Beta
×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

First Exotic Space Thruster Test Ends in Explosion

ScuttleMonkey posted more than 6 years ago | from the not-the-fireworks-they-were-hoping-for dept.

Space 178

KentuckyFC writes "A NASA-funded test of an entirely new way to control orbiting satellites has ended with the prototype arcing dangerously and parts of the machine exploding. The new propulsion system is based on the Lorentz force: that a charged particle moving through a magnetic field experiences a force perpendicular to both its velocity and the field. So the plan is to ensure that a satellite passing though the Earth's magnetic field is electrically charged so as to generate a force that can be used to steer the spacecraft. The advantage of the idea is that it requires no propellant, which is a big deal since most satellites' lifespans are limited by the amount of fuel they can carry. But the first ground-based tests haven't gone entirely to plan."

cancel ×

178 comments

Sorry! There are no comments related to the filter you selected.

I hope (5, Funny)

VeNoM0619 (1058216) | more than 6 years ago | (#23522400)

parts of the machine exploding.

But the first ground-based tests haven't gone entirely to plan."
Good thing they told us that... I was beginning to lose faith in their work.

Explosions are an indicator of work (5, Insightful)

iamlucky13 (795185) | more than 6 years ago | (#23523716)

The best projects usually have a development report buried somewhere in their history that contains the phrase, "...and then it exploded."

Percy Spencer (microwave oven): "...and then the egg exploded."
James Watt (steam engine): "...and then the boiler exploded."
Alfred Nobel (dynamite): "...and then the nitroglycerin-soaked soil exploded."
Vladmir Titov (Russian cosmonaut): "...and then the Soyuz rocket exploded."
Werner von Braun (NASA engineer): "...and then the Jupiter rocket exploded."
Yang Liwei (Chinese Taikonaut): "...and then the Long March rocket exploded."
Sony test engineer: "...and then the battery exploded."
J. Robert Openheimer: "...and then the Trinity device exploded"...oh wait, that was supposed to happen.

A more personal anecdote:
Someone in the shop at work needed a simple room-temperature dryer for a special project, so he got some large diameter PVC pipe that was handy, filled it with a desiccant, put the material in that needed drying, and screwed the cap on. Then he left it alone for a few hours.

Apparently some sort of gas-producing chemical reaction took place, probably helped by the sun shining through the open door, (...wait for it...) and then the drying chamber exploded, blasting the plastic lid through the ceiling 25 feet overhead and covering the work bay with the tiny pellets of desiccant.

Engineering is fun.

Re:Explosions are an indicator of work (3, Funny)

jberryman (1175517) | more than 6 years ago | (#23524094)

Maybe "someone" (*COUGHyou) shouldn't be drying their special 'shrooms at work, eh?

Re:Explosions are an indicator of work (1)

rathaven (1253420) | more than 6 years ago | (#23524148)

Seconded! The bigger the bang the better... It means greater propulsion when it does get put right.

Funny? (4, Insightful)

dreamchaser (49529) | more than 6 years ago | (#23524186)

Yes there is humor here, but this should be +5 Insightful. Almost EVERY engineering endeavor has involved catastrophic failures at one point or another. If people stopped trying after one such failure we'd be using flint hand axes and making fire with a bow drill still, if even that.

Re:Funny? (2, Funny)

iamlucky13 (795185) | more than 6 years ago | (#23524220)

Point taken and considered while I was typing it, but just between you and me, I was going for entertainment value.

Heh (5, Funny)

Paranatural (661514) | more than 6 years ago | (#23522424)

From TFA: And as long as nobody gets hurt, a decent explosion livens up any experiment.

I'm pretty certain this is how Mythbusters got started.

Also from TFA: Obviously, a proplusion system that explodes while it is in operation needs some more work.

I dunno, kinda sounds like how rockets work.

Re:Heh (5, Funny)

Arimus (198136) | more than 6 years ago | (#23522642)

And not to mention the ill fated plan to detonate nuclear bombs behind a space craft as a method of propulsion...

(Orion programme if my memory isn't failing)

(On that point when will which ever god or other deity is responsible for our design fix the bloody faulty memory unit and start using error correcting cells?)

Re:Heh (5, Insightful)

geekoid (135745) | more than 6 years ago | (#23522842)

It's a valid method...just not inside the atmosphere.

Re:Heh (1)

Arimus (198136) | more than 6 years ago | (#23522876)

I dunno know - would cure the over population problem.

