Ion Engine Propels Probe to Moon 330
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?"
Tie fighters (Score:5, Funny)
Yes, I do know why ion engines are a good idea. Just leave Star Wars out of this.
Re:Tie fighters (Score:2, Informative)
TIE (Score:5, Funny)
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.
Re:TIE (Score:2)
Re:TIE (Score:2)
In Soviet Russia, early cosmonauts didn't wear pressure suites to display the superiority of their space program. They needlessly lost people due to that practice, and have changed to using pressure suites as result.
Also, remember the TIE figter pilots were clones, so they would wear a mask even if they we
Re:TIE (Score:2)
I don't remember where they said they were clones...Unless you are just assuming that after the events of "Attack of the Clones"
You didn't see attack of the clones, did you? (Score:2)
Also, the books talk about Storm Troopers being grown instead of recruited.
Re:You didn't see attack of the clones, did you? (Score:2)
Still, just because there were clones during the founding the empire in AotC doesn't mean that all stormtroopers and TIE pilots in ANH were clones.
Re:You didn't see attack of the clones, did you? (Score:2)
Then there's the phrase, "Aren't you a little short for a stormtrooper?"
Re:You didn't see attack of the clones, did you? (Score:2)
In fact, I recall the 'Storm trooper training planet' getting blown up.. Jedi Academy trilogy?
Re:TIE (Score:2)
Re:TIE (Score:5, Funny)
geez, the people on slashdot these days!
Re:TIE (Score:2)
We don't need no stinkin' micro-meteor deflection systems, no how!
Re:TIE (Score:3, Funny)
Obligatory. . . (Score:5, Funny)
(sigh) Then the Emperor has already won.
Ion drive is cool, but... (Score:2, Interesting)
Hopefully they can perfect the ion drive, however through this to increase the speed and payload capacity. Then we might have something really cool... (u
Re:Ion drive is cool, but... (Score:3, Insightful)
Re:Ion drive is cool, but... (Score:5, Informative)
In the future missions you will see these sorts of drives giving much faster flight times to Mercury, Mars, Jupiter, Saturn.. - although for the outer system you may need nuclear instead of solar power.
Yes both this and parent are dupes from previous thread..
Re:Ion drive is cool, but... (Score:5, Insightful)
This project cost just 100E6 Euros. That's about one quarter the cost of a single shuttle launch, never mind the astronomical costs of each Apollo mission.
Personally I'd much rather see 4 new projects like this and one fewer shuttle launch.
Re:Ion drive is cool, but... (Score:3, Informative)
Once you start tying ion propulsion to a nuclear power source, you start being able to achieve higher thrust levels. SMART only uses a little over 1kW of power.
Its very practical.
Ion propulsion can take longer than chemical (although this is not always the case) but it has a much higher specific impulse, and therefore a much lower propellant mass fraction. That means you can get more mass to a destination given the same launch m
Re:Ion drive is cool, but... (Score:5, Funny)
That's what you think. Ooops, I've said too much already.
Re:Ion drive is cool, but... (Score:2)
elevator (Score:5, Funny)
ionize xenon atoms? (Score:2)
Re:ionize xenon atoms? (Score:3, Informative)
Re:ionize xenon atoms? (Score:2, Insightful)
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.
Yes, Alice, that's right... (Score:3, Funny)
Friction (Score:4, Insightful)
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.
Re:Friction (Score:2)
You just need to have enough mass you can eject in some direction. That is called propulsion. Just collect enough light, and you will be doing well.
Re:Friction (Score:2)
You haven't read Hitchiker's (Score:3, Funny)
Re:Friction (Score:2)
What if someone invented a 'Gravity reflector' that replys gravity? then you could us the gravity as the force your reacting to in order to move like an aircraft.
Sure, It sounds lame from me on slashdot, but if any greate Sci-Fi author had the same idea, you would think it was the coolest idea since cat doors.
Re:Friction (Score:2)
Silly DUPLICATES (Score:2)
Yo Grark
Canadian Bred with American Buttering...American Buttering....American Buttering...
