Ion-Propulsion Craft Reaches The Moon 395
Rollie Hawk writes "It ain't warp speed, but it's exciting new technology at work! The European Space Agency put an ion-propelled rocket into lunar orbit today. While not much horsepower is generated, this method of propulsion could be ideal for travel in near-weightless space as it does not require any combustion to occur."
Warp ? (Score:2, Funny)
But to me, it's a good step forward
Re:Warp ? (Score:3, Funny)
Peak of eternal light (Score:5, Informative)
Re:Peak of eternal light (Score:5, Interesting)
Re:Peak of eternal light (Score:5, Informative)
Re:Peak of eternal light (Score:2)
International treaties? BWAHAHAHAHAHA!
Re:Peak of eternal light (Score:2, Insightful)
Re:Peak of eternal light (Score:2, Insightful)
Re:Peak of eternal light (Score:5, Funny)
Re:Peak of eternal light (Score:2, Insightful)
You poor thing.
Re:Peak of eternal light (Score:4, Interesting)
Well of course nobody thinks the US will remain the leading superpower forever. Nobody who gives it any thought at least. At one point damned near ever real "power" on the earth was located in Europe. Now there's not a single nation in Europe that equals the United States. Together they do the job quite nicely though.
That's just it. Despite what we've seen from the former USSR there is life after being a superpower. Most Americans aren't living under the impression that the ride's going to last forever and only the small percentage of real paranoids think it has to at any cost.
I can't wait for us to return to being one of the pack so to speak. Then maybe our leaders wouldn't feel like it's necessary to station troops all over the planet. A military that can protect the United States is fine by me. An economy in the upper half of the world is more than many could ask for. Damn I'd like to see us get out of the world police business and back to the "working on making America better" business.
Re:Peak of eternal light (Score:3, Interesting)
I think after USA falls apart, the world should get together and have a "no superpowers" rule. But then again, there were no superpowers at the 70 years ago, and things didn't turn out so well. Europe sort of punched itself out, somebody else took ov
Re:Peak of eternal light (Score:3, Interesting)
And just how long would they remain "sane" when living with the status as "superpower"? How long before they too turned paranoid, or pissed off somebody and really got something to worry about?
Has there been studies on how even being targeted with nuclear weapoins for prolonged periods affects human psychology, and in the extent, foreign politics?
There was said something about how power corrupts.... Perhaps every state should have plans for how _not
Re:Peak of eternal light (Score:3, Informative)
Re:Peak of eternal light (Score:3, Insightful)
I don't really care how it happens (The US gets weaker or the rest of the world becomes stronger) because in the end it's the same thing.
I simply believe that a US military presence in countries like South Korea, Japan, and of course Germany is no longer needed. Prior to WWII we didn't have soldiers stationed in those countries (though of course we had them in the Philipines as we owned them at that time) and now that things in those areas are more than stable I see no reason to continue it.
Sure Nor
Re:Peak of eternal light (Score:3, Interesting)
You seem to be laboring under the misconception that wars begin for rational reasons. Do you know who Germany's largest trade partner was prior to WWI? France--
Re:Peak of eternal light (Score:2)
Re:Peak of eternal light (Score:5, Insightful)
It's as simple as that: if you made new land habitable, it should be yours. Maybe I'm a little romantic here, but making some land habitable comes first, then it becomes your property, then you defend it against possible intruders.
As long as there is enough land left on the moon, there will be no conflicts, if the people involved have the slightest hint of moral obligatons left. What they may or may not have anymore, considering this will be 20 years from now at a minimum.
In general, humans all alone on a vast amount of land, totally devoid of people, in a situation of need and struggle, they tend to build friendly relationships instead of murdering each other for a piece of land. Supply and demand. If there's enough resources, land in this case, left, people don't value that land high enough to commit crimes against their moral standards. Example: Australia. Even outlaws built a society, because they couldn't survive otherwise.
Sooner or later, people will fight their wars in space, of course. But not as long as there's millions of square kilometres left for anyone to take.
Re:Peak of eternal light (Score:3, Interesting)
As long as there is enough land left on the moon, there will be no conflicts, if the people involved have the slightest hint of moral obligatons left.