Might even stop global warming if it pushed the earth a bit farther out ;)

Re:Heh (1, Informative)

Anonymous Coward | more than 6 years ago | (#23523578)

It's a valid method...just not inside the atmosphere.
Maybe the same can be said for prototype in TFA. arcing should be less common in space.

Re:Heh (3, Interesting)

vux984 (928602) | more than 6 years ago | (#23523304)

(On that point when will which ever god or other deity is responsible for our design fix the bloody faulty memory unit and start using error correcting cells?)

Perhaps its a survival mechanism that keeps you from going insane and killing yourself before you reach age 10. The ability to forget might be the only thing keeping us sane.

Or maybe its a performance optimization - keeping the dataset smaller makes retrieval faster.

Or part of a disaster recovery system, enabling you not to be permanently traumatised after seeing the goatse guy. ;)

Re:Heh (1)

kesuki (321456) | more than 6 years ago | (#23523622)

Eidetic memory aside, there are countless things i can remember that i truly wish i could forget, and yet there are countless things i forget that i was trying really hard not to forget.

I mean, do i forever have to remember the time i nearly tripped and fell down a stairway and got a stick shoved through the roof of my mouth that i was holding in my mouth (was a toy magic wand) as i went downstairs to play with the magic wand? Why do i recall the time i was playing with my sister, hit the back of my head against a staircase, then remember as they brought me the pillow i thought it felt really warm for a pillow (because of all my blood, before i blacked out and from there remember only a brief flash of white light probably from when i was in the hospital after that)

and for as permanent those childhood memories are (I'm 30 now BTW) i have to make a complete written list of everything i need to buy at the store or i forget it all...

http://en.wikipedia.org/wiki/Eidetic_memory [wikipedia.org]

(On that point when will which ever god or other deity is responsible for our design fix the bloody faulty memory unit and start using error correcting cells?)

Perhaps its a survival mechanism that keeps you from going insane and killing yourself before you reach age 10. The ability to forget might be the only thing keeping us sane.

Or maybe its a performance optimization - keeping the dataset smaller makes retrieval faster.

Or part of a disaster recovery system, enabling you not to be permanently traumatised after seeing the goatse guy. ;)

Re:Heh (0)

Anonymous Coward | more than 6 years ago | (#23523836)

I mean, do i forever have to remember the time i nearly tripped and fell down a stairway and got a stick shoved through the roof of my mouth that i was holding in my mouth (was a toy magic wand) as i went downstairs to play with the magic wand? Why do i recall the time i was playing with my sister, hit the back of my head against a staircase, then remember as they brought me the pillow i thought it felt really warm for a pillow (because of all my blood, before i blacked out and from there remember only a brief flash of white light probably from when i was in the hospital after that)
It was probably punishment for "playing" with your "magic wand" too much.

Re:Heh (1)

kesuki (321456) | more than 6 years ago | (#23523562)

yes it was the Orion program, and as a matter of fact, it's the last best hope we in humanity have against a meteor or comet big enough to shatter a tectonic plate with it's impact (or to kick enough dust up to kill any animal not wearing air filters/ block out the sun for years or however long it takes for the dust to settle)

although, by the end of the Orion program, the idea was to build it in space (like a space station) and only detonate the bombs to get us all the way out to the large comet or asteroid (Orion was aiming for 21 humans on mars). to save the earth we'd have to get to it before it was too close, luckily we'd have 50 years to reach it, and destroy it or send it into Jupiter.

Re:Heh (1)

smaddox (928261) | more than 6 years ago | (#23523938)

I can just imagine sending an asteroid into Jupiter only for it to come out the other side and smack right into us.

It is a gas giant after all.

Re:Heh (1)

pyrrhonist (701154) | more than 6 years ago | (#23524172)

Is a comet [wikipedia.org] okay?

Re:Heh (1)

witherstaff (713820) | more than 6 years ago | (#23523982)

Orion [wikipedia.org] was canned because of treaties against upper atmosphere testing. I first saw the idea in the novel Football [wikipedia.org] . It sounds like it could actually work, but doesn't sound environmentally, or human, friendly.

It's Rocket Science (4, Funny)

mangu (126918) | more than 6 years ago | (#23522692)

Also from TFA: Obviously, a proplusion system that explodes while it is in operation needs some more work.

I dunno, kinda sounds like how rockets work.

Sure, you got the basic points all right. Now, let's see some advanced stuff:


It should go like this [youtube.com]


NOT like this [youtube.com] .

