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Ion Engine Propels Probe to Moon
lenin writes "The BBC is reporting that Europe's first moon mission, SMART-1, appears to be a success thus far. It also talks about the low-cost technology being used and the charged xenon (ion) propulsion system. Can TIE-fighters be far off?"
Yes, I do know why ion engines are a good idea. Just leave Star Wars out of this.
Panurge has posted for the last time. Thanks for the positive moderations.
It also talks about the low-cost technology being used and the charged xenon (ion) propulsion system. Can TIE-fighters be far off?
Yup, that's how technology goes, straight from moon probe to TIE fighters. No intermediate steps necessary. No life support, no radiation shielding, necessary. I can't wait to buy my A-Wing.
For ever action their is an equal and opposite reaction.
Rockets move exactly in the same way an Ion propulsion engine would move. By forcing mass out the rear. Unlike jet or propeller, a rocket ejects its fuel as a means to propel itself.
(sigh) Then the Emperor has already won.
You are not the customer.
Sure the Ion drive is a really neat addition, but it's soooo slooooow. It's going to take them 15 MONTHS to get there! And the payload isn't really greater at all. It takes longer to get any large loads going. The US space program got people to the moon and back in what...2 weeks? It may be slightly more economical, but it just doesn't seem practical.
Hopefully they can perfect the ion drive, however through this to increase the speed and payload capacity. Then we might have something really cool... (until the anti-matter reactor comes online...)
If we combine this with the space elevator, we can send shit to the moon on 6 AA batteries!!!
10 ?"Hello World" life was simple then
Russia does far more launches than the US.
Russia does them much more safely. In manned launches, they have something like a 99.9% success rate (one launch mishap in over 1000 launches). The US has had two mishaps in about 115 launches.
Of course you don't understand - after all, this time it really IS rocket science.
Rockets use the same priciple that ion propulsion uses, the law of action and reaction (one of Newton's Laws, can't remember which one off the top of my head). Basically matter is accellerated out the back of the engine (by chemical means in the chemical rocket engine, and by using electro-magnetic forces in the ion propulsion engine). This accelleration causes causes a force to be placed on the engine that is equal to, but oppisite in direction, to the force accellerating the matter.
To answer your first question, Deep Space 1 used ion propulsion.
...interesting if true.
It's pretty simple, really. In the atmosphere, rockets work by pushing against the air, as you might expect. However, when the rocket leaves the atmosphere and enters a vacuum, or what we physicists call an "inertial frame," then your thrust is pushing against this inertial frame, which is kind of like what physicists used to call the "Aether." Aether has gotten a bad name, since Einstein proved that electromagnetic waves don't need to travel in the aether, but this has led to the misconception that aether doesn't even exist. Mach's principle shows that Aether is real, since it is what we need to push against to rotate and accelerate in space.
Banach-Tarski Overdrive
TO THE MOON!!!
Can TIE-fighters be far off?
There will be no TIE fighters until we have friction in space. To be able to turn like an airplane in an atmosphere you need something to react against.
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I am a programmer. I am paid to produce syntax not grammar. Deal with it.
If you are wondering how rocket propulsion can work if Newton's laws dictate that every force generates an equal and opposite force, you're not distinguishing between force and acceleration. If you mass roughly 50 kg, and I hit you with a 500 kg Acme weight with a force of 1 000 N, you'll accelerate at 20 m/s^2, but the Acme weight will only accelerate at 2 m/s^2. Equal force != equal acceleration.
Actually, no big mystery, it has enormous solar panels 10s of meters long.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"I think what confuses some people is that we're used to pushing against something to go somewhere. People have a misguided idea that it's the exhaust pushing against the ground that makes a rocket go, but it's actually the rocket pushing against its exhaust that makes it go. Basically, you mix two things together in a chamber, and under high pessure you shoot ("throw" in the parent's words) the resulting gases out the back end, and away you go. There's no need to interact with the atmosphere which is why rockets work in space and propellers don't.
