New Engine Raises Possibility of Cheap Travel To the Moon 100
shreshtha writes with this intriguing bit from The Daily Mail: "A tiny satellite thruster which can journey to the Moon on just a tenth of a litre of fuel could usher in a new low-cost space age, its creators hope. The mini-motor weights just a few hundred grams and runs on an ionic chemical compound, using electricity to expel ions and generate thrust. The tiny motor isn't built to blast satellites into orbit — instead, it's to help spacecraft manouevre once they're in space, which previously required bulky, expensive engines."
Sweet! (Score:5, Funny)
To whom shall I write the check as I securely invest my life savings?
Re:Sweet! (Score:4, Informative)
No joke, especially considering this is from the Daily Mail. I mean come on, why would they even think anyone would get real news from such a place.
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Read this site first. (Score:5, Informative)
http://www.projectrho.com/rocket/enginelist.php#id--Ion [projectrho.com]
It's a great site which details (with lots of math) the various problems with space travel.
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Great stuff, thanks. Turns out I had it bookmarked from two years ago and had forgotten about it. Some of the engine designs are amazing, and the commentary is definitely worth reading.
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The problem with space travel has always been the depth of the gravitational well, the immense size and cost of life support for us big meat robots. Space travel to the moon was just John F. Kennedy's way of developing rocket that could put a nuclear warhead the size of greyhound bus in Moscow. "I am for the stars, but sometimes I hit London" ~Werner Von Braun
We are closer to the stone age than we are to real space travel, don't get your hopes up. The only, and I repeat only, viable space exploration so far
Re:Sweet! (Score:5, Interesting)
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Speed (Score:4, Insightful)
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I was under the impression that fuel to get to the moon isn't a major issue, if you can launch a few years before you need to be there. There's (almost) no friction to stop you...
Actually, it only takes six months, according to TFA. And you and your life support, food, waste management, etc. must weigh less than a kilogram.
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So basically, Anorexics make perfect astronauts.
Re:Speed (Score:5, Funny)
Anorexic hamsters, possibly. Even Kate Moss weighed more than a kilogram.
(You must be American and unfamiliar with SI units.)
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Kate Moss is not dead (as of Mar 31, 2012).
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(You must be American and unfamiliar with SI units.)
actually a pound weighs less than a kilogram, but only on the surface of the earth because pound is not really a measure of mass, although retards who get their physics from supermarket scales are welcome to disagree.
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I conclude that you must be a retard and unfamiliar with SI units.
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So basically, Anorexics make perfect astronauts.
Or double amputees. Arms are useful in space. Legs are just excess mass that take up space and get in way.
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Guess the space mice win this race again.
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If we're not careful, he'll do something like reboot the Teenage Mutant Ninja Turtles with the premise that they are aliens.
From Where? (Score:4, Informative)
Seriously, I can travel to the Moon with no fuel if I start in the right position with the right momentum. TFA doesn't tell us much unless the secrets are hidden in the video I'm blocking on the bottom of the page.
Re:From Where? (Score:5, Insightful)
Seriously, I can travel to the Moon with no fuel if I start in the right position with the right momentum. TFA doesn't tell us much unless the secrets are hidden in the video I'm blocking on the bottom of the page.
Sorry to self-reply, but:
Can we stop having summaries posted where the only link goes to the Daily Mail? Every human should be disgusted that our species can produce something as wretched and pathetic as that hive of stubborn ignorance.
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It could be worse. We could be linking to digg or reddit posts.
Also, the video says it can get to the moon in 6 months. They don't mention what the initial orbit is like, so I would hope they mean that they can make it from an arbitrary orbit to the moon in that time.
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It could be worse. We could be linking to digg or reddit posts.
Also, the video says it can get to the moon in 6 months. They don't mention what the initial orbit is like, so I would hope they mean that they can make it from an arbitrary orbit to the moon in that time.
Also glossed over is the earth-to-orbit costs. Once you ignore 95% (number pulled from ass) of the cost everything sounds cheap.
Grabbing and tossing spent satellites back to earth is also nonsense. At most, you only need to slow them down by some calculated amount, but then you also have to disengage, turn around, and thrust your way back to a safe orbit to pursue the next piece of space junk. You will need years of "fuel" (mass to eject) to make a dent in the junk pile orbiting earth, and an enormous ban
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digg or reddit aren't even close in vileness to the mail. the mail is a pustulent discharge from the thin-lipped mouth of its editor
Re:From Where? (Score:5, Funny)
Maybe we can try 'right position and right momentum' with Timothy'. A good swift kick in the kiester would do him some good....
