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More Solar Panel Problems For ISS

Zonk posted more than 6 years ago | from the getting-a-bit-shadey-up-here dept.

NASA 118

rufey writes "This week there have been two pieces of bad news from the International Space Station. First was the discovery of metal shavings inside a problematic rotary joint used to keep one set of solar panels in the optimal position for power generation. At the close of a subsequent spacewalk, after it was relocated to its permanent location, the unfurling of the 4B solar panel resulted in it tearing in two places. A spacewalk is now planned for November 4th to attempt to fix the tear. The upcoming spacewalk is not without risks, including the remote possibility of electrocution since it is impossible to stop the solar panel from generating electricity during the repair attempt. NASA says the ripped wing needs to be fixed or the solar rotary joint problem solved before any more shuttles can fly to the space station and continue construction. With a hard deadline of 2010 for Shuttle retirement, NASA does not have much wiggle room in the schedule in order to finish ISS construction."

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118 comments

Impossible to stop the solar panel from generating (5, Funny)

Anonymous Coward | more than 6 years ago | (#21214757)

Why don't they do the repairs at night?

Re:Impossible to stop the solar panel from generat (1)

corsec67 (627446) | more than 6 years ago | (#21214785)

Or rotate the panel so that it is side-on to the sun?

Because.... (3, Insightful)

iknownuttin (1099999) | more than 6 years ago | (#21214847)

Because there's shavings in the rotary joint?

If there were an easy way to fix this, NASA would have figured it out. Don't forget, these fix rovers millions of miles away by changing computer code. I'm sure any suggestion here on /. has been thought of already.

Re:Because.... (2, Interesting)

Hemogoblin (982564) | more than 6 years ago | (#21214957)

I think you're confusing the rovers with Deep Space 1 [wikipedia.org] and it's Star Tracker.

Irrelevant to my point. (3, Insightful)

iknownuttin (1099999) | more than 6 years ago | (#21215079)

It doesn't matter. My point is the NASA folks are pretty bright people who have the ability to fix their stuff. And it amazed me that they can fix their stuff from a distance by changing computer code - regardless of what project it was.

And I know there's going to be a ton of posts implying that the NASA folks should have thought of [insert idea here]. Of course they did.

Re:Irrelevant to my point. (1)

pintpusher (854001) | more than 6 years ago | (#21215171)

And I know there's going to be a ton of posts implying that the NASA folks should have thought of [insert idea here]. Of course they did.
While I largely agree with all you've said here... Sometimes people just don't think of things, no matter how bright they are. Case in point: an actual phone call I received at 1:30 AM the other day -- "the dishwasher is stuck on and we can't figure out how to stop it". My response: um... just unplug it? "oh, heh, yeah, okay." This was from a grad student (physics) working for me part time. She's very bright and generally has practical skills too. Sometimes people just don't think of things.

Now, having said all that, is /. the place to come for that spark of genius that will save ISS? prolly not.

Re:Irrelevant to my point. (1)

Shakrai (717556) | more than 6 years ago | (#21215907)

She's very bright

No offense, but I don't think you can apply "very bright" to someone that didn't think of unplugging an electrical appliance on their own......

Re:Irrelevant to my point. (0)

Anonymous Coward | more than 6 years ago | (#21216127)

Well we have two options here. Either she is stupid for not thinking of that, or is lying. GP says she is very bright, so she must be lying. Motive? Lure him there and oops whats this on the counter? Why its a bottle of wine...

Re:Irrelevant to my point. (1)

Andrew Kismet (955764) | more than 6 years ago | (#21216165)

Sure you can. I've known everyone from Joe Sixpack to Ivory-Tower Intellectuals and in-the-real-world problem solvers to make stunning displays of stupidity, such as not unplugging an appliance, or walking away from an ATM without the money, or simply forgetting to have breakfast AND lunch and suddenly feeling hungry at 3pm and not knowing why.

Actually, I'm kinda hungry right now.

Re:Irrelevant to my point. (2, Informative)

pintpusher (854001) | more than 6 years ago | (#21216499)

brightness is irrelevant to whether someone happens to have the right synapses fire in the right order to solve a particular problem.

And that was my point. Just because someone is bright, doesn't mean they will automatically think of every solution to a particular problem. Intelligence is not a free pass to discovering stuff (though it helps a lot!).

In the case of this particular example, she had done several other things in an effort to solve the problem, any number of which were potentially viable solutions, but didn't happen to think of this particular solution.

In my experience, the solution to a particular problem can come from any number of sources, some of which aren't necessarily the expected or "sanctioned" sources. Just because someone is both intelligent and an expert in their field does *not* mean they will think of the little bit that makes for a better solution.