Re:It's Rocket Science (5, Funny)

TheRaven64 (641858) | more than 6 years ago | (#23522988)

You certainly get bonus points for irony using an Ariane 5 as an example of a rocket not blowing up...

Re:It's Rocket Science (5, Informative)

CCFreak2K (930973) | more than 6 years ago | (#23523618)

From Wikipedia [wikipedia.org] :

As with many rockets, the initial flights of each new Ariane model have seen failures. However, overall, the Ariane 4 and 5 are the most reliable commercial rockets ever launched. As of January 2006, 169 Ariane flights have boosted 290 satellites, successfully placing 271 of them on orbit (223 main passengers and 48 auxiliary passengers) for a total mass of 575 000 kg successfully delivered on orbit. This success rate also makes Arianespace the foremost commercial launcher; in some years, more than two thirds of all commercial satellites have been launched with the company's vehicles.

A better example (1)

xmark (177899) | more than 6 years ago | (#23523954)

would be this. [youtube.com] That's Spirit on its way to Mars aboard a Delta 2. Same rocket that was used to send Phoenix to Mars. Works for me.

Re:Heh... for a few split secs, my eye saw (0, Redundant)

davidsyes (765062) | more than 6 years ago | (#23522856)

"Erotic Space Thruster..."

That WOULD be an electrically stimulating charge with re-entry on that massive a scale...

Re:Heh (0)

Anonymous Coward | more than 6 years ago | (#23522882)

how long before someone posts the "mythbusted" pic which can best be described as Jamie doing his own impression of Goatse

Lichtenberg said it.. experiments w/bang are best (0)

Anonymous Coward | more than 6 years ago | (#23523728)

Georg Lichtenberg in the 18th century:
A physical experiment which makes a bang is always worth more than a quiet one. Therefore a man cannot strongly enough ask of Heaven: if it wants to let him discover something, may it be something that makes a bang. It will resound into eternity.

Good for them (5, Insightful)

LGV (68807) | more than 6 years ago | (#23522464)

I'm actually glad to see NASA doing stuff that might not work. It seems that a lot of the space work thats been happening in the last decade or two has been stuff that we know we can do. There are still failures, but those tend to be metric vs imperial units issues, not because they're pushing forward in to new areas.

All new technology generates it's share of failures along the way. In the early days NASA blew up a lot of rockets in the process of learning to get them in to space. As long as we're using it on unmanned craft (or on the bench), a decent rate of failures is alright by me if they're learning something from them.

Re:Good for them (4, Insightful)

jedidiah (1196) | more than 6 years ago | (#23522632)

Goddard started out the same way...

Re:Good for them (4, Funny)

Applekid (993327) | more than 6 years ago | (#23522740)

As long as we're using it on unmanned craft (or on the bench), a decent rate of failures is alright by me if they're learning something from them.
I'd have to say that mindset is the #1 reason why I like science so much. Even in failure there's so much to learn from it.

So I'm glad I got burned think of all the things we learned
For the people who are still alive

Re:Good for them (0, Offtopic)

Rycross (836649) | more than 6 years ago | (#23522798)

So would you say that its hard to overstate your satisfaction?

Re:Good for them (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#23523012)

Well, we do what we must because we can.

Re:Good for them (3, Informative)

DerekLyons (302214) | more than 6 years ago | (#23523834)

I'm actually glad to see NASA doing stuff that might not work. It seems that a lot of the space work thats been happening in the last decade or two has been stuff that we know we can do.

NASA has never stopped doing stuff that might not work - it's just that 99.99% percent of what does (successful or not) never makes Slashdot, let alone the mainstream media. Heck, even most of the stuff that's made the mainstream media hasn't really been 'stuff we know how to do'... Pathfinder, Spirit, Opportunity. Deep Space 1, Deep Impact, the Hubble repair missions, quite of the ISS assembly flights... I could go on, but those alone should suffice.
 
 

There are still failures, but those tend to be metric vs imperial units issues, not because they're pushing forward in to new areas.

Had NASA suffered a failure because of a units error - you'd have a point. I assume you mean Mars Climate Orbiter - which was lost because NASA failed to analyze it's trajectory during the cruise phase. Not because of a units error. The units error was a contributing cause, but one trivially corrected for had standard monitoring been in place (both in testing and in flight) - but it wasn't because of sharp budget restrictions.
 
