really all I did was show that it unfurls even more questions, and that possibly all of you may be able to guess that I am doing poorly in my AP Physics B class.
someone needs to lay off the himalayan insane peppers...
/* oops I accidentally made a comment, sorry */
The trick, of course, would be to use less energy running the 'sphere than you would gain through mechanical energy.
Now I've got this mental image of a giant Sipping Bird on the Moon. Thanks a lot.
Transcript show: self sigs atRandom.
-obvious- the speed of light is 186,000 mph, making that the terminal velocity for any matter, although you would need an infinite amount of energy to achieve that speed -/obvious -
therortically though, you should be able to go as fast as you want, but at some point wouldn't you accelerate to the speed of the solar wind (assuming solar wind is a constant force, and does not cause constant acceleration), and once you go the speed of the solar wind, you'd have to use your own means to go faster than ths speed of the solar wind, and to top that, you have to push against the slower solar wind with your magnetic bubble, which would in turn act as a brake.
moox. for a new generation.
Every posting mentioned that in order to turn around or get back to Earth, all you have to do is turn off the magnetosphere to ride a gravity field to get back, but if you turn off the field, you are no longer protected from cosmic rays. Also, planets are not right beside each other at any one moment. And plus,isn't the solar wind emitting in all directions outwards from the sun? How would you be able to travel across the solar system then? For example, suppose you are traveling to a planet orbiting at the opposite side of the solar system, wouldn't an additional method of propulsion be needed? Further this article also does not address issues such as how a spacecraft is protected from space debris and how fuel can be replenished for long trips.
... or like running out of gas in the middle of the extra-solar space. yuck yuck!
Ok, Is it just me or does this look amazingly like the Star Trek "Warp fields"..... Use something along the lines of the ST nacells and you get more elongation to your field. (Ok I don't know how multiple fields might interact, but there's another way to gain a little control.) Also as long as your not talking about supra liminal velocities just stick a couple of "feild generators" out on some sort of boom arm and there you have some steering control with more or less pressure being applied to one side of the craft or the other. X wing them for more than one plane of control.
For additional thrust (at least at the onset, or possibly for breaking) vent the plasma gases, that you just used to expand your field, through a nozzel.
But you've forgotten that the accel is continuous, not a single burn. As soon as you're going farther than the moon, you're saving time.
.01 m/s/s acceleration (.001*g, or 10N acting on 1000kg), a 1 AU trip takes 1,521 hours, or half as long.
With a (helluva) rocket that gets you to 50,000kph in one extended burn, a 1 AU trip (150M km) takes 3,000 hours.
With a solar sail that gives continuous (and puny)
(Neither of these take into account the time to brake, or my poor arithmetic. But plug in t = d/v versus t = sqrt (2d/a) with your favorite numbers and you get the idea.)
"You can't get something for nothing." - my grandfather, on the stock market and Reaganomics.
Where is the Grammar Nazi?
You wouldn't say "regaling I," so why say "regaling my friend and I" ?
-Pete
Mmmm....Magnetic bubble things...good...*drool*
PRAY FOR MOJO
Is this much different from this?
Since I browse comments at +3 to sift things out (unless moderating of course), someone else may have posted this reposting of this story...or I may not be remembering the stories correctly but this really rang familiar.
Doesn't terminal velocity occour because of friction? In space, this would not be an issue.
Of course, this report is just a tad late. CNN had a story on this in January. I don't know if it made the web site, but I did see it early in the morning in one of their science/tech segments. I remember it because < name drop> I used to work for the guy. < /name drop>
Loads of possibilities, though:
PRO: Not only do you get continuous thrust, but you get uniform uniform. As the spacecraft moves away from the sun, the mini-magnetosphere will un-deform (if that's a word) so that it has a larger apparent area with regard to the sun, thus trapping more particles. Of course, the closer to the sun you are, the more the field deforms, and thus, less "sail"-area. There are limits to the amount of thrust you get depending on your field strength and distance from the star.
CON: You only get thrust according to the strength of the solar wind. Thus, you get no thrust on the dark side of planets, and no thrust while inside a planet's magnetosphere. Heck, you couldn't even have the thing on near a planet unless you have very accurate plots of its magnetic field, because the consequences would be indeterminant. You also can't be exactly sure how much thrust you're getting because the strength of the solar wind is in no way constant or uniform. You'd have to be continuously re-adjusting your flight plan and field strength to stay on any semblance of a course.
But, heck, you're getting a nearly free ride! Done properly, you don't even necessarily need coils... remember that you can generate a magnetic field from a rotating cylinder. Moving charged particles, yadda yadda, doncherknow. You'll just have to generate the power to spin the cylinder (and the nonconductive counter-cylinder so you don't torque your spacecraft into a tizzy), bolt the thing firmly to load-bearing members (the force comes through the magnet), and get ready for the slowest acceleration you could even hope to barely notice.
So, no, you can't use it for a launch system, and no, you can't use it for orbital corrections, and no, you can't direct the thrust, but at least you don't have to toss four fifths of your craft's mass out the back end to get anywhere.
Easy. Just reverse the polarity!
actually, since this method of 'propulsion' uses the solar wind, it would be a pretty-much one-way trip. solar wind radiates outward from a point source (the sun, in this case), so your craft would constantly be pushed away from the sun. there's not really any way you could 'steer' the thrust to give you a lateral push. this is the same kind of problem that a light-sail propulsion device has - you can't exactly 'tack' against the solor wind...
As you can see, being involved in the space program can be quite dangerous. Before you all ask "Does it run Linux?", you should think to yourself, "Should it be running at all". The USSR's space program, with actual successes like Mir, unlike NASA's empty promises, is the right space program to be involved with.