To swerve randomly back on topic: it is conceivable that the electrocution hazard occurs during a particularly simple portion of the repair portion that can be performed in just a few minutes. A little scheduling to ensure that this particular action occurs during ISS "night" would be a good idea, in that case. It is entirely possible that no one at NASA thought of this. It is also exceedingly unlikely that they *didn't* think of it, but it certainly makes sense for someone to speak and say "hey, maybe we should do that at night, just in case."

Sort of like (car analogy) going ahead and double-checking with the guys at the tire store "you got the lug nuts all torqued down, right?" because sometimes they forget. Yeah sure, it's their job to do that and they're the experts and no one who's not an expert should suggest it because surely they thought of that, right? But don't you feel like an idiot watching your wheel bounce down the road.

rambling...

Re:Irrelevant to my point. (2, Funny)

Single GNU Theory (8597) | more than 6 years ago | (#21217019)

But don't you feel like an idiot watching your wheel bounce down the road.

"You picked a fine time to leave me, loose wheel..."

Re:Irrelevant to my point. (1)

karnal (22275) | more than 6 years ago | (#21219939)

Apparently no one is a fan of Kenny Rogers - or his brother, Renny Kogers.

Re:Irrelevant to my point. (2, Insightful)

fbjon (692006) | more than 6 years ago | (#21217543)

The plug might be behind the dishwasher, in which case it is not immediately obvious, and definitely not a trivial solution.

Re:Irrelevant to my point. (1)

webrunner (108849) | more than 6 years ago | (#21216183)

One thing, is that someone coming from a computer or engineering background will hesitate to have "just unplug it" as a good suggestion, due to the possibility of interrupting the process causing a catastrophic failure.

Re:Irrelevant to my point. (-1, Troll)

Anonymous Coward | more than 6 years ago | (#21216563)

Yeah, but in that case it WAS a woman.

Re:Because.... (1)

Epsillon (608775) | more than 6 years ago | (#21215219)

Because there's shavings in the rotary joint?
That's a different panel. This one "just" has the two tears. The wing with the dodgy bearing is on the other end of the ISS.

Re:Because.... (1)

Rolgar (556636) | more than 6 years ago | (#21215621)

I guess that's why we've never lost an astronaut, Oh wait. . .

NASA has made errors that have killed people by ignoring somebody who got it right. Of course, the original question about working while the station was on the dark side of the earth forgets the fact that the station rotates earth in less than an hour, and few spacewalks last fewer than 3 or 4 hours.

Re:Because.... (1)

davidsyes (765062) | more than 6 years ago | (#21216057)

So, then they get to travel the world in 279 minutes... assuming a 3-hour space walk...

Re:Because.... (1)

Martin65 (166012) | more than 6 years ago | (#21216715)

Because there's shavings in the rotary joint?

The solar array with the metal shavings in its rotary joint (starboard side) is not the solar array that they are going to attempt to fix tomorrow (port side). The port side solar array rotary joint (SARJ) is functioning properly, but cannot be rotated because the damaged solar array is not fully extended, and doesn't have the proper rigidity for movement.

Re:Because.... (2, Interesting)

anexkahn (935249) | more than 6 years ago | (#21219089)

That is dangerous thing to say...It's that kind of thinking that stifles innovation...There may be an easy fix that Nasa has not thought of....like maybe covering it up the Solar panel with a blanket. who knows...

Re:Impossible to stop the solar panel from generat (3, Informative)

Boilermaker84 (896573) | more than 6 years ago | (#21216133)

The panel cannot withstand the stress of rotation while the tear exists. The spacewalk will repair the panel to the point where it can be fully extended. Once fully extended, the tension on the panel helps it withstand the stresses of rotation.

The damage to the joint affects the opposite panel.

Re:Impossible to stop the solar panel from generat (1)

Geoffrey.landis (926948) | more than 6 years ago | (#21217247)

The solar panels were designed to generate power from illumination either on the front or the back (although they are not as efficient when back-illuminated.) This allows the panels to gain a bit of power from albedo illumination (i.e., light reflected from the Earth). So turning them backside to the sun wouldn't stop them from generating power.

Re:Impossible to stop the solar panel from generat (1)

corsec67 (627446) | more than 6 years ago | (#21217313)

Hence I said "side-on".

But, the stabilizing wires are tangled in the array, so moving at all (apparently) will tear it more.

Re:Impossible to stop the solar panel from generat (0)

Anonymous Coward | more than 6 years ago | (#21214871)

DUH!

Yeah because the sun Winks out every 24 hours.

I'll leave the severe beating of you to the others here.

Blue tarp? (1)

RealAlaskan (576404) | more than 6 years ago | (#21214925)

Why didn't they take up a big blue tarp, to cover the panel and shut it down? Better yet, why not take up a big space blanket, which would be lighter and provide better shade?

As for why they can't just wait for night, the period of the ISS orbit is about 93 minutes [wikipedia.org] . They'd have to work fast.