While the Ion engine is very slow, it actually turns out to be faster then most engines in the long run. For a normal engine they generally burn real quickly then the object just coasts to wherever it is going. With an ion engine they can burn for very long periods of time. Over long distances it is better to burn for a long time with a slow acceleration then it is to burn quickly.
Even better, if you are doing something like flying to Mars, an ion engine combined with a normal engine has a lot of potential. Just strap a big old disposable solid fuel engine onto your spacecraft and let it burn dry. This will get you well on your way to your destination. Dump the solid fuel engine and continue to burn with the ion engine. You will get to where you are going fairly quickly.
We like the moon
Coz it is close to us
We like the moon
But not as much as a spoon
Cos that's more use for eating soup
And a fork isn't very useful for that
Unless it has got many vegetables
And then you might be better off with a chopstick
Unlike the moon
It is up in the sky
It's up there very high
But not as high as maybe
Dirigibles or zeppelins or light bulbs
And maybe clouds
And puffins also I think maybe they go quite high too
Maybe not as high as the moon
Coz the moon is very high
We like the moon
The moon is very useful everyone
Everybody like the moon
Because it light up the sky at night
And it lovely
And it makes the tide go
And we like it
But not as much as cheese
We really like cheese we like zeppelins
We really like them and we like kelp and we like moose
and we like deer and we like marmots
and we like all the fluffy animals
We really like the moon
The concept relies on using power from the solar cells to make the force. This is opposed to carrying fuel.
Using this system only a very small amount of mass is needed to accelerate the craft to quite high velocities, because the energy isn't lifted from the gound but produced in orbit.
On a normal probe the energy for popultion would reside in the fuel carried in tanks, here it resides in the rather large fusion reactor at the center of the solar system.
Check out this page for some nifty things you can build that may work on ion-propulsion. I thought it was a hoax at first, but my friend convinced me to build it in high-school, and the thing really did work. Of course, the efficiency was terrible. We were using an old monitor as a 20,000 volt power source, so power dissipation was probably pretty high. That was enough to lift the 2 gram device and 1 gram of payload.
A deep unwavering belief is a sure sign you're missing something...
ok, this is finally retarded enough. Rockets do not push against the air, they do not push against the "aether." Hell, they don't even push against the launching pad when they are on the ground.
Rocket exhaust (the flames, etc.) provide a force, yes, but THEY PUSH AGAINST THE ROCKET.
If you are standing on ice (wearing skates) and you throw a bowling ball away from you, you will slide in the opposite direction. The bowling ball doesn't need to hit anything for you to move.
...probe Uranus?
For ever action their is an equal and opposite reaction
I'm sorry, but that dosen't explain the curry from my local Chinese restaurant. The reaction is way bigger than the action. Perhaps they should have powered SMART-1 using that.
The point of ion drive is that it has waaaay higher efficiency than chemical rockets. Momentum is mass times velocity, so by pumping up the velocity you can correspondingly reduce the mass. That's what Ion drive does. It spits out atoms at ridiculous speeds.
Consider a chemical rocket. It very quickly gets you up to speed, but after that you just coast.
Now consider a drive that has, say, only 1/100th as much acceleration, but can run 10000 times longer. It'll take a long time to use up that fuel, but when you're done you will be going 100 times faster than the chemical rocket.
Obviously Ion drive is only useful once you're already in orbit, but if time is not an issue it's hard to beat.
Yeah, That dammed Ariane 4 rocket was only the most successful, accurate, reliable launcher ever.
Nasty horrid Europeans.
Sure Ariane 5 has had some teething troubles but don't mock the Europeans, they are the ones who made space commercial. Ariane is much more reliable than the Delta or Atlas Centaur launchers the US uses and whilst the shuttle is quite reliable, it's a ridiculously expensive way to put a commercial satellite in space.