Shine on, you crazy diamond.
Hmm, if I traveled into the past and wanted to leave a message for future generations, I would use a giant laser to carve the message into the moon. It would be, CHA- but then get cut off as my laser was destroyed by a 400 pound blue idiot.
"Destroy science and religion. Science would re-emerge exactly the same; but not religion." - Penn Jillette, paraphrased
Hey maybe thats what they used in that movie i watched when i was little called Explorers ;)
Who wouldve thought?
http://www.livejournal.com/users/cixel
You shield and direct the magnetic field such that it is flat, then you turn is sideways to the magnetic wind. Just as in sailing, instead of going straight out in front of the wind, you will tend to drift sideways. You can use this effect to decrease your orbital velocity and then let gravity pull you home.
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
This sounds *bizarre*.
:)
However, the proof is in the pudding. Since I find it hard to believe everything in this article, I'll wait until 2001 and see if it happens.
If it does, then I'll say "Wow..." again.
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pb Reply or e-mail; don't vaguely moderate.
pb Reply or e-mail; don't vaguely moderate.
Yeah - thats the thing, these devices would send you on a one way trip. Thats not such a big deal for a probe, but I dunno how happy astronauts would be about that.
Although I guess that the Lorentz force (is that the one? charged particles in a magentic field) could provide some radial acceleration, but would the magnitude of this be sufficient to aid in a return trip? Interesting idea anyway, but I still reckon all we need is a couple of stargates 8)
Maybe we'll meet some big assed aliens, too.
Of course, we still don't have a cheap way to get to orbit. Thanks, NASA.
At any rate, to answer a few questions I've seen posted here:
1) Yes, the basic concept of a solar sail is sound. It has been tested, and it works.
2) Yes, the acceleration is low, but it is continuous. That fact, plus the fact that you don't have to carry (much) fuel, put's you WAY ahead of any chemical rocket solution.
3) The magnetosphere wouldn't hurt the crew or the onboard electronics: you just put the lifesystem inside a Faraday cage.
4)And YES, you could come back from a mission to, say, Mars, using this technology. Travel between planets is accomplished by establishing yourself in an eccentric orbit that passes through the orbital path of both your origin and your destination. So you can use the magneto-sail to push out away from the planet, establish your orbit, then turn it off when you reach the "top" of your curve, and fall back in. Then turn the sail on again when you need to brake.
Depending on the location of various planets, you could also use the sail to travel out, develop alot of speed, and then slingshot around another planet to turn yourself around and head back home.
"Research is what I am doing when I don't know what I am doing." -- Wernher von Braun
I have been reading alot about alternative propulsion as of late, and this seems by far the most realistic approach. While we are not going to see this in action for some time, it opens a ton of possibilities for countries like China that are just venturing into manned space flight.
With the amount of money the US Government has tied up in the Shuttle program, it is unlikely that they will even attempt implimenting this kind of technology on anything other than a "Test Platform" for at least 10 or so years. However, a country like China that is relatively new to the "Space Race" could easily use this kind of technology to attempt large scale interplanetary expiditions, with a far shorter time-line than competing countries.
Wouldn't it be something if the Chinese were the first to put a man on Mars? Don't laugh, it could happen.
I am become Troll, destroyer of threads
Being a sailor, I love the idea of sailing around the planets :-)
Thinking about it thou, downwind anything held out would probably work. Upwind is another matter, with no foils under water to provide lift I cannot see this being viable for coming back. Rather than thinking of it like sailing think more of kite flying, very,very big kite flying.
This just sounds like the NASA PR machine at work, must be time for budget submission.
Factoring in all the extra weight for return equipment (booster rocket, fuel, fuel, fuel) the solar engine takes longer to accelerate.
Of course it does. A one minute burn at one G (9.81 m/s^2) would produce a velocity of over 2100 km/hr. But try steering at that speed.
Also consider that returning to a stop would require as much fuel as accelerating. It's best to go slow in-system, so you can see what to avoid, and save the top speeds for outside the solar system where there is, theoretically, less junk to run into.
NecroPuppy
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Godot called. He said he'd be late.
I like you, Stuart. You're not like everyone else, here, at Slashdot.
You can tack in a sailboat because you have the water to push off of. Without anything to push off of, there's no way to work your way upstream using solar sails. -- Michael Chermside
Ya but who would volunteer to ride the thing? Sure there are bold test pilots that would ride it Venus with no way back just for the hell of it. But would they still be as eager after learning the level of magnetic force involved would likely cause sterility?
Hey, if M$-Word's grammar check says that it is okay, then it must okay.
Utopia is a direction not a destination.
It's called an elephant's trunk whereas it is in fact, an elephant's nose, a nose by any other name would smell as sweet
I suppose I'm going to have to give the proper response to this: You keep the bubble on full the whole way.
Assuming two stars of equal solar wind, half way there, you're not being accelerated by the wind of either star, but you're coasting along at your highly accelerated rate. As you approach the other star, its solar wind begins to dominate, slowing you down to a neat stop at your destination.
THEN you turn off the bubble!
In a real example, Just adjust your bubble up or down as you go, according to the difference in solar winds.
"You can't get something for nothing." - my grandfather, on the stock market and Reaganomics.
Leave the magnetic shield on, just cut the ionized gas to the shield shrinks
Time is an Illusion, Lunchtime doubly so -Douglas Adams
This could be interesting. It's quite easy to manipulate the shape of a magnetic field (cf the torus-shaped fields used in fusion experiments). Maybe it doesn't have to be a bubble. Maybe it could be disk-like, and thus present a wide area for less energy than they figure for a spherical bubble. Hmmmmm....