Re:Blue tarp? (1)

davmoo (63521) | more than 6 years ago | (#21215125)

Because the tears in the panel happened while it was being re-deployed on this flight. When the shuttle launched, there was no tear to be repaired, hence no need to carry tarps, space blankets, duct tape, or anything else intended to repair a panel.

Re:Blue tarp? (2, Funny)

AndersOSU (873247) | more than 6 years ago | (#21216189)

If NASA ever goes up into space without duct tape, I've lost all faith in the space program.

Re:Blue tarp? (3, Interesting)

megaditto (982598) | more than 6 years ago | (#21216777)

Normal duct tape is probably frozen solid at 5 kelvin (or whatever the temperature is at that altitude).

In fact, I seriosly doubt that any non-magnetic glue will work well at that temp.

Re:Blue tarp? (1)

Palpitations (1092597) | more than 6 years ago | (#21218965)

Oh? [ducttapeguys.com]

I remember reading about a few of these when they happened... This is the first I've heard of Kapton tape, ("The tape is like duct tape but slippery and able to withstand both frigid cold and fiery hot temperatures."), but it looks like duct tape has played it's role in a number of ways for NASA.

Re:Blue tarp? (2, Interesting)

camperdave (969942) | more than 6 years ago | (#21215225)

Apparently [heavens-above.com] due to the inclination of the orbit, only about a quarter of those 93 minutes is in the Earth's shadow. So, the bad news is that they get slightly less than 25 shock free minutes to fix the problem. The good news is they get 15 attempts per day.

Re:Blue tarp? (1)

TooMuchToDo (882796) | more than 6 years ago | (#21217259)

Actually, they should push the shuttle launch ahead, and when the shuttle is close to the ISS, have it move in front of the panels to block the sunlight. Then someone can repair the panels without fear of being lit up like a christmas tree, as well as the possible use of both the ISS and space shuttle arms for assistance.

Please note I'm not taking any arcing effects into account here.

Re:Impossible to stop the solar panel from generat (1)

qmaqdk (522323) | more than 6 years ago | (#21214975)

Because the night isn't very long on the ISS. From http://en.wikipedia.org/wiki/ISS [wikipedia.org] : "...completing 15.7 orbits per day".

Re:Impossible to stop the solar panel from generat (1)

Ucklak (755284) | more than 6 years ago | (#21215167)

Shouldn't he be in a spacesuit when he fixes it therefore shouldn't it be extremely well insulated?

I mean, the Emperor from Star Wars should be able to blast cosmic rays at him and he should just shrug it off like morning dew.

Re:Impossible to stop the solar panel from generat (3, Funny)

falcon5768 (629591) | more than 6 years ago | (#21215257)

yes but he is using one of the RED space suits... a sure sign he is toast.

Re:Impossible to stop the solar panel from generat (1)

Gil-snowboarder (968253) | more than 6 years ago | (#21215363)

remember there are metal joints in the space suit and as he is floating inside the suit, who knows what metal he could in contact at any second.

Re:Impossible to stop the solar panel from generat (1)

ragefan (267937) | more than 6 years ago | (#21216887)

remember there are metal joints in the space suit and as he is floating inside the suit, who knows what metal he could in contact at any second.
But it is unlikely he would be grounded to anything. Just touching a charged wire, even barehanded, will not cause one to be electrocuted as long as he is not grounded.

Re:Impossible to stop the solar panel from generat (1)

Neanderthal Ninny (1153369) | more than 6 years ago | (#21215269)

Since they are in orbit and the orbital period is about 93 minutes they only have about 40 minutes "night". Why is night not evenly split between "night" and "day" is because of the when you are in orbit the extra altitude keeps you out of earth's shadow for a about 10 minutes. This is similar to if you are on top of the mountain you will notice the ground below get darker before you do and if you are in a nearly 200 miles above the surface of the earth that extra sunlight time more that a few minutes. Since the solar panels are linked together to make power together the only way is to bypass the tear. However they need to look at what happen up close to find out where to bypass it and being this close their is a remote chance of getting the capacitor affect where even you are insulated but the equipment that carries you, the remote arm, is not so you will feel the electrical force going through you. Ouch!

Re:Impossible to stop the solar panel from generat (0)

Anonymous Coward | more than 6 years ago | (#21215397)

And I wear my sunglasses at night
So I can, so I can
Forget my name while you collect your claim
And I wear my sunglasses at night
So I can, so I can
See the light that's right before my eyes

Re:Impossible to stop the solar panel from generat (3, Insightful)

Anonymous Coward | more than 6 years ago | (#21215435)

Mod parent insightful, not funny, as it is valid question, and was indeed asked ("why not limit the the repair time to night passes") on yesteray's NASA's mission status briefing. The response was that sacrificing basicly spending half of the spacewalk to do nothing is not worth the added safety - note that the 'electrocution' mentioned is very extreme case, as the panels itselves are coated with insulation, the tools are insulated etc, but as they spend years in space and were damaged, there is concern that there *might* be some scratch in the coating or anything, that *may* conduct, and it *may* touch some of the EVA equipment, and that *may* conduct through the electronics (the space suit is full of sensors and stuff that touch the body), and it *may* go through the heart of the astronaut, and in really really extreme case that *may* end up with electrocution. Of course that word was immeidately picked up by the press, and it ended up with the staff saying that if on of the reporter in the room leaned back to his microphone, that there is about equal chance he may be electrocuted.