Troc's dubious podcast and blog: http://www.trocnet.net
You're russian history is incorrect. They have had several mishaps. The ones that I can think of off the top of my head are Soyuz 1 and Soyuz 11. They have probably had somewhere between 150-200 manned launches. We'll hav change your definition of "launch mishap" to "the rocket went up but the people didn't come down alive".
We have had two accidents in our space program (3 if you count Apollo I, but in the above definition, it doesn't count)
The Russians do more launches than we do. In the past, they've done more manned launches than we did. Since the past 5 years, I'd say that we've probably done about the same number of manned launches.
This one is more reputable, I believe credited to Arthur C. Clarke.
...
It was a short story about an Earth-to-Moon (orbit-to-orbit) space race, in the spirit of the Kremer prize. The spacecraft were propelled by ion engines, which were energized by Whimshurst-type machines, which were powered by
bicycles.
The racers pedaled their way to the moon, the pedals effectively powering the ion engines that drove them. The race took several days, with the right stuff added in for absurd athletics, rest breaks, minimal life-support, race security, etc.
No doubt someone here will do the math that I never bothered trying to do. One of these days, maybe I will.
The living have better things to do than to continue hating the dead.
Sorry for that pun, but..
One point worth making - chemical rockets are getting close to the limits of thier possible efficiency. In contrast Ion engines are in their infancy. The main theoretic limit is that particles cannot be expelled faster than light. You could see very big leaps in engine power in the future..
"You lied to me! There is a Swansea!"
Hey guys, this stuff isn't just dumbass. A considerable amount of thought and understanding had to go into making it look that retarded.
In short, it's a troll. A real troll at that, not the pseudo trolls we usually see around here.
Not exactly the best troll I've ever seen, but in a way it's nice to see a Slashdoter make the effort to at least try to uphold the old traditions.
KFG
I spent a lot of time studying this technology while I was working towards my Bachelor's Degree. Okay, let's get some facts straight, for those of you without a degree in Mathematics or Physics:
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1) Ion Propulsion is NOT new technology. The Russians and German's have been experimenting with Ion Propulsion since the early 1950's. NASA is actually a late comer to the game, although the first with a completed ion propulsion engine.
2) Ion Propulsion do not work in an environment with an atmosphere. An ion engine does not have enough force to lift a sheet of paper more than a few inches.
3) An Ion Engine is very simple in design. For a simple explanation, an inert gas is ionized and injected into a chamber with an opening on one end. The opening has a magnetized torid ring around it. Using the right hand rule (make a fist, stick your thumb out like you are hitchhiking...your thumb is the direction of the electric current, your fingers are curled in the direction of magnetic field flow) you create an electrical flow around the metal torid ring. The resulting magnetic field 'pulls' the ions through the ring, resulting in propulsion.
4) The reason for slow inital acceleration is because the force of the ions passing through the ring is very small, but the velocity of the ions is very high. So, since there is no friction or other losses in space, after a period of time the velocity of the ions leaving the ring increases the velocity of the engine. After a matter of days the engine can be travelling at 10-30,000MPH.
For more information and history on Ion Propulsion engines you can go to the following websites:
http://science.nasa.gov/newhome/headlines/prop0
http://www.grc.nasa.gov/WWW/PAO/ds1.htm
http://space-power.grc.nasa.gov/ppo/projects/ns
...guide to the galaxy. Obviously this maneuver is very unnatural for all space vehicles, but it looks so cool rich people will surely want to have stuff that does that implemented in their spaceships. Just for showoff, no matter how inefficient and ridiculous that would seem :)
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
"Dark Sith" should that be moderated redundent? Or are there happy-go-lucky-smiley-face-Siths I'm unaware of?
heh.
The Kruger Dunning explains most post on
I hate those self-important A-holes who have those xenon propulsion systems. It seems like every night that I go for a short trip in low earth orbit, at least one schmuck has to fly by with those damned things turned on. How am I supposed to see where I'm going when I'm being blinded by the obnoxious blue glare that they spew? If they're the only ones who can see anything, it's not making things any safer overall.