"You can't get something for nothing." - my grandfather, on the stock market and Reaganomics.
but even if you tilt a light sail 45 ', you're still going to be thrust out radially away from the sun. momentum transfer using solar wind is radial to the sun, and tacking isn't going to change that. all you would do is reduce the effective area of your sail.
Still, it ends up going REALLY fast :)
firstly, they'd be state of the art beowolf clustered embedded-rom linux boxes with quantum/holographic cube harddrives, immune to EM fields, all thermally powered by hot grits. oh, and they'd be used to view natalie portman pictures-interstellar travel is long and can get lonely :)
moox. for a new generation.
186,000 mps (second). 186,000 mph would equate to 51 miles per second. It would be cool if light travelled the same speed as sound. Think how weird that would be.
I believe the term is "Warp 0.000278"
Uhh, part of the reason tacking in water works is because of the force the water exerts on the boat. There is no such force in space.
:-)
So, want to try that idea again?
They said it would accelerate from a standstill to 80 km/s over a period of 3 months. A little math:
(80 km/s / 90 days) * (1 day / 24 hrs) * ( 1 hr / 3600 s) * (1000 m / km) = ~0.24691358 m/s^2.
For comparison, acceleration due to gravity on Earth is 9.8 m/s^2, about 40 times as great as the passengers on this craft would experience. They'd be fine.
Did anyone notice they said the speed would be about 180,000 miles per hour in 3 months? The speed of light is about 186,000 miles per second, so traveling to the sun would only take about 21 days from earth's orbit. Now where did I put my pf 3 million sunblock...
science is a religion
I've seen several questions about how to 'tack' back into the solar wind to get back to earth. With a conventional solar sail its pretty straight forward.
A conventional solar sail works by reflecting particles/light/etc and simple action/reaction. to go out to mars for example it is angled in a way to reflect particles away from itself to increase it's orbital speed; faster orbital speed puts the vessel in a higher orbit in the solar system. Coming back simply means angling the sail the other way so that the reflected particles slow the orbital speed untill the orbit lowers back to earth.
My understanding with a magnetosSPHERE sail is that it cannot by it's nature 'tack' back into a lower orbit as it is sphere shaped; It acts much like a parachute rather than a flat sail.
To tack such a vessel back you either have to figure out a way to 'flatten' the magnetic sphere into more of a disk shape that can act as a conventional flat sail. The other alternative is to use a planet's gravity to 'slingshot' you back the way you came.
You could probably 'flatten' a magnetic sail by using a large torsional (donut-shaped) ring to create the magnetic field. Older magnetic sail designs I have seen used a superconducting cable in a loop which naturally repelled itself and created such a shape but these early designs did not incorporate the 'plasma boosting' the new design displays.
-- Greg
Slashdot, would a spell-checker for posting be too much to ask? It's not rocket science!
Can someone who understands the actual physics of this propulsion explain it in terms that someone with some physics knowledge could understand? I'd like to know how they really get magnetic field amplification from plasma.
The same approach would let you fly from Earth to, say, Mercury.
"Research is what I am doing when I don't know what I am doing." -- Wernher von Braun
Tacking works on a sailboat because the keel has the water to push against, so the vector of the force exerted by the wind that would push the boat in the wrong direction has a contervailing force. A spacecraft wouldn't have the equivalent. To return, I presume that you'd do it the same way as you got to whereever you are (assuming that it's near a star): unfurl the sail and let the star accelerate you, then drop the sail when the solar wind from the destination exceeds that of the star you're using. Of course, IANASS (I am not a solar sailor)
Since the moon doesn't have a magnetosphere couldn't you put types of these machines on the moon as power plants.
:-)
You have one of these machines on an extremely long slanted pole. Slanted meaning slighty up from the moons surface. When you turn it on the solar wind pushes on it. You have a tether to a generator. The tether pulls on it creating power. Once at the end of the pole the machine turns off. The small amount of gravity on the moon pulls it back. Once it is back in its starting position it turns back on and the process starts over.
Sort of like a windmill, moon style
I had remembered that a black sail would work as well, but after a few minutes of drawing vector diagrams, I can't see how.
Replying to someone else's point about using several bubbles tethered together: I can get some tangential thrust if one is 'shaded' by the other, so the rear one receives solar wind only on one side. There is also a torque that will tend to spin the tethered bubbles, but this can probably be counteracted by clever uses of magnetic fields reacting against the solar magnetic field. This isn't very efficient in terms of sail area to useful thrust ratio, however.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
I would assume that you can tack against the wind...seafaring bipeds did this often only a few short hundred years ago...
I'm not awake enough to figure out the geometry involved, though.
What's this Submit thingy do?
But then you'd end up stuck to the refrigerator.
Science fiction has indeed tended to preceed then-current technologies...and science fiction also tends to get people interested in one specific field or another.
:)
One very easy(but not often noticed) case of science-fiction -> science fact:
Waterbeds.
In Heinlein's Stranger In A Strange Land, Michael was placed on a bed for his safety on the return trip to Earth. Heinlein did a good enough job describing how the bed worked that somebody went out and started making/selling the things.
I know I like mine.
What's this Submit thingy do?
tacking uses two forces (the wind and the resitance of the water). In space, you have solar wind and you have grvity. *should* work... Oh, and this is not well thought through at all, so you may have to > /dev/null
--The knowledge that you are an idiot, is what distinguishes you from one.
Be ot or bot ne ot, taht is the nestquoi.
Actually, I suspect that it went the other way. Trek fx creators probably based the looks of the warp bubble on the shapes magnetic fields take. And the looks are sorta similar, but I can't see why you think the concepts are ...
TO be honest, this was the _first_ thing I thought of.