Re:Impossible to stop the solar panel from generat (1)

noidentity (188756) | more than 6 years ago | (#21215707)

On a more serious note, don't the solar panels have switches to disconnect them from each other? They are like batteries connected in series, so you just need to break a few connections to lower the voltage and make each subset electrically floating with respect to the others. It's like when you were little and connected a bunch of 9V batteries together and got a big shock.

Re:Impossible to stop the solar panel from generat (1)

davidsyes (765062) | more than 6 years ago | (#21215805)

Because NASA Needs A Solar Array... and they are afraid of 30-Days-of-Night.... (Didn't want Halloween to become Hell-O-Ween?)

Re:Impossible to stop the solar panel from generat (2, Funny)

Odin's Raven (145278) | more than 6 years ago | (#21217935)

Why don't they do the repairs at night?

Silly, the astronauts would be asleep at night. :-P

Re:Impossible to stop the solar panel from generat (0)

Anonymous Coward | more than 6 years ago | (#21218553)

He should be ok anyway. He's not earthed.

Deadline (4, Interesting)

ktappe (747125) | more than 6 years ago | (#21214855)

Why is 2010 such a "hard" deadline? Was it not created solely by politicians who wanted to divert resources to go to Mars? As such, can it not be moved just as easily as it was created? It is, after all, three years away. If we can't move deadlines that far out, isn't there a chance we're overplanning, and leaving ourselves completely vulnerable to unexpected circumstances, exactly like this solar panel issue?

Re:Deadline (2, Funny)

iknownuttin (1099999) | more than 6 years ago | (#21214977)

Why is 2010 such a "hard" deadline?

Because they missed 2001.

Re:Deadline (0)

Anonymous Coward | more than 6 years ago | (#21217099)

I guess the next opportunity after 2010 will be a poor attempt in 2061.

With apologies to fans of Arthur C. Clarke.

Wow, has Slashdot added a spell checker? I've a red line run under Clarke.

Re:Deadline (1)

GreggBz (777373) | more than 6 years ago | (#21215063)

Remember "Man on the Moon by the end of this decade?"

Nothing motivates like a deadline. It may seem arbitrary, but NASA is doing lots of good, hard work on the ISS these days, and I think maybe that's because the pressure's on.

Re:Deadline (5, Informative)

DerekLyons (302214) | more than 6 years ago | (#21215107)

Why is 2010 such a "hard" deadline? Was it not created solely by politicians who wanted to divert resources to go to Mars?

No, it was created by the CAIB subsequent to the loss of Columbia.
 
 

As such, can it not be moved just as easily as it was created?

No, because the CAIB requires the vehicles be recertified to extend their lives beyond that date - a very expensive and difficult process.
 
That being said - another limit, currently, is contractural. NASA has only contracted for so many External Tanks, SRB refurbishments, etc... Unless Congress coughs up more money (and approves the delays in converting facilities to support Ares/Constellation - I.E. more money) it simply isn't going to happen.
 
 

It is, after all, three years away. If we can't move deadlines that far out, isn't there a chance we're overplanning, and leaving ourselves completely vulnerable to unexpected circumstances, exactly like this solar panel issue?

NASA routinely plans from 3-5 years out, to a decade or more. This is made necessary by the fact that planetary launch windows, if missed, may not recur for two years (Mars) or two _centuries_ (Pluto). Also, the hardware takes from months to years to assemble, on top of months to years of design and review effort. Training for a flight takes months. The Shuttle also has to be overhauled so often, a process taking months, so you have to plan ahead to make time available for that. Etc... Etc...

Re:Deadline (0)

Anonymous Coward | more than 6 years ago | (#21217561)

"NASA must complete the ISS so it can be dropped into the ocean on schedule in finished form." --Robert L. Park, Professor of physics at the University of Maryland, College Park and a former Executive Director of the American Physical Society.

Hope they brought the duct tape... (5, Funny)

sgv-0027 (1183425) | more than 6 years ago | (#21214903)

Of course it's going to be the really shiny "NASA" kind, but still duct tape.

Re:Hope they brought the duct tape... (1)

Anne_Nonymous (313852) | more than 6 years ago | (#21215015)

>> the really shiny "NASA" kind, but still duct tape

I think it's some of that special 7.7 km/second duct tape. [esa.int]

Away Team extra crewman (5, Funny)

RealGrouchy (943109) | more than 6 years ago | (#21214933)

He will not be electrocuted, or at least if he is, he will survive.

