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New Engine Raises Possibility of Cheap Travel To the Moon

timothy posted more than 2 years ago | from the how-many-altarian-dollars-though dept.

Space 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."

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100 comments

Sweet! (5, Funny)

Lije Baley (88936) | more than 2 years ago | (#39535449)

To whom shall I write the check as I securely invest my life savings?

Re:Sweet! (4, Informative)

Anonymous Coward | more than 2 years ago | (#39535571)

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.

Re:Sweet! (2)

EdZ (755139) | more than 2 years ago | (#39537161)

Well, it is the Daily Fail. It may have taken them over a century to report on the concept of the Ion Thruster, but at least a few of the facts in their story are actually correct (which is probably a new record for them).

Read this site first. (4, Informative)

khasim (1285) | more than 2 years ago | (#39535587)

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.

Re:Read this site first. (1)

kermidge (2221646) | more than 2 years ago | (#39538339)

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.

Re:Read this site first. (1)

Anonymous Coward | more than 2 years ago | (#39541313)

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, is robots and satellites. Launching slump shoulder sacks of guts like us meat robots inte outer spece is neither cost effective or viable. Once you leave the protective blanket of our atmosphere it is only a matter of time before one absorbs a toxic dose of radiation.

Re:Sweet! (5, Interesting)

tommasorepetti (2485820) | more than 2 years ago | (#39535805)

https://en.wikipedia.org/wiki/Deep_Space_1 [wikipedia.org] This is not exactly new... at all. NASA's ion engines have been in service for several years now. Also a tenth liter of fuel is also willfully misleading: the engines expell a liter of propellant but that is not fuel. It is just the expelled material whose momentum generates the forward thrust.

Re:Sweet! (2, Funny)

crutchy (1949900) | more than 2 years ago | (#39538427)

my car doesn't use fuel either... just material that when ignited in a mixture with oxygen generates an explosion inside a chamber with a piston that imposes a moment in a crankshaft and induces a reaction from the earth against the tire surfaces in such a way as to get me where i need to go with a bit of interaction via an orientation correction device inside the cabin. apparently there are 6 of these miraculous so called "cylinders" in my transportation machine! modern technology is just amazing isn't it?

Re:Sweet! (2)

wagnerrp (1305589) | more than 2 years ago | (#39538781)

You misunderstand. Your car is fueled by gasoline, which drives the pistons. This "new engine" is fueled by a nuclear reactor, or solar, or whatever, and the tenth liter of "fuel" is just inert reaction mass. There is no energy to be extracted from it, it's merely something to push off of.

Re:Sweet! (2)

tommasorepetti (2485820) | more than 2 years ago | (#39539457)

The difference is this: a rocket engine not only uses the oxygen/hyrdrogen mixture as the propellant (the steam that is being expelled from the rear) but also as a "fuel" i.e. that from which the whole process derives its energy. The ion engine is using an imposed electric field gradient to accelerate the charge particles (ions) of its propellant out into the vacuum of space and to move the probe foward. The energy for this is coming from a combination of solar panels and a battery. One other weird thing about these engines: the reason it takes six months is because it takes forever for these things to reach speed. 0 to 60 is something like a few days. If you leave them on for years (liike Deep Space 1), it will reach many tens of thousands of mph because these little particles have been contributing their momentum so consistently for such a long time. If Picard were at the helm of an ion-engine-powered vehicle there would be an awkward decade-long pause after he ordered the Enterprise to go to warp factor two...

Speed (3, Insightful)

Sarten-X (1102295) | more than 2 years ago | (#39535459)

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...

Re:Speed (1)

AliasMarlowe (1042386) | more than 2 years ago | (#39535521)

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.

Re:Speed (1)

wisnoskij (1206448) | more than 2 years ago | (#39535573)

So basically, Anorexics make perfect astronauts.

Re:Speed (4, Funny)

ColdWetDog (752185) | more than 2 years ago | (#39535693)

Anorexic hamsters, possibly. Even Kate Moss weighed more than a kilogram.

(You must be American and unfamiliar with SI units.)

Re:Speed (1)

davester666 (731373) | more than 2 years ago | (#39536217)

Kate Moss is not dead (as of Mar 31, 2012).

Re:Speed (1)

crutchy (1949900) | more than 2 years ago | (#39538453)

(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.