:)
:)
Magneto's force-bubbles.
Nice to know Real Life imitates art. Although, somehow, I don't think he's filling them with plasma, as even Magnus needs to _breathe_.
Damn, I am a Marvel Comics Geek.
Redhawk
Piers Anthony had a series called
"Bio Of A Space Tyrant" 4 or 5 Books. In this series Giant magnetic balls were used as spaceships. By sheilding the magnetic field on one side or the other the bubble was drawn towards the planet or away from it. Any one else remember this ?
In the previous article, it was mentioned that this idea was in the "dream stage" of development.
The above article indicates that the first round of testing the devices has met with remarkable success. This is news for us nerds that the concept will be far more than just a dream! I'm quite happy this was posted.
This is definately stuff that matters, and news for nerds.
Bork! Bork! Bork!
Even if there's no way to take a trip home with it, would it be a cheaper way to build the ISS and shoot up satellites?
I don't know if this technology would be a candidate for interstellar spacecraft, but if it is, you could always just push off from the destination star to start the trip back.
I wonder what the "terminal velocity" of this system would be? If you start off close to a star and just sail away, how fast would you be going when the acceleration finally peters out?
MSK
So, if this is small enough, and made with off the shelf parts, can I get one of these on a belt perhaps?
Aaah, not you! Quick, shields up!
Hmm....
It doesn't use radio for communications. It uses IR.
-- Anne Marie
Basically, accretion disk around the object pulls the field lines inward. This only affects the region of the lines close to the disk. So, basically the field gets squished in at the equator. However, the lines are also constrained to remain perpendicular to the disk, so when they relax they also tend to inflate.
This effect depends on having a "halo" of plasma around the object (ideally it would be infinitely conducting), combined with the resistive accretion disk.
It sounds like you could just bolt this new device to the floor of a shuttle's cargo bay and have yourself an interplanetary cruiser. That would make shuttle trips to places like L1 or a lunar base not only viable, but downright dirt cheap, and missions to Venus, mars and the asteroids well within reach. I am not too sure on how it works, but there is a technique that sailing ships used to travel into the wind (tacking?) for the return journeys. The biggest concern would become cargo space for life support: air, food and water, rather than fuel. The future is finally with us!
One really exciting use for this would be to attach drives like this to asteroids. This would first and foremost serve to save the Earth from any imminent collisions but would also allow you to re-position juicy asteroids closer to home, etc. All you need to do is bolt the coil and a power generator to the surface, and voila'! the rock will be moving 180,000 km/sec within umpteen units of time.
Let's just assume the m2p2 drive will make it. The next holdup will be attaining orbit. I predict that either one- something similar to m2p2 is developed to launch cheaply using the Earth's own magnetic currents. Launches would take place at one of the magnetic poles (finally, a use for Antarctica!) and will be simple and sturdy like the m2p2. OR two- the application of the cavitation bubble can be used for building up hypersonic speeds (escape velocity) without much friction and without fighting gravity. A damned Mack truck could attain orbit with a system like that.
One further thing strikes me as curious about this. I know it's pretty far-fetched, but the [douglas adams/joseph campbell/tim powers] tainted conspiracy theorist within urges me to mention it; The name m2p2 bears a close resemblance to the city 'machu pichu' one of the absolute most vexing mysteries in human history. The architects of that ancient city were able to bring large rocks (massing dozens of tons each) to a remote South American mountain peak many miles from the quarry of origin. When you ask yourself "did they use m2p2 to build machu pichu?" and take into account the permutations and perversions of language drift, a suspicious coincidence in phonemes comes to light... I wonder if a band of space adventurers stumbled back in time and tried to leave us a message or hint?
:)Fudboy
:)Fudboy
I guess I'm only a Fudboy, looking for that real Transmeta
That's not entirely why tacking works for a sailboat. When you set a course diagonally into the wind, you get force applied in two directions.
One, is the wind pushing into the sail. This is somewhat countered by the water, as you mentioned. The boat generally doesn't want to move sideways.
But the airflow over the sail creates lift, much like an airplane wing. That's where you get the majority of your momentum. This force works along the length of the boat, where there is little resistance from the water.
If you could create a difference in the speed of magnetic currents, then you could create lift. Which would allow you to tack. Ask the guys at NASA though - I have no idea how this would work.
That guy's not kidding about becoming the furthest man-made object from the sun. 80km/s may not sound like much after three months, but note that, amazingly, acceleration will remain constant because the size of the bubble will increase as the pressure of the solar wind decreases.
I did a little bit of math, and came up with 392 days to pass Pluto's orbit, at which time the probe would be travelling at a speed of almost 350 km/s. That's more than 0.01c, so we'd have to start figuring in relativistic effects, but damn that's fast.
Note: I'm on my co-op term now, so please excuse any mathematical mistakes as my brain has been turned off.
It may look like I'm doing nothing, but I'm actively waiting for my problems to go away.
--Scott Adams
That was the ultimate Bad Idea. The telephone sanitizers, middlemen, etc. do not die in the vacuum of space. By some extraordinary chance, they crash into Earth and become the basis of it's [un]intelligent life.
-Splat
This comment reminds me of a not-very-well-known H. G. Wells story called "The First Men on the Moon." Some crackpot inventor came up with a material that sheilded gravity. By covering a spherical spaceship with this, and then opening a "shutter" in the direction you would want to go, any mass in that direction would pull you towards it, whereas the sheilding layer would prevent all other mass from acting on you. All of a sudden, you were accelerating in the direction of the open "shutter."
Isn't science fiction great?
It may look like I'm doing nothing, but I'm actively waiting for my problems to go away.