Of all the crewmembers aboard the ISS/Space Shuttle, Parazynski is the most experienced.

If NASA were going to kill off a character, they'd send out one of the junior redshirts to do the repair job.

- RG>

Re:Away Team extra crewman (1)

MyLongNickName (822545) | more than 6 years ago | (#21215003)

He will not be electrocuted, or at least if he is, he will survive.

By definition, electrocution means death. It is one of those misused words of the English language.

Re:Away Team extra crewman (1)

G Fab (1142219) | more than 6 years ago | (#21215249)

either that or the language has changed and the people who think they can decide what the english language is are being stubborn.

Language isn't something you find in a book.

Re:Away Team extra crewman (0)

Anonymous Coward | more than 6 years ago | (#21215555)

either that or the language has changed and the people who think they can decide what the english language is are being stubborn.

Right. Also, yakka foob mog, grub pubbawup zink watoom gazork. Chumble spuzz.

Oh, did you want me to keep using the language rules that YOU approve of?

Re:Away Team extra crewman (0)

Anonymous Coward | more than 6 years ago | (#21215781)

Excuse me sir, perhaps you need to revisit 3rd grade grammar. It should be "Chumbla spuzz". Subject/verb agreement and whatnot.

Re:Away Team extra crewman (0)

Anonymous Coward | more than 6 years ago | (#21215651)

Language is like, subjective man. You can't tell people to obey the rules of grammar or language. That's like telling Gene Krupa no to go "boom boom bam bam bam, boom boom boom bam ba ba ba ba".

Re:Away Team extra crewman (1)

RealGrouchy (943109) | more than 6 years ago | (#21215773)

D'oh!

Thanks. In that case, I guess that makes "if he is, he will survive" a pretty big "if"!

- RG>

Re:Away Team extra crewman (2, Funny)

BytePusher (209961) | more than 6 years ago | (#21216817)

By definition, electrocution means death. It is one of those misused words of the English language.

What's a better word that leaves no ambiguity? Shock, needs to be specified and the wording will be awkward as it sounds odd to say he will be "electrically shocked," or could experience "electric shock." The etymology of the word from dictionary.com says is came from "electric" + "(exec)ution." It's clever, because it provided nearly an instantaneous and seamless integration into the English language since execution already has it's conjugates defined. However, I have not seen anyone who complains about the misuse of "electrocution" providing a clever, easy to say, quickly understandable alternative. So, please, find or invent a word that is more suitable than electrocution.

Here are my alternatives:

Electrinjury: Electric shock resulting in injury.

Electeleportation: Electric shock resulting in teleportation.

Electrouch: Electric shock resulting in an "ouchie."

Re:Away Team extra crewman (1)

davidsyes (765062) | more than 6 years ago | (#21216131)

So, will he return to Earth as V'Ger? Or, will he come back as Nomad, seeking one Jackson Roykirk. In either case, he'll probably return to "eliminate carbon-based infestation"... Yikes... Is this a job for Shatner, or will he just holler "Khhhaaaaannn!"?

Purple-headed demon (-1, Troll)

Anonymous Coward | more than 6 years ago | (#21214941)

Stretch that anus!

BTW: NASA is a totally worthless waste of money... Money that should have gone towards the Iraq war effort, for instance.

Simple Solution (-1, Troll)

Anonymous Coward | more than 6 years ago | (#21214979)

Get the people off the ISS and de-orbit it. When the Space shuttle is retired and the ISS is de-orbited, then NASA could be abolished Then we would have more money for the social programs so deparetly needed without having to raise the taxes.

D'oh! (3, Insightful)

PHAEDRU5 (213667) | more than 6 years ago | (#21215023)

Good luck to them. I hope all goes well, the repair is made, and nobody gets hurt.

That bit about not being able to take it down for repair, well, that's going to make it into some future book on industrial design. Oh, and into future space stations. I hope.

Re:D'oh! (4, Insightful)

everphilski (877346) | more than 6 years ago | (#21215335)

That bit about not being able to take it down for repair, well, that's going to make it into some future book on industrial design.

Pray tell, short of covering the solar array from view of the sun, how do you stop solar cells from generating electricity? It is a passive electricity generating device, not an active one (like a fuel cell or a conventional gas-powered generator). As long as it has a sufficient view factor of a light source, it generates electricity.

Re:D'oh! (1)

PHAEDRU5 (213667) | more than 6 years ago | (#21216175)

I think you just answered your own question.

Re:D'oh! (0)

Anonymous Coward | more than 6 years ago | (#21217103)

What happens to a solar cell in full sunlight, but connected to an open circuit? Does it just heat up instead of pushing electrons?

I assume it's naive to think they can just open the circuit and be safe. If the space walker touched the wrong two points, they could still short across themselves.