Re:Speed (0)

Anonymous Coward | more than 2 years ago | (#39539803)

and on what surface does a pound weigh more than a kilogram?

Re:Speed (1)

crutchy (1949900) | more than 2 years ago | (#39546811)

a pound is only comparable to kg on the surface of the earth, because everywhere else a pound is a force and kg must be multiplied by acceleration due to gravity to be comparable

Re:Speed (1)

fatphil (181876) | more than 2 years ago | (#39548841)

A pound is an SI unit of mass, being as it is an exact multiple of the approved SI unit of mass (the kilogram), according to, amongst others, the NIST. E.g. see http://physics.nist.gov/Pubs/SP811/appenB9.html#MASSinertia

I conclude that you must be a retard and unfamiliar with SI units.

Re:Speed (1)

crutchy (1949900) | more than 2 years ago | (#39557337)

omg another nist dickhead. lucky for you nist only operates on the surface of the earth, or you'd be completely fucked

Re:Speed (2)

ShanghaiBill (739463) | more than 2 years ago | (#39536079)

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.

Re:Speed (0)

Anonymous Coward | more than 2 years ago | (#39536213)

Guess thats why Robonaught in the ISS has no legs. Arms are useful.

Re:Speed (0)

Anonymous Coward | more than 2 years ago | (#39555047)

Better: Quaddies!

Re:Speed (1)

mikael (484) | more than 2 years ago | (#39536451)

Guess the space mice win this race again.

Re:Speed (1)

crutchy (1949900) | more than 2 years ago | (#39538465)

NASA has been spending its budget on a developing a super race of monkey that will someday supersede humanity in space exploration. that's why they've achieved fuck all else since the moon race.

Re:Speed (1)

dlingman (1757250) | more than 2 years ago | (#39541457)

so - Smurfs in Space, directed by Michael Bay?

Re:Speed (1)

schroedingers_hat (2449186) | more than 2 years ago | (#39547013)

Don't give him ideas. We have to be careful about mentioning insane and stupid ways of ruining our childhood memories.
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? (3, Informative)

Colonel Korn (1258968) | more than 2 years ago | (#39535465)

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? (5, Insightful)

Colonel Korn (1258968) | more than 2 years ago | (#39535477)

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.

Re:From Where? (1)

Anonymous Coward | more than 2 years ago | (#39535597)

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.

Re:From Where? (1)

icebike (68054) | more than 2 years ago | (#39536297)

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 bank of computers to manage the whole operation.

With an international agreement that EVERY launch must plan to re-enter its own debris, AND carry one or more of these clean up bots into orbit this might be a workable long term plan, but not at $11 million apiece.

Re:From Where? (1)

shilly (142940) | more than 2 years ago | (#39536645)

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? (4, Funny)

ColdWetDog (752185) | more than 2 years ago | (#39535703)

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? (5, Informative)

hrshea (2599465) | more than 2 years ago | (#39535729)

As the lead author of the work, I'm happy to give you some more direct links EPFL press release: http://actu.epfl.ch/news/getting-to-the-moon-on-drops-of-fuel/ [actu.epfl.ch] MicroThrust consortium: http://www.microthrust.eu/ [microthrust.eu] EPFL research on micro propulsion: http://lmts.epfl.ch/microthrust [lmts.epfl.ch]

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

Re:From Where? (1)

Anonymous Coward | more than 2 years ago | (#39535821)

so what... are you some kind of rocket scientist?

Re:From Where? (1)

mikael (484) | more than 2 years ago | (#39536527)

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."

Interviewer: "So, it's not really rocket science, doing this exploration?"

Scientist: "Actually, it is rocket science!"

Re:From Where? (2, Insightful)

Anonymous Coward | more than 2 years ago | (#39535869)

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 500g of fuel" or some such, and make clear in the first sentence that you're talking about 3Kg satellites, not entire space shuttles, but instead you imply that I can fill up a half-liter of fuel in my ship here, bid farewell to Cape Canaveral, and be on the moon shortly.

This has really got to stop. Honest claims about genuine research are great, but this kind of overblown bullshit hurts all of science. When people find out that in fact you've just moved the goalposts so far that the goal you've achieved isn't anywhere near what you're advertising, they lose faith in all of us.

Re:From Where? (1)

Confusedent (1913038) | more than 2 years ago | (#39536287)

Overreaction much? Blame the journalists not the researchers, I don't think they're doubling as full-time PR people.