Not to be offensive, but it seems your impression of what NASA is or isn't doing seems to arise from not paying attention.

Re:Good for them (1)

linzeal (197905) | more than 6 years ago | (#23524082)

Just because you read slashdot does not mean you are not the most scientifically literate person on the planet. I love people that pretend that it is. Science is hard work and should not be trivialized.

Re:Good for them (0, Flamebait)

DerekLyons (302214) | more than 6 years ago | (#23524128)

Just because you read slashdot does not mean you are not the most scientifically literate person on the planet.

One doesn't have to be the most scientifically literate person on the planet to keep up with what NASA is doing. Not even close.
 
 

I love people that pretend that it is.

I did not 'pretend' anything, I simply stated bald facts. Ignorant jackasses like yourself may have a hard time telling the difference since they wallow in their ignorance and wear it as if was a badge of honor.
 
 

Science is hard work and should not be trivialized.

Ah, the final sign of a total ignoramus - throw in a statement that, while true, has absolutely nothing to do with the discussion. It makes the ignorant feel like they are smart, since they can parrot things they've read elsewhere, but to anyone with an education it merely reveals the shallowness of the jackass they are conversing with.

Re:Good for them (1)

linzeal (197905) | more than 6 years ago | (#23524226)

I was agreeing with you. Sorry, if it seemed an attack.

Dirty (5, Funny)

Hatta (162192) | more than 6 years ago | (#23522466)

I'd be concerned if I tested my exotic thruster and it didn't end in an explosion.

Re:Dirty (1, Funny)

Kryptonian Jor-El (970056) | more than 6 years ago | (#23522504)

That's what she said

Re:Dirty (4, Funny)

p0tat03 (985078) | more than 6 years ago | (#23522682)

"She" has an exotic thruster? o_O

Protection (2, Funny)

DeadDecoy (877617) | more than 6 years ago | (#23522922)

Ya, but you might want to use protection or you'll get burned.

Re:Dirty (2, Funny)

Anonymous Coward | more than 6 years ago | (#23523550)

Well, that's why she's so exotic.

Re:Dirty (0)

Cajun Hell (725246) | more than 6 years ago | (#23522704)

Woooooo!

Doesn't seem like a significant setback. (5, Interesting)

Pendersempai (625351) | more than 6 years ago | (#23522470)

Here is the story, based on my admittedly non-expert reading: To use the (very exciting) Lorentz steering technology, the sattelite has to have an electric charge. The method they used to obtain the charge is to apply a voltage to a radioactive substance and then allow solar wind to carry away the positive charge, leaving the sattelite negatively charged. The problem seemed to be that this process caused sparks to arc across the sattelite, which in turn damaged electronics and dislodged soldering.

I'm not sure why this is a big deal. Couldn't they just use a different kind of solder, or at least insulate vulnerable electronics from the charge?

Re:Doesn't seem like a significant setback. (4, Interesting)

v1 (525388) | more than 6 years ago | (#23523810)

That's what I was working on figuring out, from the wording of the article ("explosion") it made it sound like a big deal, like when a rocket launch goes bad. (see various youtube links in this thread)

But when I got to reading, they use the word "explosion" for solder. Solder is not big. It's not like a fuel tank went up - this is a little bit of electronics. That sounds like a smaller explosion than you get with your average match when you strike it.

That's like talking about buildings and saying there was a "collapse", and if you RTFA close enough you find what they're actually referring to is the water glass on the table in the lounge tipped over.

Honest perhaps, but definitely deceptive.

Re:Doesn't seem like a significant setback. (3, Interesting)

smaddox (928261) | more than 6 years ago | (#23524002)

It seems like arcing shouldn't be a huge problem in a vacuum. The charge would have to be isolated from electronics, because transistors wouldn't work very well if they had a high initial base charge.

However, isolating the transistors might be harder than it seems at face value because transistors must be used to control the mechanics of the satellite. If you tried to isolate the charge to the metallic chassis, it might be able to pass through control lines into the electronics. The resulting electric field could either keep transistors from depleting, or even worse, blow the dielectric.

It seems to me that an isolated piece of metal would have to be incorporated specifically to hold the charge. In order to isolate it you would need a dielectric with a very high breakdown voltage. However, even then the isolated charge would cause electric fields to appear across the rest of the satellite.

Hmm... That is not an easy problem at all.