Re:D'oh! (1)

TooMuchToDo (882796) | more than 6 years ago | (#21217319)

You have your transport vehicle (i.e. the shuttle) position itself between the light source (i.e. our sun) and the generation system (i.e. the panels) during repair. Last time I checked, the shuttle had a fairly wide body.

Re:D'oh! (1)

iamlucky13 (795185) | more than 6 years ago | (#21218303)

The shuttle is docked to the station and will remain there until the end of mission. Undocking and redocking the shuttle is a lengthy procedure. It also has some potential for causing movement of the station, and if they're concerned about exacerbating the damage simply by rotating the joint, then, a less controlled motion due to undocking is most certainly a no-no.

Conducting an EVA around the ISS with the shuttle in motion is literally placing the astronauts (mass: 200 kg) between a rock (shuttle - mass: 100,000 kg) and a hard place (ISS - mass: 270,000 kg). Not to mention, as the undocked pair orbited from one side of the planet to the other, the shuttle would naturally tend to drift from one side of the array to the other, passing through the array unless the pilot constantly adjusted the position with the thrusters. That probably wouldn't fly as a properly planned EVA with months of orchestration, training, and other preparation. It certainty wouldn't fly as a scraped together barnstorming written on the back of a checklist a la Apollo 13 unless there was an imminent threat.

In fact, the threat can hardly be very substantial. The nominal voltage of an entire solar cell string is 160V...a little bit less than the peaks in 120 household VAC. According to NASA, the voltage can get as high as 320V. The astronauts are wearing thick suits, and while electrical protection probably wasn't particularly high on the list of design criteria, they certainly weren't designed to be conductive.

Of course, NASA is being careful to minimize any danger to the astronauts, but I imagine the far greater concern is an electrical short damaging some hardware, especially in the robotic arm. I highly suspect the article has over-emphasized the risk and we're getting hung up on something that's nearly a non-issue.

If I were one of the astronauts, I'd be much more concerned about the plan to get out there in the first place, since this tear would normally be out of reach. It involves the station robotic arm grabbing a part of the shuttle robotic arm like a baseball bat and dangling the astronaut out at the end of this orbital fishing pole.

Re:D'oh! (1)

RealGrouchy (943109) | more than 6 years ago | (#21217469)

It's simple. All they have to do is unplug it!

- RG>

Re:D'oh! (0)

Anonymous Coward | more than 6 years ago | (#21219495)

I don't know. Maybe give it to Con Ed?

Re:D'oh! (1)

SomeRandomWag (933715) | more than 6 years ago | (#21219965)

Danger from the generated electricity? As I understand it, these panels only have one active side - rotate the sucker 180, point the passive side towards the sun, and away you go?

4B or not 4B (2, Funny)

ackthpt (218170) | more than 6 years ago | (#21215183)

(An upgrade to Hamlet's rhetorical question)

We're gonna need a bigger roll of Cello Tape.

hard deadline of 2010 for Shuttle retirement (0, Flamebait)

bsharma (577257) | more than 6 years ago | (#21215479)

That also implies hard deadline for ISS usefulness. Even with the Shuttles, hardly any science was done beyond assembling the ISS. Without Shuttles, it would be very risky even to maintain an operating ISS, let alone do science. ISS was one big 100 Billion $ motel-in-space. Complete waste of money - if you ignore "lessons learnt" in fabricating large extra-terrestrial structures.

Re:hard deadline of 2010 for Shuttle retirement (0)

Anonymous Coward | more than 6 years ago | (#21217425)

Does anyone know of some good science done at ISS?

Re:hard deadline of 2010 for Shuttle retirement (1)

Mr. Picklesworth (931427) | more than 6 years ago | (#21220055)

Why would we ignore lessons learned there? That sounds like a creationist saying there is no proof of evolution if we ignore that fossils can be dated.
Of course I would share your sensationalist, pessimistic opinion if I chose to ignore anything that proved me wrong, but I won't. I definitely wouldn't make it known that I am intentionally ignoring those details, though...

-How to build a facility in space where one can safely live for time measured in months.
-How to manage the construction of an international facility with contributions from space agencies in many countries. Open source people should be interested in that...
-Why spacecraft should be examined closely after launching from Earth
-How to carry out complex construction projects without the luxury of a plentiful energy source (gravity)

It's still under construction, and a lot of the scientific modules are still scheduled to go up, so of course there hasn't been much science yet!
That isn't to say there isn't any, mind. There has been quite a bit of learning about how humans are affected by the lack of gravity in space. Wait for the station to be complete, then 5 years of full use later, and make that claim.
Nobody commented about the Empire State Building not being really tall when it was only three quarters through construction. What's different here?
Patience, grasshopper.