Re:From Where? (Score:5, Informative)
The propulsion system emits ions at high speed (40 km/s) and is thus very efficient at converting propellant mass to satellite momentum. Thrust is low, but given time, ver lge orbit chanegs are possible. for example, in order to reach lunar orbit from low-Earth orbit, a 3-kg nanosatellite with our motor would travel for about 2 years and consume about 500 grams of fuel" - Herb Shea
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so what... are you some kind of rocket scientist?
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Discussuon on a talk show:
Interviewer: "Now Dr., can you explain what the obstacles are to a manned mission are?
Scientist: "Well, the first problem is getting your vehicle out into Earth orbit. Then you have to get your trajectory right in order to reach Mars orbit. Then you can send down an exploration vehicle. The main problems are carrying enough food and water as well as waste disposal. Radiation is another problem. But all of these problems have solutions developed for terrestrial exploration."
Intervie
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Wow. Just... wow. At first I thought the reason this was over-hyped was because it was in the Daily Fail. But no. You actually have it on your own press release.
You, sir, are a charlatan. Perhaps you can get to the moon on a few "drops" (nice non-defined quantity there) of fuel, but you have to start in Earth orbit - ie in terms of energy 99% OF THE WAY THERE.
If you had any decency at all, you would at least insist that your own headlines be something along the lines of "From Earth's Orbit to the Moon on 50
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This device sounds basically like a miniaturized ion drive. Is that correct? If so, how does its efficiency compare with ion drives in use on exploration spacecraft?
Either way, I'm sure Scotty would be impressed with your work [memory-alpha.org] :)
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Indeed, in the right position, adequate life support, with a fart loud enough (and by loud I mean powerful... we all know there is > no sound in space)... you could get to the moon in no time :p
Wow (Score:5, Funny)
Who would have guessed this got posted by Timothy!
Someone's reinvented the ion engine (Score:4, Interesting)
If this were news for nerds, maybe someone would have researched this before posting [wikipedia.org]?
Forget it, Jake. It's Slashdot.
Re:Someone's reinvented the ion engine (Score:5, Interesting)
I do not think that the news is that they reinvented it, and seriously everyone on /. knows of the about ion-engines so there is little point in even mentioning it. But that here is a practical use of that engine that works better then anything else we are currently using.
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Sure, it "works better" in that it uses less fuel... but it doesn't "work better: in the sense that it now takes weeks to transport a millionth of the mass that more conventional methods can.
As I've said before, capabilities matter. A motor scooter that can't top 35mph gets much higher fuel mileage than a semi... but only a fool would confuse the two.
Misleading (Score:5, Informative)
The new thruster has nothing to do with getting to the moon or even getting into space. It's a way for a small satellite to maneuver once it is in orbit. It could possibly be used for getting into lunar orbit from low earth orbit, but its intended purpose right now is to help clean up debris.
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How is this new? (Score:1)
Re:How is this new? (Score:4, Interesting)
Well over a decade.
The fundamental problem with ion thrusters (as a general class) is that you trade power use for fuel use.
Yes, they may use lots less fuel.
http://en.wikipedia.org/wiki/Specific_impulse#Examples [wikipedia.org] - for example.
An advanced ion thruster may use nearly 1/50th of the fuel of a conventional rocket engine.
But, it needs 50 times the power to do this.
So, to replace a conventional rocket engine burning a kilo of fuel a second, and producing a thrust of perhaps 500kg, with no electrical requirements, you need about 20 grams of fuel a second, and around 450 megawatts of power.
Needless to say - for many applications, the power plant ends up heavier than the engine it's replacing.
It only works in very low thrust applications.
The low thrust also brings other problems.
For example, around the earth is a belt of charged particles.
Ascending through these on conventional rockets is not a problem. You do it so rapidly.
With ion engines, you need to slowly spiral out (due to being power limited), and your whole craft gets highly irradiated.
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Well - yes, and no.
The fundamental problem with microwaves is - they're microwaves. ... - they undergo diffraction.
They are just another sort of radio, and like all radio waves, and light, and
This limits how much you can focus them.
A 'small' transmitter antenna of say 1km, with microwaves of about 10cm wavelength, will have a beamwidth of about:
1.22*.1m / 1000m.
This is a beam which spreads about one part in ten thousand.
After 10000km, the beam will be one kilometer in diameter. At the distance of the moon -
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Re:How is this new? (Score:5, Informative)
I'm biased, 'cause I work on this!
http://lmts.epfl.ch/microthust [lmts.epfl.ch]
- Herb Shea
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Parent link is bad. Try this - (Score:5, Informative)
Parent link is bad. Try this:
http://lmts.epfl.ch/microthrust [lmts.epfl.ch]
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Is there any particular reason why you use a colloid compound? Is it because it's heavier (more Daltons) and yet cheaper than Xenon atoms?