--Scott Adams
the article says their magnetic source is about three times stronger than a refrigerator magnet. somehow I don't think that will cause much trouble for any electronic or biological systems present in this type of spacecraft.
Oh wait, you are going to the Sun, and not returning back to Earth....
Oh shit....
Comment removed based on user account deletion
I saw a mention of this several months ago and imediately thought of the perfect application of this tech.
Take two long (and strong) cables about 30 km long. Strap two magnetosphere generators to the ends of each cable so you have two floppy dumbbells. Attach the centers of these two cables together with a generator along the axis. Face the construct so that the axis is perpendicular to the suns rays. Turn the opposite ends of the two cables on until they spin around the common axis and are heading towards the sun. Then you turn on the other generators until they spin around. You can pull all that energy out with the generator. If you run simple numbers the energy gets huge very fast.
Later
Mick D.
Is this the end yet?...How 'bout now...how 'bout now...how 'bout now?
From the description I got in the article, I think sailing is the wrong metaphor for this concept. Kite-flying is closer, but I think the best current-tech analog is that of a submarine ballast tank. After all, doesn't the system basically change the vehicle's magnetic "ballast" causing the vehicle to "rise" or "sink" in and out of the Solar System?
Am I on to something here, or just blowing my ballast tanks?
I just watched Crimson Tide last night so maybe that's influencing my viewpoint.
Averye0
--o You're just jealous cause the voices talk to me and not to you! o--
Can some one with a better grasp of inter-planetary physics comment on whether you could use the space shuttle to launch small vehicles using this technology?
I know the space shuttle doesn't _really_ travel in space by some people's definition but how much force does it take for a comsat or something of that mass to get away from Earth if launched from the shuttle bay? If nothing else a test vehicle to demo the theory could be hoisted up and turned on to see if the idea works in practice.
What about the same idea from the space station? And/or use it to help sheild parts of the space station and help it mantain orbit using less power?
=tkk
Bill Gates - Creationist?!?
.. is that it only goes one way... and once you get a certain distance from the sun, you start going really slow. The 1:600 energy ratio would be quite helpful in using less fuel, and these types of things would be great for one way trips, and as plasma shields for deep space probes and satellites. Satellites that used a smaller bubble(small enough not to catch enough wind to be knocked out of orbit) would be safe from the solor radiation that occasionally knocks out satellite communications.
Shit adds up at the bottom...
And one way they could do it with out planets to slingshot around would be to use some type of railgun, which the technology isnt quite ready yet, but it could be soon... I also think railguns would be a much more cost effective to actually get the spacecraft into space. No huge rockets needed, just some bigass magnets, and a ship capable of handling the acceleration...
Shit adds up at the bottom...
if you just turned it on and let yourself drift, youd go out of the solar system and run up against the next star which would push you back the other direction so youd go in a third direction and eventually wind up in a static void from the magnetic fields between stars. Sounds like a great place to put equipment for either monitering any objects entering the solar system or interstellar communications. a sort of heliosynchronous orbit in our local group.
http://www.livejournal.com/users/cixel
That reminds me of a guy I met at the Psychic Fair (don't ask) back in High School. This fellow began regaling my friend and I with stories of how everybody's soul fractures upon death and enters other people's bodies. He proved this with Kirlian photographs showing Marilyn Monroe's and Plato's faces. Apparently he developed a way to communicate with these folks, and they told him that he needed to colonize other planets because the Earth was dying.
The technology they told him to use for space flight was demonstrated to my friend and I with a small apparatus. It looked like a simple toy you'd find at the Science Center. A wooden stick, about the size of a pencil, had a disc-shaped magnet stuck at each end. The tip of the pencil was placed on a slanted surface perpendicular to another set of curved magnets. This caused the pencil to float.
Our new friend showed us that we could build a magnetic space fleet similar to these devices, and told us how they'd escape orbit. He spun the pencil around, and he pointed out how it begin to wobble. Then he spun it harder, and it jumped out of its magnetic cradle! Amazing! (We were having a really hard time not busting up at this point).
He finished with his plan to pull giant icebergs from the asteroid belt to Mars, and we quickly made our escape.
I'm not sure what happened to him. Maybe he got a job at NASA.
angle the plasma generator. this would cause a bulge in one side of the field & create an angled surface facing the sun. as the solar with hits the angled surface, you're propelled in a different direction. (not that i've studied any of this...)
Haven't you heard of inertia? the ship wouldnt stop, until it hit something, or got to another star, and turned on the magbubble brakes... Once something is moving in space, it doesn't stop. Such is the benefit of a air frictionless environment.. So you would have to get to a planet, or a star to stop.
Shit adds up at the bottom...
I would imagine that once the bubble is inflated with plasma, that you would not need anymore fuel, unless you deflated it, but you could catch the gases when you deflate, so that wouldnt be an issue...
Shit adds up at the bottom...
(1) Force = Mass rate * Exit Velocity
(2) Power = 1/2 Mass rate * square of Velocity
Rearange 2 to solve for exit velocity from the given mass rate 1kg/day /24 (hours/day) /3600 (seconds/hour), and power 1000 Joules/second, then plug it back into the first equation to get force in a perfect world with no losses of power.
Now this is a fine multiplication, but it's still a low absolute force that needs help and mission times will be long. While it is least expensive to change your orbits at infinity, you will still need some other propulsion system to do it. Then, of course, you might want to make some course adjustments when you get closer to the target. Consider the period of other bodies that orbit the sun, like Hales commet to get an idea of how long it might take you to get places this way. Then remember that you will have to turn your shield off while you fall back, Ouch! I need another shield! Ohhhh! the solar winds are not my friends! Better to use this to move supplies.
Slingshots are cool, but if your only travel direction is a radial arc, you might have to wait a while for a planet to be in the right place.