Electrocution? (2, Interesting)

Radon360 (951529) | more than 6 years ago | (#21215481)

including the remote possibility of electrocution since it is impossible to stop the solar panel from generating electricity during the repair attempt

Forgive my ignorance, but are they going to do this spacewalk repair bare-handed? Is there at least two exposeds part of a spacesuit that is conductive from the outside to the inside (you need two points to complete a circuit)? If there's something like aluminum ring seals at the wrists, have another crewmember double wrap them with duct tape or electrical tape before sending them outside.

How does electrocution come into play with this? Dielectric breakdown through the suit shouldn't be an issue as I seem to recall on a previous story that we're talking roughly 160VDC potential, nearly the same as US household wall socket voltages. Deadly? Yes. Arc through your spacesuit (twice)? Hardly.

Re:Electrocution? (0)

Anonymous Coward | more than 6 years ago | (#21215951)

Call me crazy, but I'm gonna take a wild ass guess that the guys doing this for a living know a little bit more about it than you do.

Paraphrased from http://www.space.com/businesstechnology/ap_060803_exp13_fpmu.html [space.com]

The space station picks up electrons and ions as it flies through a thin layer of the Earth's atmosphere, said professor Charles Swenson, who had a key role in developing the Floating Potential Measurement Sensor Unit.

"It's similar to picking up a charge and getting extra charge particles on your body," he said. "If you touch a doorknob they jump off your body."

NASA is concerned that charges on the solar panels of the space station will jump to another side of the station or even to an astronaut's suit, Swenson said.

The suit could be damaged, or an astronaut electrocuted, if a charge jumped from the station to the metal rings on a suit.

"They are in a sweaty, wet garment inside the suit, not very conducive to working in a high-voltage environment," Swenson said.


More detail on what happens, and steps NASA takes to mitigate the risk.
http://space.newscientist.com/article/dn9669 [newscientist.com]

Re:Electrocution? (0)

Anonymous Coward | more than 6 years ago | (#21216005)

Just watched Friday's mission briefing. Actually some sort of "overgloves" will be used, just in case.

Re:Electrocution? (3, Informative)

rbarreira (836272) | more than 6 years ago | (#21216035)

Did you read the article?

Flight controllers have already warned Parazynski not to touch the electricity-generating solar cells that cover virtually the entire wing. If the metal of a tool he was holding melted, it could burn a hole into his glove.

Re:Electrocution? (1)

Radon360 (951529) | more than 6 years ago | (#21216399)

But wouldn't result in a burn injury or the risk of death due to decompression and not electocution?

Maybe I'm being too pedantic on the definition of electrocution, which is death from electric shock, not death resulting from some failure caused by an electrical discharge.

Re:Electrocution? (1)

rbarreira (836272) | more than 6 years ago | (#21216651)

No, I don't think you're being too pedantic. Maybe this [slashdot.org] is the answer?

Blame the summary. (1)

Radon360 (951529) | more than 6 years ago | (#21216921)

Yes, that [slashdot.org] is a valid concern, but that is not from TFA [msn.com] . In fact, the only mention of electrocution comes directly from the slashdot editor's/submitter's summary:

including the remote possibility of electrocution since it is impossible to stop the solar panel from generating electricity during the repair attempt.

The above quote rather explicitly attributes the danger of electrocution from electricity being generated from the solar panel, not the discharge from static build up.

The short of it (no pun intended): Electrocution from the electrical current from the solar array? No. Electrocution due to a static discharge? Possibly yes, but it's not the source of the lethal electricity alluded to by the summary.

Re:Electrocution? (1)

OdinOdin_ (266277) | more than 6 years ago | (#21216209)

Gee... while it might not electrocute the astronaut, it might zap his space suit control system and his life support, or conduct down the robot arm boom he is standing on and end up taking out a system in the ISS (or the robot arm itself). Its a very real danger for everyone up there.

AC/DC (1)

toddhisattva (127032) | more than 6 years ago | (#21217811)

160VDC potential, nearly the same as US household wall socket voltages.
DC is as different from AC as black is from white black white black white black....

Re:Electrocution? (1)

Agripa (139780) | more than 6 years ago | (#21220039)

There is a significant environmental difference when you deal with powered circuitry in a vacuum verses an electrically insulating atmosphere. The space station not only travels through a good vacuum but any gases present will tend to be an an ionized state and conduct so it is not necessarily a matter of avoiding physical contact from the panel to a conductive area of the space suit.

I suspect the best defense would be a conductive suit similar to that worn by linemen who work on power lines. I do not know if the space suits have a conductive layer for protection but if they do it is possible it was not intended for an ionized space environment that includes exposed high power 160 volt circuits.

Perpetual power generation you just can't turn off (3, Funny)

digitaldc (879047) | more than 6 years ago | (#21215603)

The partially unfurled solar wing is producing power, and there is no way to turn it off

Man, do we need one of these things on Earth, RIGHT NOW!

Electrocution? (1)

hcdejong (561314) | more than 6 years ago | (#21215911)

Simple solution: make sure his tether is non-conducting. Use one of those MMUs so the astronaut can be autonomous instead of on an umbilical. Or am I overlooking something?