Re:Doesn't seem like a significant setback. (1)

nahdude812 (88157) | more than 6 years ago | (#23524038)

<pedantry>I think since a positive charge is actually too few electrons, instead of solar wind carrying away the positive charge, it's depositing a negative charge (nothing is carried away).</pedantry>

It may be an issue that eventually enough charge is built up without any means of eliminating the excess that the voltage defeats conventional insulations.

dear mods (0)

Anonymous Coward | more than 6 years ago | (#23522488)

read the artical.... microscopic arcing resulting in solder "exploding" is not exactly a big deal.. sounds like they need to use a better joining compound then some shitty solder with lots of flux pockets

Need more coffee (4, Funny)

truthsearch (249536) | more than 6 years ago | (#23522492)

My brain initially processed the title as, "First Erotic Space Thruster Test Ends in Explosion". Needless to say I was very disappointed when I read the summary.

Re:Need more coffee (0)

Anonymous Coward | more than 6 years ago | (#23522688)

Stay away from my toaster.

best to discover flaws early (4, Insightful)

peter303 (12292) | more than 6 years ago | (#23522494)

You should watch videos of our first satellite attempts. I'm surprised we didnt have more fried astronauts.

EPIC LULZ (-1, Flamebait)

Anonymous Coward | more than 6 years ago | (#23522498)

us russians, and the chinese are wayyy ahead of you filthy americans in space research.

you can thank george bush for cutting your funding and nasa middle management for their bickering.

Re:EPIC LULZ (0)

Anonymous Coward | more than 6 years ago | (#23522664)

Are you SURE you aren't a product of the American Schooling system?

Re:EPIC LULZ (0)

Anonymous Coward | more than 6 years ago | (#23523120)

well he did call us filthy.

Re:EPIC LULZ (0)

joeman3429 (1288786) | more than 6 years ago | (#23523664)

I'm actually glad. The last time America got off it's ass what because we were trying to stay ahead of the russians. If it takes a cold war with china to get us to the next level, I support that :p

Jazzing up the story a bit (5, Informative)

Goaway (82658) | more than 6 years ago | (#23522512)

As much as we all like a good explosion, that summary seems highly misleading. From the abstract:

Microscopic arcing was observed at voltages as low as -300 V. This arcing caused solder to explode off of the object. Insulating the object allowed the charge to remain on the object longer, while in the plasma, and also eliminated the arcing. However, this insulation does not allow a net charge to reside on the surface of the spacecraft.
"Caused solder to explode off the object" hardly sounds like much of an explosion.

Re:Jazzing up the story a bit (5, Funny)

eln (21727) | more than 6 years ago | (#23522574)

Oh sure, it doesn't sound that impressive until you realize the entire craft was covered in a 2-foot layer of solder.

Re:Jazzing up the story a bit (4, Insightful)

ivan256 (17499) | more than 6 years ago | (#23522618)

When you play back the high-speed camera footage taken through a microscope on a 100" screen...

Oh, nevermind... Even then it's probably not a very impressive explosion.

It bothers me that the editors here simultaneously push the "we don't invest enough in space research" platform, and fall into the "journalistic" trap of sensationalizing NASA's failures to make their readers feel "smarter than those rocket scientist guys".

I have every expectation that the readers and comment writers on Slashdot have vastly differing opinions on the subject, but you'd think that the clearly biased editorial staff here could get their story straight.

Re:Jazzing up the story a bit (1)

maxume (22995) | more than 6 years ago | (#23522840)

I don't think it is really a good idea to treat the editors as a coherent group.

Re:Jazzing up the story a bit (2, Funny)

Slashdot Suxxors (1207082) | more than 6 years ago | (#23522920)

You must be new here.

Re:Jazzing up the story a bit (1)

ivan256 (17499) | more than 6 years ago | (#23522948)

Why shouldn't we? Is that too much to expect? It seems perfectly reasonable to me to assume that a "news" organization can have a uniform policy of reasonable standards that they could hold their editors to.

Re:Jazzing up the story a bit (2, Funny)

TheRaven64 (641858) | more than 6 years ago | (#23523024)

Hell, it's not even safe to treat the individual editors as coherent...

A real arc (1)

Skapare (16644) | more than 6 years ago | (#23523940)

You don't know what a real arc is until it hits your house [youtube.com] .

Redefining your way to success! (5, Funny)

Chris Burke (6130) | more than 6 years ago | (#23522520)

A NASA-funded test of an entirely new way to explode orbiting satellites has ended with promising success!