We Like The Moon... (Score:3, Insightful)
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
Finally!! (Score:2)
Re:We Like The Moon... (Score:2, Funny)
Build your own ion drive (Score:3, Interesting)
Re:Build your own ion drive (Score:2)
Also, thrust (force) isn't the same as acceleration. Say you're getting 11 m/s^2 of acceleration in an upwards direction. For a 3 gram lifter, this equates to a thrust of only 0.033 newtons of force. That's only 0.0074 pounds of thrust, or about 1/7 t
Dupe or extreme interest (Score:2)
Could such engines... (Score:2, Funny)
Other science fiction reference... (Score:5, Interesting)
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.
Re:Other science fiction reference... (Score:3, Informative)
No doubt someone here will do the math that I never bothered trying to do.
I ran some numbers and the feasibility depends pretty much entirely on the weght of the spacecraft.
If we assume a 250,000 mile race, completed in 10 days, (with no resting, since that complicates things more than I want to deal with right now), that means you need a constant acceleration of 0.11 cm/s^2. Not very much, right? Not if you're just accelerating your own weight. In fact, if *all* you had to push was, say, 60kg, it'd
This is something I will be keeping my Ion.. (Score:3, Insightful)
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..
Re:This is something I will be keeping my Ion.. (Score:2)
Re:This is something I will be keeping my Ion.. (Score:2, Interesting)
Re:This is something I will be keeping my Ion.. (Score:2)
No, it isn't. You just have to carry more fuel if you want to exceed your exhaust velocity. This is basic physics. Review the rocket equation. Current rockets routinely exceed their exhaust velocity by several times. (NB - this applies to rockets carrying -- and hence accelerating -- their fuel. A scramjet has a problem with this -- which is why scramjets are really a silly idea for Earth-to-orbi
Ion Propulsion (Score:5, Informative)
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
Re:Ion Propulsion (Score:2)
Re:Ion Propulsion (Score:5, Informative)
First, this probe was from the European Space Agency, not NASA. NASA doesn't own Europe, as far as I know, and can't even afford to replace the bearings on the ancient platforms that carry the Space Shuttles to the launch pad.
Second, NASA's Ion engine (on Deep Space 1) failed in lab tests, and then failed in space. NASA had to "shake" the probe using the gas-based manoevering jets, using up valuable fuel. The probe was a success in the end, but more by luck than design.
Re:Ion Propulsion (Score:5, Funny)
Don't worry, citizen, soon we'll liberate you too!
Re:Ion Propulsion (Score:4, Informative)
Actually, what you describe there sounds like a Hall effect thruster. Not all ion drives are Hall thrusters.
DS1's ion engine used charged grids rather than a metal toroid to achieve the acceleration of the ions.
In addition to Hall effect thrusters and grid-based ion engines, there are also arcjets, resistojets, and the ever-sexy-but-a-few-years-off magneto-plasma-dynamic thrusters.
Re:Ion Propulsion (Score:2)
Tuesday is the important day (Score:2)
Re: Friction (Score:5, Interesting)
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.
AFAIK, space isn't a perfect vacuum, there is matter in space, just that it's concentrations are extraordinarily low. You'd need either a very large control surface, or some method of increasing friction over what limited matter there is. Why do we use brake pads on a car and not say, bars of moist Ivory? Same reason.
Also, there is also free energy in space...particularly in a solar system. I'm not sure if light energy is believed to be particulate this week, but is it possible that photons or other forms of high frequenty energy could be used as a repuslive force? There's still quite a bit we don't understand about this stuff, and though at this point it's still probably the rhelm of science fiction, It's not impossible. Remember, there are no fictionless surfaces, no perfect vacuums, no perfect superconductors, only asymptoticly approaching approximations.
-Chris
PS - I apologize in advance for the above average number of typos and possible flaws in knowledge and logic....I'm on an iMac today ;-)
Re: Friction (Score:2, Funny)
IIRC, those big panels (Score:2)
Xenon sucks (Score:5, Funny)
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.
thoughts (Score:4, Interesting)
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!