I swear, I'm going to start flashing these jokers with my laser range finder if they don't get more considerate and stop using those damned xenon units in congested orbits.
if your '71 chevy truck is slow, you just put in a bigger engine right?! so how about a bigger ION drive. and a small nucleur reactor.
i suppose you do lose some efficiency by carrying your own fuel, but nuclear power is far more efficient than solar power right now.
with larger ION drives, or more small ION drives, and enough power from the reactor, this may be able to compete with a rocket engine for inter-solarsystem travel.
but then again, id rather have laser,mazer, or phaser cannons. I'll travel really really slowly if I have a really big gun!
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another advantage would be less vibration during accelleration. Imageing sending a team to Alpha Centauri using standard rockets. They would have to burn for 3 solid months to accellerate and the same to decellerate. 3 months is a long time to be strapped to a chair.
this solves the lack of gravity problem as well. Just accellerate at a rate the would be near 1G or at some acceptable level of force, then spin the ship around and do the same thing for decelleration. This way you would have artificial gravity for a good portion of the trip. I can't imagine the side effects of a couple of years is zero G, and what happens when the team trys to go to the plannet with no muscles built up for planetside life.
Alpha Centauri is something like 5,644,944,000 kilometers away, this is most likely a 5-10 year trip. Yes, artificial gravity would be good.
Also, the waste material from the reactor could be used as the actualy propellant(maybee, IANORS(I am Not a Rocket Scientist) and then you wouldn't have to store it, you could just eject it out the back of the craft.
Rockets use the same priciple that ion propulsion uses, the law of action and reaction (one of Newton's Laws, can't remember which one off the top of my head). Basically matter is accellerated out the back of the engine (by chemical means in the chemical rocket engine, and by using electro-magnetic forces in the ion propulsion engine). This accelleration causes causes a force to be placed on the engine that is equal to, but oppisite in direction, to the force accellerating the matter.
All means of propulsion -on Earth and in Space- use Newton's third law.
In practical terms, the difference is that Ion engines use energy from the sun, to accellerate small portions of matter (ions) over a long period of time.
Rockets use chemical energy to throw out matter, typically violently for a short period of time.
For these reasons Ion engines are predicted a bright future for travel over long distances (to the moon is unusually short in this context), there efficient use of energy wins out in the long run.
However, it seems unlikely that they could be used for lifting things into orbit; then you need to quickly accelerate to high speeds and get out of the athmosphere. Ion Engines are probably not suitable for chasing X-Wings around the Death Star either for that matter.
Tor
This isn't the first time an ion engine has been used in space. NASA's Deep Space 1 probe toured the solar system for over 3 years with an ion engine. This probe isn't very well known, since it was just a test bed. But in the end it made some history by performing the closest encounter ever with a comet.
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Luck is just skill you didn't know you had.
In more than 35 years of spaceflight the Russians have had something like 4 fatalities, and 3 (?) accidents (including one where the crew survived a booster failure in mid-flight - the stage didn't separate). In comparison to the U.S. record this is remarkably good. They have also flown more people for longer periods of time.
Since the past 5 years, I'd say that we've probably done about the same number of manned launches.
The same number of launches as the U.S., with a total budget of something like 200 million dollars, a factor of 30 less money. That's pretty impressive. The simple turth is that the U.S. is a second-rate space power.
Human genome = 3 billion base pairs = 6 GBit. Windows + Office = 20 Gbit. Which is more impressive?
Deep space one and many communications satellites already use them.
They dont really make sense as backup as you have to have two completely separate systems to support them (propellant feed, power, etc). Thats a lot of mass for something that may be nothing more than backup.
They make perfect sense for unmanned missions. Theres typically no hurry to get where youre going, and the mass benefits are large.
They can be used on manned missions, the crew would simply rendezvous with the craft in high Earth orbit rather than being aboard for the entire escape spiral from Earth.