How about using a minimal solar sail that acts like fins to guide the spacecraft in a general direction? Also I wonder if they can concentrate the plasma they inject into the magnetic field to be more concentrate on one side or the other of the magnetic field to aid in navigation or perhaps have it so concentrate on the side facing away from the sun along with a solar sail arm on the spacecraft reflecting the solar wind to propel it forward TOWARDS the sun.
http://www.livejournal.com/users/cixel
well, you couldnt go faster than light speed, thats for sure.. depending the the sail size to ieght ratios it could be anywhere from much slower, to very close to light speed.
Shit adds up at the bottom...
I wonder if you could slingshot around the earth towards the sun, and fire up this sucker near a solar flare to see how far it would shoot you out of the solar system. The force on your magnetic field would be insane which would either kill you or propel you like mad out of the solar system. Suddently this makes lots of things in the solar system managable. Think robots dispatched into space to latch onto asteroids and propel them to near earth orbit (dangerous terrorist weapon OR raw material mining?), because most asteroids are further off you could slingshot an asteroid around a planet with one of these and send it back towards earth or keep it in orbit around the moon. The scifi implications of this stuff will keep people thinking for years to come.
http://www.livejournal.com/users/cixel
Jeeze! You people amaze me! "How are they going to get back?" "How do you slow down?" "How will any electronic device work inside the bubble?" Lets face facts. 1. Congress will never approve the budget. 2. NASA doesn't have the best track record of late with either its systems or it's math skills. For the most part the whole idea is a moot issue. But even if they did build it, until they can remember that there is a difference between kilometers and miles they'll never find anybody crazy enough to ride in the damn thing! :)
Carpe Scrotum - The only way to deal with your competition.
Who wants to come back? I'm outta here. Alpha C, here I come!!!
I am quite civilized, and I should be brought a beer immediately. -- Bruce Sterling
If this were sent to another solar system, it would use the Earth's sun to get it half way or so then it would use the solar wind from the destination star to slow it down. It would be like running _into_ the wind. This would slow it down, and bring it to a stop.
Also, there are other ways of slowing down. Using gravity would be one example. They use it now for boosting the speed of satellites and other space equipment. But remember that this can be used to slow something down. Much like the way things are drawn into the sun, or a black hole, or a planet. Remember the comets that struck Jupiter not too long ago? Obviously they slowed down enought to fall into Jupiter's gravity well.
Getting back from trip out to the planets could use the same principles. Get a boost from a planet and redirect back to Earth, turn off the sail. Get closer to Earth then hit the brakes by turn the sail back on.
Without gravity to assist on the accelerations (whether positive or negative) many other alternative ways could be devised to slow down and stop. I'm sure you don't lack the creativity to come up with other means. (maybe a magnetic cannon or something)
That movie was great . . . the small sphere thing shootin' around the basement . . . teenaged peeping toms . . . feeding the junkyard dog gum . . . sound bite spouting aliens . . .
Wait a minute!
I friggin hate those aliens!
They F-ed up another perfectly good movie with a lame-ass, hail-mary attempt to end the movie.
I guess they didn't realise that moldy bread is the only TRUE interstellar lifeform.
I've stopped washing (everything) in fear of the damnation I'll recieve for throwing all that "rotten" food away.
And now we know what "shrooming" is really about.
Dirt doesn't need luck.
A force radially away from the sun does very little for you. The solar wind force cancels a tiny portion of the solar gravity, with the result you end up in an orbit just slightly larger than before you turned on the sail.
To get anywhere, you need a component of force along your direction of motion. In 'traditional' solar sailing, this is achieved by putting the sail at 45 degrees to the solar radiation. If the tangential force acts in the direction of your motion, your orbit steadily grows. If it acts against your motion, your orbit shrinks.
So far as I can see, this proposal produces an approximately spherical 'sail'. This would not allow tilting the sail to produce a force component along the orbit. However, they don't discuss the shape of the bubble, so I may be going astray here.
As an aside - from memory, there is about 10 times as much pressure available from the sun's light as from the solar wind. This method doesn't use the light, whereas 'traditional' solar sailing does. This advantage is likely overwelmed by the ability to make a large 'sail' cheaply and lightly with the bubble method.
(My solar sailing experience is limited to setting an undergraduate assignment on the topic some years ago.)
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
and even worse...if you notice you're on a collision course with some asteroid, comet, or other space thing how do you change course to avoid while traveling at that kind of velocity?
But then they would lose the magnetic shield that the propulsion system gives them. Worse, coming back they would have to counteract the force exerted by the solar wind.
--locust
Slow relative to what? Gallagher said "That's enough to accelerate a 200 kg spacecraft from a dead stop to 80 km/s (180,000 mph) in only 3 months. The mean distance to the sun of Pluto is 5,913,520,000 km, so by the time this buggy hit the edge of the solar system, it would be going hella fast, relative to what I think is slow.
OK, so your riding the solar wind along at 80KM/sec....all the sudden you see a star you are running straight into...Hmmm how would you stop or turn?
Call me when they find something that makes getting out of the gravity well as easy as this thing sounds like it is.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
uhh, no, ever heard of friction? dont waste your time with perpetual motion, its impossible... however, you could get very close...
Shit adds up at the bottom...
Isn't this how the characters of the movie "Explorers" achieved space travel?
[its been a long time]
uhhh, we are in such a field right now... ohh no.... but, really the field protects much more than it could possibly harm. No radiation.. I agree with space habitat stuff... when are we going to have those orbiting space platforms a la the skyhook from SotE? we could even mine on mars, so we dont waste any more of our precious resources... this is nothing but good news...
Shit adds up at the bottom...