--
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.
Re:thoughts (Score:4, Informative)
In Kilometers this is:
41,220,846,106,794
So you calculation is a bit off in the time scale.
To reach it in 10 years you would have to be going roughly half the speed of light or 150,000,000 meters per second
Not the first time an ion engine has been used... (Score:3, Informative)
The Moon again, finally! (Score:2)
NASA still seems very reluctant to send anything, but they are being forced to by a recent review of solar system p
TIE Fighters are FAR OFF!!! (Score:2)
For the sake of physics (Score:2, Interesting)
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 an
Re:Ooh, IONs (Score:3, Informative)
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.
Re:Ooh, IONs (Score:4, Funny)
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.
Re:Ooh, IONs (Score:5, Funny)
Re:Ooh, IONs (Score:5, Informative)
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 [nasa.gov] used ion propulsion.
Re:Ooh, IONs (Score:5, Informative)
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
Re:Ooh, IONs (Score:3, Informative)
This is very true, but
1 All ion engines currently discussed use solar cells as their ene
Re:Ooh, IONs (Score:3, Insightful)
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 singl
Re:Ooh, IONs (Score:2)
Re:Ooh, IONs (Score:3, Funny)
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 electr
Re:Ooh, IONs (Score:2, Informative)
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.
Re:Ooh, IONs (Score:2)
Re:Ooh, IONs (Score:2)
Any respectable scientist knows that space travel is impossible anyway, that NASA never put any men on the moon, and that any satellite in orbit that you might THINK you see is really swamp gas, reflected off of Venus...
And as for my sibling posters in this subthread, you might wanna turn up the sensayumor knob in yer forebrain.
Re:Ooh, IONs (Score:2, Funny)
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
Re:Ooh, IONs (Score:3, Informative)
Re:Ooh, IONs (Score:2)
Anyone care for a Reactionless Thruster [arxiv.org]?
Re:Ooh, IONs (Score:2)
people are talking about is imagine firing a gun.
It "kicks".
The expanding gasses push the bullet out one end, sure, but they also push the
whole gun back against your shoulder. If your shoulder weren't there . .
Another example would be trying to hold onto a fire hose. If you've never had the opportunity just rent Roxanne. Then you can go down to your local Kaybee (or other) toy store and buy a cheap little plastic thing that put
Re:Ooh, IONs (Score:2)
Re:Ooh, IONs (Score:2)
You wouldn't happen to work for the New York Times, would you?
Re:Ooh, IONs (Score:2)
(note that the above contains intentional grammatical no-nos, designed to indicate my overwhelming potential as a New York Times editor.)
Re:Ooh, IONs (Score:3, Interesting)
My favorite proposal from the near past was the magnetic bubble [washington.edu]. 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
Re:Ooh, IONs (Score:5, Informative)
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.
Re:Its about time. (Score:5, Insightful)
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.
Re:Its about time. (Score:5, Interesting)
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.
Re:Its about time. (Score:5, Interesting)
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.
Re:Its about time. (Score:2)
True, but the number of fatal accidents is about the same - NASA just had more people on each of the fatal voyages.
I don't think the numbers are large enough to reach any justifiable c
Re:Its about time. (Score:4, Insightful)
Re:Its about time. (Score:4, Interesting)
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.
Re:Its about time. (Score:2)
Also, if the 1000 lauch figure you state includes unmanned launches, I think that the US has them beat by a long shot... I'll have to look up some numbers, but I think you're mixing apples and oranges.
Re:Its about time. (Score:4, Insightful)
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.
Re:Its about time. (Score:2)
Re:ion engine limitations (Score:3, Informative)
Even better, if you are doing something like flying to Mars, an ion engine combined with a normal engine has a lot of potent
Re:ion engine limitations (Score:2, Interesting)
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 1/100t
This is NOT the first ion engine in use (Score:3, Informative)
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 or
Re:me? (Score:5, Funny)
heh.
Re:Fusial Thrust (Score:2)
Re:Fusial Thrust (Score:2)