Re:Electrocution? (2, Informative)

Zerbey (15536) | more than 6 years ago | (#21216327)

The fact that the MMU hasn't existed for over 20 years? NASA discontinued the project as being too risky with little benefit.

Re:Electrocution? (1)

Grandiloquence (1180099) | more than 6 years ago | (#21216363)

Even better - route all the power from the solar array through the deflector dish! That way there won't be any power left to electrocute. It always worked on Star Trek...

Re:Electrocution? (1)

Interl0per (1045948) | more than 6 years ago | (#21216387)

The panel contains both the charged and grounded elements required to induce current, it is only necessary to get a hold of each of those sides (such as grabbing exposed conductor in both hands) to make a perfect circuit across your chest. It only takes something less than 1 Amp to stop the heart IIRC. As the previous post said, though, the risk is minimal and these things are done to the limits of safety (we hope).

Re:Electrocution? (0)

Anonymous Coward | more than 6 years ago | (#21218421)

Actually, he needs a conducting tether to ground himself to the ISS. If he's simply floating it's possible for him to build up a charge of thousands of volts relative to the station. Then, the instant he touchs anything, solar cell or otherwise...

Travelling through space the station builds up a similar charge relative to the earth. To prevent hazardous discharges akin to lightning, especially when potentially differently charged spacecraft are approaching to dock, it has a device which ionizes helium and sprays it into space to get rid of excess electrons or protons.

Electrocution? (0, Redundant)

syukton (256348) | more than 6 years ago | (#21216063)

The upcoming spacewalk is not without risks, including the remote possibility of electrocution since it is impossible to stop the solar panel from generating electricity during the repair attempt.
So they can't just turn the panels away from the sun...why? Or unfurl some sort of mylar shield? What kind of amateurs designed a system that can't be turned off for maintenance?

Blame Lockheed Martin (1, Interesting)

Anonymous Coward | more than 6 years ago | (#21216321)

Jerkoffs from Lockheed Martin designed these problem-plagued arrays. Furling/unfurling the arrays has been a problem from day one. Recall the problems the HST had with array warping? They were designed by the same idiots at Lockmart. The problems went away after the last shuttle servicing mission when NASA installed proper rigid Boeing arrays.

Re:Blame Lockheed Martin (1)

Lord Ender (156273) | more than 6 years ago | (#21216765)

Well, I guess we all know which company you work for.

Re:Electrocution? (1)

maciarc (1094767) | more than 6 years ago | (#21217723)

Can't they do this at night? I don't know of an orbit that would have them in daylight 100% of the time.

As long as he makes repairs with one hand ... (2, Funny)

aphexcoil2 (878167) | more than 6 years ago | (#21216233)

and doesn't touch ground with the other, he should be fine. Wait, how does one ground himself while in space?

Re:As long as he makes repairs with one hand ... (1)

NeilTheStupidHead (963719) | more than 6 years ago | (#21218037)

I would assume the same way you ground something in a car, which is isolated by rubber tires: a large mass of metal, usually the body or engine (or both), serves as the ground.

Budget for replacement parts (1)

heroine (1220) | more than 6 years ago | (#21217359)

At the rate things normally break and the lack of a budget for replacement parts, exactly what do they expect to work in 2010 when construction ends?

NASA Neglecting Lock Out and Tag Out Procedure (0)

Ron Bennett (14590) | more than 6 years ago | (#21218333)

If any of the astronauts get seriously shocked or even killed, NASA managers are going to wish they had followed basic electrical safety precautions in an industrial environment, which the ISS is...

Lock Out and Tag Out electrial safety procedure - something NASA should be following - imagine the public and political outrage, if someone is seriously injured / dies as a result of skipping some basic safety precautions like turning off that solar array...

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

While it's true that in some instances electrial repair is done on live wires / devices, that's typically done by people with much electrial experience wearing specialized safety gear ... the astronauts have neither of those things - little to no experience with electricty and no safety gear designed for live electrial work - in short, work on a live solar array without the proper training and gear is reckless!

It's one thing for astronauts to take risks, but not dumb ones that are unnecessary ... when it comes to safety, NASA is still cutting corners!

End of my tirade.

Ron

Re:NASA Neglecting Lock Out and Tag Out Procedure (3, Informative)

Anonymous Coward | more than 6 years ago | (#21218663)

If you read the article, in fact if you had merely completely read the summary, you would understand that solar panels can not be turned off. Even in the absence of direct sunlight (which only occurs for a maximum of 36 minutes each orbit) they will still develop some power due to reflected light. You would also have noted that electrocution is a "remote risk."

If the problem were anywhere downstream of the sequential shunt units, they could lockout/tagout (btw, there is no OSHA in space), but it's upstream.

This is not design negligence. It's a fundamental fact of photovoltaics.
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