Hasn't anyone ever seen The Explorers?
The article didn't go into this, but how would a vessel equiped with such a propulsion system return to Earth?
Could it tack back into the solar wind for the return trip?
NecroPuppy
---
Godot called. He said he'd be late.
I like you, Stuart. You're not like everyone else, here, at Slashdot.
Wouldn't it be something if the Chinese were the first to put a man on Mars? Don't laugh, it could happen.
would that make Mars the Red Planet?
---
I post links to stuff here
The one immediately obvious drawback is that it is relatively slow. Another question that comes to mind is the effects of such a strong magnetic field on electronic devices within the field. Or for that matter, the effect on biological systems within such a field, especially over long periods of time.
But if nothing else, the team at NASA has apparentely developed an inexpensive solar radiation shield, especially useful for deep space exploration or space habitat use during solar storms. . . .
If 1kW only gets you 3N, you had better get one hell of a long arm.
I never really understood the concept of solar sails. Someone out there clear something up for me... if you have a huge sail propelling you through space, what's to happen when a piece of space debris flying thousands of miles an hour tears a hole through it?
Actually, this won't work in atmosphere, so it's not a way into space, as it's just a special case of a solar sail. However, it looks like a pretty nifty way to go to the outer planets once you are in space. Maybe this could be used for a new Pluto Express mission. Coming back could be a problem... I wonder if you can tack against the solar wind?
jim
I've wrestled with reality for 35 years and I'm happy to say, I finally won out - Elwood P. Dowd
This sounds cool, but from the sound of it, it only works one-way!
The article talks about family flying saucers, but it doesn't mention how you get back after you zip off to Jupiter. Of course, considering some of the loony stuff happening on Earth lately, maybe you can't blame them for conveniently forgetting a return path.
We want endless gardens of data, where the bits can flower, flourish and reproduce. -- Andy Mueller-Maguhn
This is old hat. Smart money these days is on quantum teleportation an neutrino masers. NASA is about fifteen years behind the times.
How do they plan on getting back? This works fine for probes and all, but I want to send -people- to other planets. Factoring in all the extra weight for return equipment (booster rocket, fuel, fuel, fuel) the solar engine takes longer to accelerate. I think the best part about this is DEFINATELY the shielding against solar radiation. I'd like to see one of these which shields the radiation while not being pushed by solar winds. Think about a return trip from Mars. Do you want shielded, or do you want less drag?
The REAL sam_at_caveman_dot_org is user ID 13833.
If you need 1kW just for a 200kg craft it means that the power requirements for a manned 30 tonne mission will be pretty high. Where do you get all that power? Solar panels are heavy and not very efficient.
I guess this calls for unpopular power sources such as radioisotope thermoelectric generators.
----
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
There is no such force in space
In a word, gravity.
Yes, it's the force the water applies to the keel, counteracting the sideways force of the wind which allows a sailboat to sail upwind. FYI sailing on water the vessel moves forward by using the wind to generate lift (like an airplane's wings) to pull it forward, whereas space sailing movement is generated by action/reaction (like a rocket motor) so they are two completely different methods.
The 'keel' a solar sail uses to get closer to the sun is the sun's gravity itself. As the solar sail changes it's speed by reflecting particles in the direction it's traveling and causing an opposite reaction away from that direction (i.e. slowing itself) the lower orbital speed makes it fall towards the sun.
The best way to explain it may not be by words; so try the solar sail simulator java applet and see for yourself.
A conventional solar sail will sail 'to windward' like a Farr 40, whereas a magnetospheric sail sails to windward like a Morgan OutIsland.
-- Greg (S/V Scirocco)
PS: In the future please double-check that you are 'right' before calling someone else 'wrong'.
Slashdot, would a spell-checker for posting be too much to ask? It's not rocket science!
Easy:
</EVIL>
DNA just wants to be free...
Eatrh's a dump.
Heck, even the whales are leaving -didn't you ever see Star Trek IV: The Voyage home or read The Hitchhikers books.
The evidence is clear -the fungi have reached us and now it's time to go.
Dirt doesn't need luck.
i know this is offtopic but perhaps one of the reasons we dont get any radio communication drifting in from alien telivision is because our stupid sun's magnetosphere blocks it all out. I know we scan the microwave channels too because theres little noise but think about it, we use microwaves for point to point communications because its more accurate, why dont we assume the same of them? As a civilization gets more into technology they begin pressing up against fundamental laws of physics which mold their technology. So eventually all of our technology should be the very close to the same.
http://www.livejournal.com/users/cixel
I found a really interesting article on this topic over here
.
.
Anonymous Dumbass - And you thought Anonymous Cowards were dumb!
the thoery for this was printed in a analog sci-fi magazine back in 93 or 94... i'll dig it up and publish the issue date...
ok, from this old message post comes the info on the publish date, it was actually in 92!!
Heres a quote:
"There's a cover-story article I've just read that I think a lot of you
will be interested in: ``The Magnetic Sail,'' by Robert M. Zubrin
(based on work by Dana G. Andrews (Boeing) and himself (Martin-Marietta).
I regret it appeared in an only *quasi*-reliable source: the "science fact"
section of this month's (May 1992) _Analog_.
"
man is machine
sounds like nasa has been watching too many movies.
You see a problem, I see potential. - Vincent 'Vinnie' Antonelli
Ita erat quando hic adveni.
I'm surprised NASA was inventive enough to think like this... they seem to me to always go for the "more bucks, bigger faster rockets" approach.... they tend to try to overengineer old technology...
This is a step in the science instead of engineering direction... a whole new way of doing things. Score one for NASA.