Well I certainly wouldn't (3, Insightful)

iminplaya (723125) | more than 6 years ago | (#23522528)

let a little thing like an explosion [nasa.gov] deter me.

Re:Well I certainly wouldn't (1)

maxume (22995) | more than 6 years ago | (#23522662)

You obviously don't drink microbrews.

Re:Well I certainly wouldn't (1)

iminplaya (723125) | more than 6 years ago | (#23522824)

Well, I used to drink Coors, when it was considered exotic.

Re:Well I certainly wouldn't (1)

maxume (22995) | more than 6 years ago | (#23522880)

Shouldn't you be dead?

Re:Well I certainly wouldn't (1)

iminplaya (723125) | more than 6 years ago | (#23522978)

I didn't say I liked it...

Re:Well I certainly wouldn't (2, Funny)

EricTheGreen (223110) | more than 6 years ago | (#23522998)

From old age or the beer?

Re:Well I certainly wouldn't (1, Funny)

Anonymous Coward | more than 6 years ago | (#23523612)

Maybe they meant from the delivery process. "Breaker, breaker, where are you Bandit? I got a smokey on my tail." Not being "legal" in many states added to its "exotic" flavor causing some excitement regarding the "Colorado Coolaid". Han and Luke, Bandit and Snowman, it can be good having a smugler covering your backside, but if you were either you were in danger. Of course if all you did was help drink it at the frat party or at the drivein, the danger lessens.

Re:Well I certainly wouldn't (0)

Anonymous Coward | more than 6 years ago | (#23523282)

ich keine [youtube.com] !

Okay, so the big news is... (-1, Troll)

mr_mischief (456295) | more than 6 years ago | (#23522608)

that a strongly charged gas cloud can wreak havoc on your sensitive electronics if you don't shield them properly. Oh, and putting insulation around your stuff cuts down on the charge that will move across it. That's your government's bondholder money at work!

Re:Okay, so the big news is... (2, Insightful)

geekoid (135745) | more than 6 years ago | (#23522684)

Wow, you had to stretch to come to your spurious conclusion about the myth that the government is full of incompetents and money wasters.

Another variant also had problems. (5, Informative)

Ungrounded Lightning (62228) | more than 6 years ago | (#23522638)

Another variant of this is to have two weights connected by a wire tether and tide-locked to the primary, so the wire is oriented at roughly right angles to the orbit. Then you put a current in the wire by ejecting electrons on one end and collecting them at the other - making it into a motor that can accelerate or decelerate along the orbit. No reaction mass, run it off the solar collectors, etc. This also ran into issues with arcing.

They tried an experiment on this with the shuttle and a tether to a satellite they were launching, and found a problem: The motion along the orbit also causes it to act like a generator, powered by the orbital momentum. (This was known - and also has possible uses.) This produces a voltage gradient along the wire tether. So the tether has to be insulated to prevent arcing to the very low-pressure plasma that constitutes the high atmosphere and solar wind.

What they discovered was that minute flaws in the insulation caused localized arcs to the surrounding plasma. These were powered by the orbital motion relative to the earth's field and were very intense. They quickly melted through the thin tether.

So such a motor is not an impossibility. But it will require some heavy engineering work to get around this problem.

(It also says that large-scale tethered orbital structures have an additional problem to be solved: Keeping the tethers intact despite kilovolts of induced voltage along the tether and the resulting arcing.)

It's easy to think of space as filled with a hard vacuum. Unfortunately it's actually filled with very low pressure conductive plasma and near the Earth that's dense enough to be a major engineering issue.

Re:Another variant also had problems. (3, Informative)

Jesus_666 (702802) | more than 6 years ago | (#23523186)

So the lesson is "moving something by ionizing part of it is pretty hard to do in a conductive medium". Another lesson people tend to forget is "space research is all about blowing up things until you get it right". A new propulsion technology not working as expected during the first few trials is not quite counterintuitive.

Re:Another variant also had problems. (1)

argent (18001) | more than 6 years ago | (#23523226)

The motion along the orbit also causes it to act like a generator, powered by the orbital momentum. (This was known - and also has possible uses.)

Don't forget the ObReference: Tank Farm Dynamo [davidbrin.com] .

Re:Another variant also had problems. (1, Insightful)

Anonymous Coward | more than 6 years ago | (#23523242)

"large-scale tethered orbital structures have an additional problem to be solved: Keeping the tethers intact despite kilovolts of induced voltage along the tether and the resulting arcing"

Would those same issues apply to a Space Elevator?