Re:From Where? (0)

Anonymous Coward | more than 2 years ago | (#39536309)

They probably had to approve the press release.

Re:From Where? (0)

Anonymous Coward | more than 2 years ago | (#39537555)

It's on their own website. Not the newspaper, not some reporter, it's their own freaking site that they're spewing this on.

No wonder no-one believes scientists anymore - people making claims like this are pyramid scheme-esque in their exaggerations.

Re:From Where? (2)

nojayuk (567177) | more than 2 years ago | (#39535901)

Sound like a smaller version of SMART-1 launched in 2004 which used an ion thruster consuming 80kg of xenon propellant to move a 300kg satellite from orbit around Earth to a Lunar orbit about 15 months later. The neat thing you're suggesting is doing it with a microsatellite although whether it could carry out any sort of useful function once it was in Lunar orbit is debatable; just having enough radio transmission capability to return scientific data to Earth on such a small satellite would be a major stumbling block.

Re:From Where? (0)

SuricouRaven (1897204) | more than 2 years ago | (#39536113)

Ultra-small and little propellant? I don't see a moon transport there. I see a sat manouvering/orbit-maintainance/deorbiting thruster. Even a very little thrust would be of a lot of use there, but weight matters.

Re:From Where? (1)

chebucto (992517) | more than 2 years ago | (#39536241)

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] :)

Re:From Where? (0)

Anonymous Coward | more than 2 years ago | (#39537691)

For an Ion drive, I'd have expected a significantly higher speed for the ions, some significant fraction of c, i.e. at least 100000km/s instead of the 40km/s you achieve. Are there fundamental limits in the construction of your thruster, or are you going to increase the exhaust speed in a later version of the engine?

Re:From Where? (2)

wagnerrp (1305589) | more than 2 years ago | (#39538839)

Despite the futility of responding directly to an AC, there are inherent limits to an electrostatic (ION) drive. You increase your exhaust velocity by increasing your voltage, however if you increase your voltage too far, you arc between your electrodes and waste all your power. The only way to increase velocity is to build larger, increasing your gap, to allow for higher voltage. This actually achieves a higher exhaust velocity than it should by "cheating" in a pretty ingenious fashion. Rather than using one electrode to ionize the propellant, they're starting with an electrolyte, and using alternating current to prevent the build up of DC bias between the grid and the solution, effectively halving their operating voltage for the same performance.

Re:From Where? (0)

Anonymous Coward | more than 2 years ago | (#39535857)

"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."

But...but, this is /., a wretched and pathetic hive of stubborn geeky ignorance.
Proof: the guy above (hrshea) posts some actual, real information and gets modded 1!

Re:From Where? (-1)

Anonymous Coward | more than 2 years ago | (#39536783)

Timothy is known to be retarded, and should have been banned from slashdot long time ago... I no longer even bother reading anything here, since I know it is all garbage. I only even come here for the funny +5 comments...

Terrible site. Worthless.

Re:From Where? (0)

Anonymous Coward | more than 2 years ago | (#39542157)

Eh? I thought the links in the summary were to add a bit of colour to the text, I didn't know Slashdotters were allowed to click on them.

Re:From Where? (0)

Anonymous Coward | more than 2 years ago | (#39535849)

Just need to make sure you maneuver around the van alen belts correctly too...

Re:From Where? (1)

youn (1516637) | more than 2 years ago | (#39536571)

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 (4, Funny)

kamapuaa (555446) | more than 2 years ago | (#39535487)

Who would have guessed this got posted by Timothy!

Someone's reinvented the ion engine (3, Interesting)

Scareduck (177470) | more than 2 years ago | (#39535507)

Re:Someone's reinvented the ion engine (4, Interesting)

wisnoskij (1206448) | more than 2 years ago | (#39535589)

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.

Re:Someone's reinvented the ion engine (2)

EdZ (755139) | more than 2 years ago | (#39537169)

Except we did use it. To go to the moon. Over a decade ago [wikipedia.org] .

Re:Someone's reinvented the ion engine (1)

DerekLyons (302214) | more than 2 years ago | (#39538503)

But that here is a practical use of that engine that works better then anything else we are currently using.

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 (4, Informative)

mmmmbeer (107215) | more than 2 years ago | (#39535515)

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.