The words you are looking for here are: Lockean proviso. According to Locke, it is permissible to privatize a resource that you improve, provided you leave as much of the same (unimproved) quality for others. For example, you can privatize an oasis in the desert, so long as it
Re:Peak of eternal light (Score:2)
Re:Peak of eternal light (Score:3, Funny)
Sorta. You're probably thinking about the Lunar Treaty [demon.co.uk]. While that treaty only prohibits the actions of states, I doubt that a private industry would be able to claim moon land with any authority. Still, Article 9 specifically grants the authority to build moon bases provided "that they do not impede the free access to all areas of the moon by personnel, vehicles and equipment of o
Haven't been there. Done that. (Score:3, Interesting)
It's actually the one thing I miss the most. Once you've experienced life without any darkness, you realize how much the night cripples your life, and it's a hard thing to lose.
better article (Score:5, Informative)
Re:better article (Score:4, Funny)
Re:better article (Score:3, Informative)
-kaplanfx
Is it regular speed? (Score:5, Interesting)
Re:Is it regular speed? (Score:5, Informative)
In fact, ion drives tend to be rather energy-inefficient. However, they get their energy from electricity, which is renewed either by solar or RTG energy. Since RTGs are extremely energy-dense compared to conventional fuels, and solar cells constantly take in more energy, the penalty for a large amount of electrical waste and much, much larger propulsion system (for a given amount of thrust) is dwarfed by the benefits in terms reduced propellant mass.
Re:Is it regular speed? (Score:5, Interesting)
The problem with getting to Mars is fundamentally the radiation. If you send astronauts to Mars on a 0.70-year orbit, without any shielding against penetrating radiation, their radiation dose ends up being on the same order of magnitude as the dose that kills you. This is Not Good :-) There is a variety of ways to get around this:
Fundamentally, I don't see the justification for sending humans to Mars in the forseeable future. The really exciting science task would be to find out of there is unicellular life on Mars (with a positive result probably qualifying as the most important scientific result of the last 200 years). This can be accomplished with an uncrewed sample return mission.
Want to send humans to Mars? Great! Please dream up either (a) a valid scientific reason, or (b) a valid commercial reason. I don't think either exists presently, and I don't think either will exist within the next 100 years.
Re:Is it regular speed? (Score:5, Interesting)
While I agree that there *currently* isn't a good reason to send people to Mars, I think that once we can demonstrate some cost-effective mix of ability to mine low-G bodies, grow realistic amounts of food outside of Earth, create bulk raw structural materials outside Earth, and to produce fuel outside Earth, there is ample reason to work on colonizing Mars. Not only would being able to do these reduce the costs of operation, but even high costs could be justified by the future-potential of using Mars as a triangle trade with Earth and the asteroid belt (one of the few things I agree with Zubrin on). So, I would argue in favor of working on the technology with the goal of eventually having it become a realistic course of action.
Re:Extinction events (Score:3, Informative)
Re:Is it regular speed? (Score:3, Interesting)
Acceleration is painfully slow, but again, that's not necessarily a requirement of an ion drive. It may prove to be a practical limitation, however; we'll have to
Re:Is it regular speed? (Score:2)
Re:Is it regular speed? (Score:2)
Re:Is it regular speed? (Score:3, Insightful)
Unless you want to carry a few solar masses worth of xenon, you cannot get to relativistic speeds with an ion engine. The exhaust velocity of DS1 was 30km/sec. Now, C is 300,000 km/se
Speed of light... (Score:2)
Suppose you had an exhaust velocity of 1 m/s. Even if you were going 1000 m/s, and you pushed half your mass out at 1 m/s backwards, you would end up going 1001 m/s, despite travelling at 1000X the speed of your exhaust velocity.
Now, it IS an issue of efficiency of your propulsion mass. Energy can theoretically be stored wit
Re:Is it regular speed? (Score:3)
ISP is specific impulse. Roughly, ISP in a general (Earth) context is velocity/~9.8. So, given a hydrogen-oxygen rocket with an ISP of 450, this means that its exhaust is leaving at 450*9.8=4410 meters per second, or roughly half of the velocity for a LEO orbit. Compare this to a good ion drive which may give you ~40,000 m/s exhaust (still far from the ~300,000,000 m/s speed of light, mind you).
Re:Is it regular speed? (Score:2)
(/sarcasm)
Re:Is it regular speed? (Score:5, Interesting)
No, especially if you're aiming for extrasolar planets. Ion engines are good for a small payload that can take its time getting to where it's going. Humans (even those in some kind of imagined stasis) need something with a higher thrust to get where they're going in a reasonable time (ie, before cosmic radiation carves up their DNA, or a micrometeor holes their lifesupport system).
Re:Is it regular speed? (Score:2, Informative)
I think it was the TOS Trek episode "Spock's Brain" where Scotty commented on an ion-driven ship, "they could teach us a thing or two!" Right.
Re:Is it regular speed? (Score:4, Interesting)
However, it would be quite useful to use this technology to bring cargo to the Moon for possible astronauts to use. For instance, it's possible to deploy an entire habitat--crew quarters, energy producer, perhaps even in-situ resource production ("mining" water-ice for oxygen and hydrogen to feul your return vehicle)--all before we launch humans on a high-energy tracjectory that will get them there in three days, thus avoiding high radiation exposure.