Re:Another variant also had problems. (2, Interesting)

Ungrounded Lightning (62228) | more than 6 years ago | (#23524100)

"large-scale tethered orbital structures have an additional problem to be solved: Keeping the tethers intact despite kilovolts of induced voltage along the tether and the resulting arcing"

Would those same issues apply to a Space Elevator?


To a much smaller extent - at least for the skyhook/beanstalk variety. (Some of the tumbing ones might have issues.)

A skyhook is rotating with the Earth, which also means with the Earth's field lines. Or at least roughly:
  - Any waving back-and-forth in the beanstalk will induce voltages. (Climbers will cause it to wiggle, as will several kinds of weather.)
  - So will distortion of the Earth's field by bow shock (which will cause its position to vary with respect to a tide-locked beanstalk, depending on the time of day.
  - So will sudden distortions of the Earth's field by solar flares and such. (You think you get a big voltage induced in a power transmission line crossing a continent? Imagine what you get in one several times the diameter of the planet...)
  - And beyond the bow shock you're dealing with the the galactic field, which DOESN'T rotate with the earth. (I think the bow shock is beyond the Clarke orbit but I'm not sure at all.)

And of course down here where the atmosphere is thicker than a neon sign's content you have all sorts of other electrical stuff - lightning, sprites/jets, voltages from the ionosphere, etc.

So skyhooks have the issue, mitigated by moving generally with the field and by the extreme thickness of the cable but exacerbated by it's length.

Upside: Charge collectors and electron guns at various heights along the tether can be used to induce currents in segments of the tether. This can be used to damp the component of any oscillations that's at right angles to the Earth's field. (That's the big ones.) (Also: Damping oscillations means throwing energy away. So the sense of the generated voltages should be helping, rather than hurting, the powering of the dampers.)

dependant on earth's magnetic field? (4, Interesting)

lobiusmoop (305328) | more than 6 years ago | (#23522672)

Will this screw up when the earths field begins fluctuating when poles being going into reversal again?

Mind you, when this begins, I suspect the last thing we would be worried about if/when this comes would be the odd satellite crashing back to earth.

Re:dependant on earth's magnetic field? (1)

Jeff DeMaagd (2015) | more than 6 years ago | (#23522874)

I don't think the satellite is going to last that long, I don't expect to see a pole reversal in the next decade, I think it's more like hundreds of years away.

Re:dependant on earth's magnetic field? (2, Informative)

dvase (1134189) | more than 6 years ago | (#23523174)

Will this screw up when the earths field begins fluctuating when poles being going into reversal again?
Seeing as the force generated is in a direction perpendicular to both the satellite's direction and the magnetic field lines, it really shouldn't have a major effect.

As long as the magnetic field stays at least somewhat parallel to the earth's surface, a lift force will be generated regardless of the field polarity.

Of course, if there is zero magnetic field that means no lift force, but that doesn't mean things immediately fall out of the sky, only the potential to drop a little in orbit until the field picks up again.

Good News, Everyone. (1)

Shinmizu (725298) | more than 6 years ago | (#23522788)

Now, we know what could possibly go wrong. Won't need the tag for this one.

Re:Good News, Everyone. (0)

Anonymous Coward | more than 6 years ago | (#23523868)

I laughed.

That tag stopped being funny quite a while a ago.

Not sure that was the best approach.... (3, Insightful)

CBob (722532) | more than 6 years ago | (#23522790)

(pun intended) I suspect possible solder join problems here. The voltages they're working with are not exactly known for freely arcing unless it's a short. I did notice no mention of the current involved tho. If it was a high current application, it points to someone not insulating correctly. Over-ionized maybe? The excerpt didn't fill too many details in.

Lame (-1, Troll)

Anonymous Coward | more than 6 years ago | (#23522794)

They could have at least strapped this thing to an X-wing...

We never landed on the moon

Refueling (2, Informative)

visible.frylock (965768) | more than 6 years ago | (#23522796)

I was surprised to learn that satellites are not refueled more often. After a bit of googling, this pdf [dtic.mil] came up. From page 15:

Although the use of shuttle manned EVA evolutions to conduct on-orbit servicing has proven sucessful in LEO, shuttle operational limits preclude operations above 400nm. Satellites which operate in MEO or GEO with typical altitudes of as high as 22,000 nm are not accessible to shuttle flights at this time.