Re:Misleading (1)

halo_2_rocks (805685) | more than 2 years ago | (#39536111)

LOL Exactly!!! Why are people solving problems that we don't need solved and not solving things we really need solved? How about these geniuses come up with an economic way to get things from the surface of Earth into high earth orbit instead.

Re:Misleading (1)

wagnerrp (1305589) | more than 2 years ago | (#39538847)

We know how to do that, but all of the proposed systems either can't be used for complex (and organic) payloads, or leave large swaths of scorched Earth in their wake.

How is this new? (1)

JesusPGT (624264) | more than 2 years ago | (#39535531)

Ion thrusters have been around for a long time; NASA and the ESA have been using them for over a decade.

Re:How is this new? (3, Interesting)

queazocotal (915608) | more than 2 years ago | (#39535671)

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.

Re:How is this new? (1)

jamstar7 (694492) | more than 2 years ago | (#39535747)

Sounds like a great application for orbital solar power satellites beaming microwave energy to a rectenna onboard the craft. That is, if the engines can scale up.

Re:How is this new? (1)

K. S. Kyosuke (729550) | more than 2 years ago | (#39535843)

And even better, the smaller the satellite, the larger the surface (= power received) to mass (= inertia) ratio. Smaller satellites should get better acceleration from both solar cells and any kind of energy receiving equipment (microwave rectenna or solar cells illuminated by a CW laser, although microwaves are probably much more practical).

Re:How is this new? (2)

queazocotal (915608) | more than 2 years ago | (#39535871)

Well - yes, and no.

The fundamental problem with microwaves is - they're microwaves.
They are just another sort of radio, and like all radio waves, and light, and ... - they undergo diffraction.

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 - 40km.

So, you need an antenna 4km in diameter on your craft simply to pick up one percent of the beam at the moon.

Range is a major problem.

Lasers work somewhat better - but have their own annoying issues.

Re:How is this new? (1)

K. S. Kyosuke (729550) | more than 2 years ago | (#39536023)

Any reason why you wouldn't use, say, millimeter waves? 10 cm sounds like an awfully lot.

Re:How is this new? (1)

SuricouRaven (1897204) | more than 2 years ago | (#39536123)

Millimeter waves are very hard to produce, espicially at high power. Microwaves are easy, infrared is easy, but that gap in between is just hard to work with.

Re:How is this new? (1)

mk1004 (2488060) | more than 2 years ago | (#39536677)

Maybe something like this could be added to new comm satellites. Use an ion engine from LEO to GSO with enough fuel to bring it to re-entry at end of life. Or, maybe put back into LEO to refit and use again. As far as the Van Allen belt is concerned, shielding of sensitive components would be required.

Re:How is this new? (1)

ThreeKelvin (2024342) | more than 2 years ago | (#39537817)

While I do like that you're using SI-units, I find myself being a bit pedantic about your choice of units. Thrust is force, and therefore measured in Newton [N], not kg.

Re:How is this new? (5, Informative)

hrshea (2599465) | more than 2 years ago | (#39535839)

This ion thruster is unique by its extremely small size. we have miniaturized not only the ion emitter, but the entire thruster including high-voltage electronics and tank. Our complete thruster has a mass of 200g (including 100 ml of fuel), thus allowing it to be used on nanosatellites. It is the first high efficiency electric propulsion system that can be used in cubesats and 5kg satellites, such as those being planned for OLFAR The principle of operation of colloid thruster a bit different from the ion engines used fro instance on SMART-1, which uses ionize Xenon. in our case, we use a particular conductive liquid, an ionic liquid, from which we can extract both positive and negative ions. using a liquid avoids a pressurized tank, and allows for important simplification of the system (no valves, no heavy tanks, all flow controlled by capillary and electrostatic forces. using the ionic liquid allows the same speed as using a gas, but offers one big advantage: since we emit (from 2 chips in parallel) both positive and negative ions, the spacecraft stays electrically neutral, which is essential for electric propulsion to avoid having the ions fly back to the spacecraft. for more conventional electric propulsion systems, only positive ions can be emitted, so a neutralizer is needed to emit electrons to keep the spacecraft charge neutral. not having a neutralizer allows significant mass and power savings.
I'm biased, 'cause I work on this!
http://lmts.epfl.ch/microthust [lmts.epfl.ch]
- Herb Shea

Re:How is this new? (1)

K. S. Kyosuke (729550) | more than 2 years ago | (#39536057)

What kind of liquid compound do you use for the working mass? Also, the link does not work for me. You're probably missing an 'r' there.