You could do similar things with Mars. Here's a reference done by the Revolutionary Aerospace Systems Concepts part of NASA:
OASIS [nasa.gov]
It will take a suite of technologies to get safely to other planets, and possibly another suite of technologies to get back.
Re:Is it regular speed? (Score:2)
LoB
Re:Is it regular speed? (Score:3, Interesting)
However, an interesting oddity is that the SMART mission averaged a significantly higher speed than Apollo did: It spiralled out from the Earth, and travelled around 80,000,000 km, according to the Nature article someone posted. Apollo went to the moon pretty much by the shortest route.
Doing the math, I find the SMART average speed was around 8500 km/H, while Apollo averaged around 5500 km/H.
The latest score just in... (Score:2, Funny)
BEAGLE-0
Re:The latest score just in... (Score:2, Funny)
I don't get it (Score:4, Insightful)
What were you trying to say here? That combustion rockets are not a good way to travel through space? Maybe they're not the best, but it's going to be some time before anyone seriously considers getting people to the moon with ion engines.
Re:I don't get it (Score:5, Interesting)
So?
So this is crucial on the long haul. With a reaction drive, when you run out of reaction mass, you're done. The craft becomes inert. The trick here is that the saturn V was out fuel within 15 minutes, wheras this craft is still accelerating a year later. Concievably, it could run for another year, or a dozen. (I don't know how much reaction mass it has) An ion drive craft might be made that could with enough reaction mass for an interstellar voyage, where a chemical rocket could not. (esp. considering the mass needed to decelerate at the ead!)
Re:I don't get it (Score:2)
Re:I don't get it (Score:2)
Re:I don't get it (Score:2)
So when do we get to see the US flag? (Score:5, Funny)
[conspiracy] On the other hand, if they can't find it... [/conspiracy]
Re:So when do we get to see the US flag? (Score:2)
Re:So when do we get to see the US flag? (Score:3, Informative)
It REALLY Ain't warp speed (Score:5, Interesting)
I'm interested in seeing some comparisons with project cost, energy consumption, etc.
Re:It REALLY Ain't warp speed (Score:5, Insightful)
Re:It REALLY Ain't warp speed (Score:4, Informative)
To maintain the acceleration, you need sunlight hitting the solar panels. When you get that far out, the sunlight's going to be very weak. By then you might have picked up plenty of speed (I haven't done the math) but at the halfway point you won't have the acceleration you had near the inner planets.
Who needs sun? (Score:3, Informative)
Re:It REALLY Ain't warp speed (Score:2)
How long will it take to reach Mars? (Score:4, Funny)
Re:How long will it take to reach Mars? (Score:4, Funny)
wrong link (Score:5, Informative)
Plasma technology is the space enabler (Score:5, Interesting)
Re:Plasma technology is the space enabler (Score:4, Informative)
'Fraid not. To do that requires an enormous, lightweight, electrical power source. No current powerplant, solar, nuclear, chemical or other can provide enough power to generate high thrust when used with VASIMR.
VASIMR is a wannabe fusion power drive. Trouble is, fusion doesn't work well enough right now to use it for this; and they are stuck with trying to powering it the old fashioned ways. It works, but not noticeably any better than ion drive- if you were to get VASIMR to work with a new power supply, you can pretty much just gang up any of the existing ion drive thrusters and get about the same thrust.
VASIMR has theoretical advantages of being able to vary the exhaust velocity to increase the thrust, but even on the lowest settings I've seen them talk about, ion drives usually give better thrust.
Re:Plasma technology is the space enabler (Score:2)
Boeing has some power... (Score:4, Informative)
Re:Boeing has some power... (Score:2)
This is not the first ion drive... (Score:5, Informative)
It'll be interesting to see, if the Pluto probe ever flies, whether that uses ion propulsion. An ion drive could really make a difference on such a long-haul flight.
Re:This is not the first ion drive... (Score:2)
Yes, it really could make a difference. Specifically, it'd make the difference between how many times you'll have to say "great" before you get to the "grand-father was alive when they launched that thing" part of the conversation your descendants will have when it gets there.
Cheap Technology! (Score:5, Funny)
Re:Cheap Technology! (Score:2)
Re:Cheap Technology! (Score:3, Informative)
Inspite of early promise it turned out that the thrust/drag of the ramjet against solar wind and interstellar gas turned out to be below unity. That's bad- you don't go anywhere.
This lead to a concept called M2P2, which is an 'inflatable' plasma. You turn it on and it expands out to a few tens of kilometers, the solar wind pushes on it, and a few months later you are leaving the solar system at high speed, dragged along by the plasma
TIE Fighers? (Score:5, Informative)
Re:TIE Fighers? (Score:5, Funny)
Re:TIE Fighers? (Score:5, Funny)
No, the TIE fighters had a large bank of 48 car batteries which were kept topped up by the solar cells. Each TIE fighter had to charged up from the mains at least once every 48 hours, otherwise the battery would run flat, and you'd be stuck in space. In that case, the only way to start the engines was to plug an R2D2 unit into the cigarette lighter socket.