"Open the pod by doors, Hal" > "I'm afraid I can't do that, Dave" sudo "Open the pod bay doors, Hal" > alright
In other words: the maximum push of ion engine is only limited by the energy source and technical competence in high-voltage engineering, not by any inherent flaw in the technology. An ion engine is perfectly capable of lifting from Earth surface (or chasing X-Wings) assuming you have a suitable power source (nuclear reactor, most likely) and power trasporting/transforming equipment (wires and a voltage converter).
This is very true, but
1 All ion engines currently discussed use solar cells as their energy source. The whole point is that you only bring matter, not the energy source to accelerate it.
2 If you are prepared to bring an energy source as well, then you are basically back to the rocket case. Sure, you can bring a nuclear reactor, use heated atoms to drive a turbine and generate electricity, and then use the electricity to accellerate ions. But then it is more efficient to use your reactor to throw out particles directly, skipping the step of turbines and electricity generation. Btw researchers are working on such nuclear rocket systems. These would be much more efficient than anything we have today, but also politically problematic to say the least.
Tor
If you know not Fusial Thrust what is, no Jedi are you! Comes from the Force it does, very strong power, Dark Side it leads to can.
It may help to think of any rocket-type (and ion, too) propulsion based system like this:
Basically, the center of mass of a fueled up rocket does not change. If you had a rocket at a dead stop and started a burn, you'd throw as much stuff behind you as your displacement was forward. Hence in a simplified 1D rocket model (which is actually pretty close to correct, diffusion is actually pretty minimal) your center of mass never moves.
Arguably, you could say this means that the entire rocket array (fuel and all) never actually moves: just spreads itself out, with the useful "stuff" at one end of the displacement.
My favorite proposal from the near past was the magnetic bubble. Create a large static magnetic field - a simple dipole will do- in space, and then fill it up with plasma. The plasma causes it to expand greatly in size, which is important because the dipole field decays as r^-3. It would act much like the Earth's own magnetosphere with a shock upwind and a long tail. But unlike at Earth, this magnetic bubble can be oriented in any direction. It has been compared to a balloon in operation.
"I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
But then it is more efficient to use your reactor to throw out particles directly, skipping the step of turbines and electricity generation.
I am not a rocket scientist, but it appears that you've oversimplified the problem.
Can't use the nuclear reaction directly while in the atmosphere, too much fallout. That's why we use chemical rockets in the first place (well, that and the fact that nuclear rockets haven't even been built yet). Suppose we could stick a small nuclear reactor and an engine on a single box and launch it into orbit. That eliminates the space shuttle's current booster system and massive fuel tank.
The ideal earth to moon shuttle should be able to take off from the surface of either body and fly all the way to the surface of the other body, and hopefully have enough reaction mass left to return (not likely, I suppose). This shuttle can't have a bunch of boosters and big fuel tanks that it drops into orbit on its way. When you have to shed 90% of your weight just to make it all the way up, you're operating very inefficiently.
In my opinion, any engine that has the potential to take us from surface to surface earth to moon without all the clumsy boosters is an engine that should be thoroughly pursued.
Then we can build, in orbit around the moon (or somewhere else in the vicinity) the big interplanetary vessels with the nuclear rockets.
Like what I said? You might like my music
so what you're saying is that NASA is the Microsoft of the space industry, and Russia, Linux...
Yes, I damned well belive the Moon landings happened. I've done chemical analysis on the rocks; I've met some of the astronauts; my best friends dad helped build the LEM at Grumman. So yeah, they happened.
I'm not sure what annoys me more: idiots like you who don't think it ever happened, or the idiots in the White House, Congress and the public who didn't think it's important enough to keep funding.
I guess we're living in a society where our greatest achievements lie behind us, rather than ahead of us. In that situation I shouldn't be surprised that there are fools like you who try to make themselves feel better by claiming the achievements of the past never happened.
Human genome = 3 billion base pairs = 6 GBit. Windows + Office = 20 Gbit. Which is more impressive?