Parent link is bad. Try this - (4, Informative)

Frosty Piss (770223) | more than 2 years ago | (#39536449)

Parent link is bad. Try this:

http://lmts.epfl.ch/microthrust [lmts.epfl.ch]

Re:How is this new? (1)

fritsd (924429) | more than 2 years ago | (#39536589)

I looked at the picture "Basic architecture of the electrostatic colloid thruster system" on the website (http://microthrust.live.valentnet.nl/technology/93-28.aspx [valentnet.nl] ).

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 second acceleration electrode?

Cool technology, thank you for participating here on Slashdot.

Re:How is this new? (0)

Anonymous Coward | more than 2 years ago | (#39537383)

The theory of operation described is neither new or novel. Such as the text book copyright 1968 sitting on my book shelf. Granted some of the manufacturing technology to miniturize is newer but still been around for at least a decade. Also if memory serves you can just alternate the polarization of the engine at appropriate frequency to avoid the charge problem if you are really going after miniture.

Seems there are lots of university students that need to learn how to do lit reviews.

Please clarify "fuel" vs. "propellant" (1)

Anonymous Coward | more than 2 years ago | (#39538025)

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 (1)

Doc Ruby (173196) | more than 2 years ago | (#39535543)

The fortune at the bottom of the page in which I'm posting says:

The most important service rendered by the press is that of educating people to approach printed matter with distrust.

But evidently Timothy doesn't read to the bottom of the page, either.

Impulse Engines (-1)

Anonymous Coward | more than 2 years ago | (#39535567)

Impulse engines! :) But seriously, its waaaay cheaper and resource-efficient to use Astral Travel (your mind/spirit travels as pure energy, without any phyical componenet, allowing faster-than-light travel since there IS NO MASS), at least until we invent a spaceship that's worth a damn.

Re:Impulse Engines (1)

maxwell demon (590494) | more than 2 years ago | (#39536187)

Sorry, but no mass means just traveling at light speed. Faster-than-light needs imaginary mass.

The expensive part (4, Interesting)

gmuslera (3436) | more than 2 years ago | (#39535601)

is launching to space from earth/moon surface. Traveling once there, and landing (at least in earth) could be relatively inexpensive. But once the space elevator, space fountain or other approaches are built and gives us relatively cheap ways to reach space, this kind of approachs could make a difference.

Re:The expensive part (1)

halo_2_rocks (805685) | more than 2 years ago | (#39536069)

Hehe. Once the space elevator is built?!? And just who is going to build it and how? It isn't going to happen in our lifetimes (or on this planet) given the current political and economic environment. Just think what would happen if some blew up one of those in construction!!! Wow.

Re:The expensive part (0)

Anonymous Coward | more than 2 years ago | (#39537065)

Just think what would happen if some blew up one of those in construction!!!

It's cool, Gundams would spontaneously appear and prevent the debris from falling on populated areas.

Re:The expensive part (0)

Anonymous Coward | more than 2 years ago | (#39539739)

Just think what would happen if some blew up one of those in construction!!!

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. :)

Re:The expensive part (1)

halo_2_rocks (805685) | more than 2 years ago | (#39540531)

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.

Re:The expensive part (0)

Anonymous Coward | more than 2 years ago | (#39541589)

Really, you are all missing the poiint of "how to do the job". Imagine this, equip the space ship with a team of teen age boys, confine them so that their erect penises are pointed in the direction of a one-way osmotic device allowing passage of Precious Bodily Fluids outwards with no truncation of velocity. Project appropriate pornographic images on their eyes via an inter-cranial link; since teenage boys manufacture seminal fluid at a rate of 250 to 500 mL per hour, their ejaculations would move the space vehicle at an astounding speed. Call it the Superman's semen effect, wherein when Superman ejaculates inside of Lana Long or Lois Lane or the creepy boy cub reporter, the sperm themselves share Super's super-powers and accellerate at monumental speed, faster than a speeding bullet, etc. In the case of this space ship, the ejaculating fluids will provide motive force, unlike the ejaculated super-seed which wold take off the tops of Lois/Lana?Cub-Reporter heads after eviscerating their insides. Problem solved and remember "In Space, there is no one to hear you moan", and even better, no "Clean Up on Aise Three!.