Re:TIE Fighers? (Score:2)
Now, somebody needs to explain how the maximum number of R2 units with unique ID's in the WHOLE FRIGGIN' GALAXY could only have been 1296???
Re:TIE Fighers? (Score:3, Funny)
"Luke, you may get away today, but in 12,000 years my total thrust will eventually exceed yours, and you'll be MINE!" -- Darth "Quickie" Vader
Sharper Image (Score:3, Funny)
There's really no end to the crap Sharper Image can add ions to and double the price for. It only stood to reason they'd release spaceships with them too.
You'll find them in their catalogue next to the negative ion vacuum cleaners, negative ion air purifiers, negative ion hair driers, negative ion bikini zone razors, and negative ion pet hair brushes (the scary thing is I only made one of that entire list up).
Re:Sharper Image (Score:2)
Science writing at its best (Score:5, Informative)
Brilliant science journalism there. If the smart probe was splitting atoms it wouldn't need solar panels. Not to mention you don't need to split atoms to get ions.
That reminds me of the article that was written on some research I was involved with. We were pulsing cells with high potential electric fields. The field strength was measured in MegaVolts per meter due to a very small gap between the electrodes, the actual voltage was only a kilovolt or so (over a 300ohm load for 5-15 ns). The journalist / engineer-reject thought that megavolts sounded really big and took it upon herself to proclaim that our pulse generators could power a whole city. Moan, groan....
Re:Science writing at its best (Score:2)
-josh
Re:Science writing at its best (Score:2)
How is weightlessnes relevant? (Score:5, Interesting)
No matter where the probe is, it has got the same mass, and hence the same inertia. Low-thrust engines work good in space because of no friction and often no requirement on quick travel (if it is a non-manned spacecraft). On earth an ion engine would never work for several reasons, one beeing friction against air and ground, but none of them has to do with the weight of the vechile/probe?
Or have I misunderstood something?
Re:How is weightlessnes relevant? (Score:2)
Fg is the force of gravity
M is the larger mass
m is the smaller mass
r is the distance between the center of hte two objects.
An object at the surface of the earth with a mass of 1 kg is subject to a gravitational force of 9.8N. At the moon, the gravitational force exerted by the earth on the 1kg mass, using newton's law of universal gravitation is 0.0026N.
So indeed, gravity and weight have a pretty big part to play in this. On the surface of the
Re:How is weightlessnes relevant? (Score:3, Insightful)
JPL has an open house every year. A few years back, they were in the middle of a multi-year burn test and during the open house, you could see the engine's blue glow as it sat there chu
NASA announces it will outdo the ESA (Score:5, Funny)
A similar proposal to go orbital (Score:2)
What is interesting about this approach is the high ISP might make space fairly cheap. Personally, I find the fact that travel using this means is slow somewhat interesting. Humanity might benefit by having some "wide open spaces". Communications inside the solar system would be rapid in any event. Slow transportation might act to help discourage things like rash, interplanetary wars.
Technical project info (Score:4, Informative)
Ion propulsion for cars! (Score:4, Funny)
Imagine ion propulsion in our cars! Just gimme some months to reach those 55 mph...
Re:ideal? (Score:2, Informative)
Ion drives are great in some situations, because they give you a lot more thrust (over time, of course) per pound, then chemical drives. I believe they're about 5 times as efficient. Thus, if you're not in a hu
Re:ideal? (Score:2)
Re:ideal? (Score:2)
While getting to Mars may not be that practical with this tech, Jupiter's or Saturn's moons might be.
Re:ideal? (Score:2)
Re:ideal? (Score:3, Informative)
Re:ideal? (Score:2)
Re:ideal? (Score:2)
Constant acceleration => time for trip is proportional to square root of distance
The ion drive provides constant acceleration. As you rack up distance the ion drive becomes many orders of magnitude faster than constant velocity drives.
Re:ideal? (Score:3, Informative)
This was not about speed. It was about low costs and testing of durability. The US did the testing with Deep Space one. ESA has elected to do a moon mission.
The engine has ran quite a while and has proven that it is well made. I suspect that with the next generations of satillites (micro-sats), this will be the norm for propulsion.
Re:ideal? (Score:2)
Re:ideal? (Score:3, Informative)
Re:Master of Orion (Score:2)
Apparently the folks at Micro Prose noticed this as well and disabled the heavy version via the patch...
Re:Not the best source in the world. (Score:3, Informative)
Yep... if you're uncomfortable getting your news from Rev. Moon (a.k.a. God himself) there are plenty of non-cult-affiliated links [google.com] for this story.
Re:One small... (Score:3, Informative)