This was from 1996, but as I understand, basic shuttle capabilities haven't changed much (someone correct me if I'm wrong). I think nm is nautical mile (1.852km).

Re:Refueling (0)

Anonymous Coward | more than 6 years ago | (#23523088)

I think nm is nautical mile
I thought it was nanometers

Re:Refueling (1)

Jesus_666 (702802) | more than 6 years ago | (#23523238)

I think nm is nautical mile (1.852km).
If it were nanometers it would mean that LEO and MEO satellites were a serious threat to kneecaps. Geostationary satellites would be much easier to implement, though.

Why bother? (0)

Anonymous Coward | more than 6 years ago | (#23522932)

Torque rods are already used for this very application- a torque rod is just a long pole with an electromagnet wound inside. They typically protrude in one or more axis that you want to move in, and you interact with the earth's magnetic field to control attitude.

Why the $#@* would you want to not use that well proven, reliable method and use this bizzare charge manipulation method?

I know it's Friday at quitting time... (0, Redundant)

catdevnull (531283) | more than 6 years ago | (#23523058)

I know it's Friday at quitting time because I read that summary title as "First Erotic Space Thruster Teste Ends in Explosion"

Damn. I'm still snickering like an 11 year old...

It's never too late to have a happy childhood. Too bad my inner child is Beavis.

Re:I know it's Friday at quitting time... (1)

Fulcrum of Evil (560260) | more than 6 years ago | (#23523254)

Too bad my inner child is Beavis.

Beavis is everyone's inner child.

Re:I know it's Friday at quitting time... (0)

Anonymous Coward | more than 6 years ago | (#23523594)

Too bad my inner child is Beavis.

Beavis is everyone's inner child.

Unless Butthead is.

Not to be negative... (1)

Kingrames (858416) | more than 6 years ago | (#23523138)

...but EVERY space thruster test should end in an explosion.

on principle.

Re:Not to be negative... (1)

mozkill (58658) | more than 6 years ago | (#23523816)

yeah, the engineers are probably just having some fun.

They blow things up all the time (1)

esampson (223745) | more than 6 years ago | (#23523184)

I mean those guys are no rocket scientists.

What? Oh.....

They should have expected it. (4, Insightful)

Ptraci (584179) | more than 6 years ago | (#23523194)

This is how sputtering in a vacuum chamber is done, for manufacturing chips and coating surfaces. The company I work for builds power supplies for these vacuum chambers, and they generally require some arc handling circuitry. Here's [advanced-energy.com] a white paper on arcing.


If you have a negatively charged target in a plasma the target will attract positive ions which will knock bits off of the target if they arrive with sufficient velocity, otherwise they'll stick and neutralize the charge. In a sputtering chamber we want those bits knocked off. If we're sputtering something non-metallic we need to use RF to keep it charged.

The only failed test... (4, Insightful)

Tracy Reed (3563) | more than 6 years ago | (#23523340)

...is the one you don't learn anything from.

GO NASA!

Re:The only failed test... (1)

joeman3429 (1288786) | more than 6 years ago | (#23523680)

*gets out the pom poms*

doh! misread (-1, Redundant)

Anonymous Coward | more than 6 years ago | (#23523614)

anyone else read this as: First Erotic Space Thruster Test Ends in Explosion??

Warp Core Breach (2, Funny)

CodeBuster (516420) | more than 6 years ago | (#23523696)

One would think that NASA engineers had watched enough Star Trek to realize that if one does not reverse the polarity of the intermix injectors into the flow matrix before the plasma coolant leaks after a power surge then the warp core will breach...amateurs.

Re:Warp Core Breach (1)

mozkill (58658) | more than 6 years ago | (#23523788)

lol. that is really funny. thats a very well placed anecdote.

First Exotic Space Thruster Test Ends in Explosio (2, Informative)

Goondra (855859) | more than 6 years ago | (#23524154)

Spacecraft charge has long been a problem with satellites. The OGO IV satellite (circa 1968) was frequently negative due to the fact that the electron temperature in the ionosphere is higher than the ion temperature. As such there is a net electron flow to the satellite until its charge repels the electrons for a balanced +/- flow. But this is not always the case since the solar panels on the craft have exposed electrical contacts. The charging panels can drive electrons away from the craft and give (every once in a while) a net positive charge to the craft. Plasmas are tricky beasts. Simulations of the space environment on earth are frequently wrong.
Load More Comments
Slashdot Login

Need an Account?

Forgot your password?

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>