11*43+456^2
Does anyone else remember the movie that had magnetic bubbles, it think it was called 'The Explorers' and was about a bunch of kids that dream of how to do it and it turns out that it was some alien kids sending them messages while they slept.
;)
Maybe the movie industry will sue the guys that thought of this for infirngment of intellectual property
Why not strap one of these suckers to Venus, and boost it into a higher (earth-like) orbit? Power considerations would be incredible, but it would be so *cool*. I want my own planet mover.
I saw this in a movie called "explorers" once.
"I am a warrior, and information is my weapon..."
okay, who else has visions of comic book supervillain magneto and his magnetic bubbles?
:)
magneto put all kinds of fun things into space with his bubbles - space ships, people, asteroids, the Avengers: West Coast mansion...
maybe the guys at nasa aren't just watching Star Wars movies, but reading comics, too
- Entertaining Bits from the Ancient Kernel Tree
Wasn't there a movie that had three kids that made a spaceship out of a old tilt-a-whirl car and a bubble. They flew into space, met some aliens, and came back to Earth with a "DreamStone" of some sort...
Does NASA watch old 80s movies to try to get the next gereration techonology? Or do the NASA techies want there own DreamStone?
Wish I could remember the name of the movie...
Has NASA been watching too many kid sci-fi movies from the 80's?
They must be set back in their efforts without River Phoenix's computer program!
Great for travel out... exploration and all that
stuff but uh.... one small question...
If this were a space ship, how do you come back?
Old truckers never die, they just get a new peterbilt
If someone could come up with a way of change the relative size of the field from left to right then the difference in field size would help steer the vehicle.
TO get the vehicle out of Earths orbit would simply take some field maninpulation so that the pole are orientated in such a way that it is slung out of Earth's atmosphere. One way would be to place the vehicle at one of the poles and the matching poles would create a natural push.
On the subject of travelling outside of the solar system, there are some scientists that believe that space is actually very full of magnetic fields and that field voids are very rare.
Jumpstart the tartan drive.
Coooool.. Sounds like a freaky acid trip.
Ok, the working concept for a craft powered by solar wind involved a 300m wide sheet of 0.1mm thick carbon fiber fabric, or something like that. From an engineering standpoint, that is hellishly complex. The torque forces on something that would have to be small enough to launch complete by rocket, with a fold-out sail that enormous, are phenomenal. In addition, the solar sail's thrust is inversely proportional to the square of the distance from the sun, while the magnetic bubble expands as the wind gets more rarified, so the net thrust is the same at any distance.
The fuel efficiency of this thing is pretty respectable, too. 1 kg per day is a little expensive over the course of a long mission, but they expect their efficiency to improve, and they would also probably also not need the full power field during cruising legs of the trip.
The safety issue is the icing on the cake. This kind of thing would also make explorations of Jupiter easier, since Jupiter's equivalent of the Van Allen radiation belts give an exposure on the order of 5x a lethal human dose just to pass through at a speed reasonable for assuming a low orbit. Granted, there's not much on Jupiter for a human to walk around on, but if the radiation is 5x the lethal human dosage, your flight hardware needs to be very heavily shielded. This magnetic field frees up a lot of weight, which in turn increases the fuel efficiency.
Now if only they could find a way of sailing upwind in the solar wind stream. You can do it with a properly configured sailboat, usually within about 45 degrees from the wind direction, give or take a few degrees depending on various specifics. If they could do it with solar sails, you'd have a viable human-transport system. Otherwise, the best return mechanism you could use would be to go out on full power, swing around a planet (without stopping) and power down to just enough to protect the crew, and drift back on momentum.
WARNING: there is a trojan on your
Do the math. If I have a 200kg probe, and I expend 1 kg of its' mass a day for the sail/shield, then we're talking about a **100** kg probe which can accellerate for 100 days. . .
Bah, who was calling you wrong . . . you finished the definition for the uneducated (me). ;-)
I think the full paper is here:l _report/html/3Winglee/3Winglee.html
http://peaches.niac.usra.edu/files/studies/fina
"I object to doing things that computers can do." -- Olin Shivers, lispers.org
There is a website at http://www.geophys.washington.edu/Space/SpaceModel /M2P2/
that holds much more technical information. The
"Technical Report Phase I" appears to be broken,
but there is a white paper
here.
The amount of beauty required to launch 1 ship: 1 Millihelen
Why is so much effort put into getting off this rock rather than making it a better place... Utopia is not in the stars, it is where we make it.
flinging poop since 1969
It always amazes me how often science fiction predicts the future. This concept is similar to (and even looks like) the warp bubble idea in Star Trek.
One other approach would be to use such a field for habitat shielding. If you created a field around the habitat you would almost elminate the radiation in the living areas.
Jumpstart the tartan drive.
So you end up wth a hole a few inches, or feet
at worst, in sail square kilometers large.
No one would notice it.
No significant ind force to enlarge the hole.
You guys reported on this back in April: Magnetic Bubble Space Drive
include $sig;
1;
would it be possible to use the magnetic field(s) to divert the course of an asteriod that would otherwise cause impending doom to earth? perhaps by creating the field around the asteriod itself to help accelerate it either around earth or halt it completely if caught early enough?
>you can't exactly 'tack' against the solor wind...
Are you sure? Extend the lines on one size of the sail. The craft will be
off-center, and you should get outward and lateral thrust
as dictated by the cosine and sine of the angle at which the
craft protrudes.
I expect you could similarly steer with the magnetic sail by shifting the
generation unit relative to the main craft, creating such
an angle.
These won't give you outright directional control, but they could affect
the direction of your outward motion from the wind, or your
inward fall from gravity . . .
And the return trip could come by decelleration in orbit, and then
steering along the trajectory . . .
hawk