Also, if you turn your drive on for a year, wouldn't the extractor grid electrode get gummed up or "poisoned" with the molecules that are too lazy to be accelerated "to infinity and beyond" by the secon
Please clarify "fuel" vs. "propellant" (Score:1)
It still seems like you're conflating "fuel" and "propellant". You're using 100ml of propellant, but accelerating it using an energy source external to that 200g budget, right?
This is still a big deal, since even small satellites can deploy significant solar panels, but it seems like you'll avoid a lot of arguments and criticism by clarifying this point up front.
And, as another poster said, thanks for participating in this discussion!
Fortune Knows It's BS (Score:2)
The fortune at the bottom of the page in which I'm posting says:
But evidently Timothy doesn't read to the bottom of the page, either.
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Sorry, but no mass means just traveling at light speed. Faster-than-light needs imaginary mass.
The expensive part (Score:5, Interesting)
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Not much. The elevator itself is actually not in orbit, so anything detaching from it immediately starts falling down, accumulates some funny velocity (it's falling down in vacuum, so it won't reach a terminal velocity as when falling in atmosphere) and fiercely burns up on reentry.
The Earth-side construction side might be damaged by the low-altitude debris but the high altitude part of the elevator (which makes up for about ~99% of it) should burn-up safely in the atmosphere due to high accumulated velocity.
On the other hand - blowing up a space elevator on a body with no or low atmosphere - you'll probably get a nice 1:1 globe with a finely engraved equator line. :)
I wasn't talking about the orbital pieces. I really don't know what would happen for certain to those. Large parts of it might just go flying off becoming a huge debris problem in orbit (like we don't have that problem already as well). I'm talking about the miles of construction in the atmosphere getting up there. That stuff isn't going to burn up and is going to land on someone. Just look at what happened when the twin towers came down. Now imagine 60 miles of that stuff coming down.
Fly me to the moon (Score:1)
Microsats (Score:2)
As others have noted, this is only "new" in the sense that they've made a prototype of a particular design. There's no new technology from what I can see. Ion engines have always been well suited for any mission that can be performed with tiny amounts of thrust over a long period, and it's not surprising you can plot a very-low-thrust course that can get you to the moon if you have plenty of time.
I still have my doubts about microsatellites. There are fixed costs to launching satellites regardless of si
Just got (Score:1)
Deja'Vu
http://science.slashdot.org/story/06/01/15/0149227/new-ion-engine-being-tested [slashdot.org]
Ion engines are already pretty efficient... (Score:3, Informative)
My god, it's full of dumb! (Score:1)
Ion thrusters are not new Have been used for decades to do attitude correction on satellites and have been the primary propulsion for a couple probes to the outer edge of the solar system. http://en.wikipedia.org/wiki/Deep_Space_1
The story at the link asks if this is available for cars. Yes! it is! and your car will travel just as fast as if you got out and blew on the back of it!
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The story at the link asks if this is available for cars. Yes! it is! and your car will travel just as fast as if you got out and blew on the back of it!
That's the dumbest thing i've ever heard. You don't need to get out of the car, you can just stick your head out the window and blow backwards. Just remember to turn your head 180 degrees to inhale. And do the opposite if you want to slow down.
Imagine a cluster of these thrusters... (Score:2)
Getting into orbit (Score:2)
Is biggest expense of fuel i bet.
And when rocket fuel is just $2.00/gallon (Score:2)
We can build our Moon Base for super-cheap with exported Mexican labor!
NEWT!!! NEWT!!! NEWT!!! NEWT!!! NEWT!!! NEWT!!!
Unrealistic (Score:2)
How big would this thing need to be to get a human being to the moon in under a week?
April 1 (Score:2)
According to slashdot this article was posted April 1... I'm not buying it.
things in space have always been relatively cheap (Score:2)
oh great... (Score:1)
But seriously, what is there to do with satellites around the moon? Certainly something less useful than around Earth. Still neat though.
Ionic chemical compound... (Score:2)
This sounds very similar to Digital Solid State Propulsion [dsspropulsion.com], a states-side company that has been testing electrically-fired chemical microthrusters for at least the last several years. The DSSP thrusters (at least the ones I've seen so far) ranged from about the size of a .22 shell casing to an "AA" battery, and produce a controlled jet of ionized gas when electricity is applied (a gelled fuel inside is slowly consumed in the process). They're intended for propulsion and micropositioning (e.g. long-term stat