Fly me to the moon (1)

danielpauldavis (1142767) | more than 2 years ago | (#39535627)

Be sure to bring enough food to last the appreciably longer trip.

Microsats (1)

tsotha (720379) | more than 2 years ago | (#39535715)

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 size. Granted, you can launch oodles of them at once, but for that to be a good idea you need to have thought up a bunch of worthwhile experiments. If you have to pad it out with high school ant farms you may as well have built a bigger and more capable probe.

Ion engines are already pretty efficient... (3, Informative)

Metricmouse (2532810) | more than 2 years ago | (#39535861)

and that is not the big issue, as getting off the ground is always the big expense, but we all know that. This tech can be useful in reducing weight costs for sub orbital payloads though, and probably resembles the design of a DS4G engine. The problem with efficiency in the past is that motors required high voltages to accelerate the ions that collided with the electric field grids. DS4G used a two stage four line grid with the top grid closely spaced and of higher voltage, with an open spaced lower voltage bottom grid. These differences between these stages allow higher velocity without ion grid collision at overall lower voltages resulting in 4x the fuel efficiency of previous engines.

My god, it's full of dumb! (1)

Anonymous Coward | more than 2 years ago | (#39536053)

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!

Re:My god, it's full of dumb! (1)

jamesh (87723) | more than 2 years ago | (#39537123)

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... (1)

Dr. Spork (142693) | more than 2 years ago | (#39536143)

So if these things are so damn efficient but also weak, would it make sense to move big structures with a whole giant slew of these thrusters? Or do they individually scale up? How much fuel would it take to move something of the mass of the ISS into Martian orbit? That would be traveling in style!

Getting into orbit (1)

nurb432 (527695) | more than 2 years ago | (#39536399)

Is biggest expense of fuel i bet.

gundam (0)

Anonymous Coward | more than 2 years ago | (#39536423)

...the war draws nearer...

Provenance (0)

Anonymous Coward | more than 2 years ago | (#39536607)

There are many good reasons I use Kitten Block [tomroyal.com] , and this article is an example of one of them. A Daily Mail article about science goes like this:

EXTRAVAGANT, SENSATIONALIST CLAIM WHICH HIGHLIGHTS OUR IGNORANCE

Some boffins somewhere did something frightfully clever, which we didn't understand in the slightest. As we can safely assume that, as a Daily Mail reader, you are completely uneducated, we're pretty safe assuming you wouldn't understand it either. A rocket was mentioned, though, and all we could think about was the Jetsons, so that's what's going to happen. And it will cure cancer.

And when rocket fuel is just $2.00/gallon (1)

l0ungeb0y (442022) | more than 2 years ago | (#39536831)

We can build our Moon Base for super-cheap with exported Mexican labor!
NEWT!!! NEWT!!! NEWT!!! NEWT!!! NEWT!!! NEWT!!!

Ah, it's been a while (0)

Anonymous Coward | more than 2 years ago | (#39536875)

since the last hopelessly naive, wildly over-optimistic, foaming-at-the-mouth delirious Space Nutter story. Pathetic.

Unrealistic (1)

Shavano (2541114) | more than 2 years ago | (#39537075)

How big would this thing need to be to get a human being to the moon in under a week?

April 1 (1)

jamesh (87723) | more than 2 years ago | (#39537101)

According to slashdot this article was posted April 1... I'm not buying it.

things in space have always been relatively cheap (1)

crutchy (1949900) | more than 2 years ago | (#39538385)

its getting there that’s not

oh great... (1)

slashmydots (2189826) | more than 2 years ago | (#39538873)

Great, now when I start to feel like perhaps my GPS device is taking me to the moon on the way to downtown, it actually might be. Though, how settling it is to know that next time I'm golfing on the moon, they could have an array of GPS satellites in orbit that will tell me where the next hole is. It really all starts to look the same up there after a while.
But seriously, what is there to do with satellites around the moon? Certainly something less useful than around Earth. Still neat though.

i was first (0)

Anonymous Coward | more than 2 years ago | (#39544205)

I have a similar engine, utilizing digestive products of leguminous vegetables.

Ionic chemical compound... (1)

BillX (307153) | more than 2 years ago | (#39545449)

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 station-keeping) on small satellites... although there are probably other sizes for other applications.

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