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First Exotic Space Thruster Test Ends in Explosion
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."
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But we can be treated equal.
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.
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.
I'd be concerned if I tested my exotic thruster and it didn't end in an explosion.
Give me Classic Slashdot or give me death!
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?
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
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.
Developers: We can use your help.
You should watch videos of our first satellite attempts. I'm surprised we didnt have more fried astronauts.
A NASA-funded test of an entirely new way to explode orbiting satellites has ended with promising success!
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let a little thing like an explosion deter me.
What?
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.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Are you SURE you aren't a product of the American Schooling system?
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.
"I bless every day that I continue to live, for every day is pure profit."
Wow, you had to stretch to come to your spurious conclusion about the myth that the government is full of incompetents and money wasters.
The Kruger Dunning explains most post on
Sure, you got the basic points all right. Now, let's see some advanced stuff:
It should go like this
NOT like this.
Now, we know what could possibly go wrong. Won't need the tag for this one.
(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.
I was surprised to learn that satellites are not refueled more often. After a bit of googling, this pdf came up. From page 15:
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).
Billy Brown rides on. Yolanda Green bypasses Gary White.
"Erotic Space Thruster..."
That WOULD be an electrically stimulating charge with re-entry on that massive a scale...
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
Ya, but you might want to use protection or you'll get burned.
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 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.
I might know what I'm talkin' about, but then again, this is Slashdot...
well he did call us filthy.
...but EVERY space thruster test should end in an explosion.
on principle.
If you can read this, I forgot to post anonymously.
I mean those guys are no rocket scientists.
What? Oh.....
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.
...is the one you don't learn anything from.
GO NASA!
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
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.
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.
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.
You don't know what a real arc is until it hits your house.
now we need to go OSS in diesel cars
would be this. 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.
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.
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.
Of course, then all you need to do is charge the hull positively instead of negatively. (But it might not be possible to swap that without reconfiguring some hardware, which tends to be a problem in orbit.)
Have you been touched by his noodly appendage?
If you want to deflect the plasma (and thereby use the resultant Lorenz force to thrust your spacecraft), you have to use microsecond pulses of surface charge, not continuous charge like you would get from a weak alpha-emitter. Continuous charge = intact plasma filament = charge lead right back to your surface. Break the filament and you still get the expansion of plasma, with the resultant force transferred to the spacecraft through the magnetic field.
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Yeah it's an obscure joke.
Sorry about the writing. Robot fingers, you know? Cliff Steele in DOOM PATROL #23
"Houston, we have a problem."
So my physics teacher taught me. Doesn't that mean that while this doohickey might allow you to tweak the orbit, you can't actually raise or lower the orbit's semimajor axis?
Doesn't sound very useful.
Yes, that's the right project name, and US President George Bush naively named another project that of late. As far as your memory is failing, I'd like to point out that your brain still contains the memories, but you've managed the fuse the pathways (short the wires) with too much caffeine or asbestos or whatever fluff they use to make Teletubbies.
My thruster tests usually end in explosions, too.
Yeah baby!
This is the method of propulsion used by: the Sun the rest of the stars in the Universe, and is the primary propulsive of the Galaxies (from the net combined propulsion of the stars contained therein).
This of course is not taking into account the remaining velocity of the Universe's bodies from the Big Bang, but that is a residual velocity, as opposed to the current applied forces on those bodies.
that had to read the title a few times because I took it entirely wrong and was snickering for a few minutes?
Jason Nesmith: Did I just hear that the animal turned inside out, and then it EXPLODED?
Half baked theory: I wonder though, shouldn't using the earth's magnetic field as an energy source be discouraged - wouldn't that ultimately slow down the molten core reducing the magnetic field?
My first exotic thruster ended in an explosion as well, but I hit puberty a little early and didn't know what I was doing. She was fine with it... that's what she said anyway.
dipshit moderators
Actually, it was meant to make fun of the reporting that this was a major technical discovery. It seems like the folks at NASA are having routine engineering issues, yet the article makes them sound like idiots who don't understand basic electronics.
FYI, I used to be a contractor for the state of Illinois in an IT capacity. Several people I know are or have been contractors of direct employees for the state. In that particular government, I can assure you that a decent portion of the employees are incompetent, slackers, or both. The rest are hard workers who unfortunately don't have the power to change the status quo by themselves.
I'm sure there's a certain portion of the US government that suffers from the same issues (although probably not as badly). However, NASA doesn't seem like the agency in which to find incompetent slackers. The places reporting on NASA's work seem to fit the bill quite nicely, though.
I guess next time I make a joke, I'll have to include some cute little pseudo-HTML tags to let you and the mods know. Sometimes a post reads back to me as I intended it even though something gets lost in the text-only translation. Sorry.