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More Solar Panel Problems For ISS
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."
Why don't they do the repairs at night?
Or rotate the panel so that it is side-on to the sun?
If I have nothing to hide, don't search me
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.
I prefer Flambe as apposed flamebait.
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?
"We can categorically state we have not released man-eating badgers into the area." - UK military spokesman, July 2007
DUH!
Yeah because the sun Winks out every 24 hours.
I'll leave the severe beating of you to the others here.
Of course it's going to be the really shiny "NASA" kind, but still duct tape.
As for why they can't just wait for night, the period of the ISS orbit is about 93 minutes. They'd have to work fast.
See what I've been reading.
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>
Hey pal, this isn't a pleasantforest, so don't waste my time with pleasantries!
Because the night isn't very long on the ISS. From http://en.wikipedia.org/wiki/ISS: "...completing 15.7 orbits per day".
My UID is prime. Hah!
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.
668: Neighbour of the Beast
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.
I prefer Flambe as apposed flamebait.
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.
if you steal from one source, that is plagiarism, if you steal from many, well, that's just research.
(An upgrade to Hamlet's rhetorical question)
We're gonna need a bigger roll of Cello Tape.
A feeling of having made the same mistake before: Deja Foobar
yes but he is using one of the RED space suits... a sure sign he is toast.
"Slashdot, where telling the truth is overrated but lying is insightful."
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!
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.
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
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.
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.
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.
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!
He who knows best knows how little he knows. - Thomas Jefferson
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.
Because NASA Needs A Solar Array... and they are afraid of 30-Days-of-Night.... (Didn't want Halloween to become Hell-O-Ween?)
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
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?
Reinvent the wheel only at either a lower cost, greater effectiveness, or your own personal enrichment and satisfaction.
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.
and doesn't touch ground with the other, he should be fine. Wait, how does one ground himself while in space?
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.
Yes, that is a valid concern, but that is not from TFA. 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.
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.
http://www.geoffreylandis.com
Hence I said "side-on".
But, the stabilizing wires are tangled in the array, so moving at all (apparently) will tear it more.
If I have nothing to hide, don't search me
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?
Silly, the astronauts would be asleep at night. :-P
A marriage is always made up of two people who are prepared to swear that only the other one snores.
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...
... 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!
... when it comes to safety, NASA is still cutting corners!
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
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
It's one thing for astronauts to take risks, but not dumb ones that are unnecessary
End of my tirade.
Ron
He should be ok anyway. He's not earthed.
Comment removed based on user account deletion
ISS has not chassis/ground, so the free electrons are flying in the ISS's surface.
It's high electrostatic voltage and can electrocute to the mortal astronaut.
The solution is to get a hammer with plastic tick and hit the unused solar arrays.
It seems a stupid idea but it's not. It's my best found idea for the space.
Later, to cut completely the middle panel because of its broken structure.
Never! Never! Never to cut the cable!!!
Dr. Pzarro (i want US$ 0.02 to my account for this thesis iff you want warranties).
Many here voice their opinion that the space station os a waste of money. This solar panel incident has vindicated the ISS supporters: Testing such technologies in low earth orbit is a needed. You would not want to experience that on an interplanetary flight.
We may not necessarily develop new technologies but engineers can test solutions "in the field" and hone the skills needed to develop working solutions for voyages where no rescue/repair is possible.
Please, turn off the street lamps of half world.
But the enemy exists there out: the Moon!!!
http://en.wikipedia.org/wiki/Full_moon is a highly dangerous terrorist!!!
Dr. Pzarro: the unique solution is when it's http://en.wikipedia.org/wiki/New_Moon
"...since it is impossible to stop the solar panel from generating electricity during the repair attempt..."
-Er... Houston, we have a problem
-What is it now?
-you idiots forgot to install the fuse box
I've been the Linux's Quake Penguin.
http://www.wickle.com/weblog/media/Image/penguincomputing.jpg
It's a weapon made in Linux to drill the solar arrays panel.
The current moon is a brighter November's Full Moon dangerous for the this space's operation:
http://en.wikipedia.org/wiki/Hunter's_moon
The Hunter's Moon is also known as Blood Moon or Sanguine Moon.
Play to Quake to survive?
Dr. Pzarro
It's drama!
Oh! The little Asshole-nuts are going out to the far side of the space smash-ion!
A whole half of a football field away! NO! They may get electrocuted too!
oh!
Plus the fact that the whole thing is a flying garbage dump from the lowest bider.
Soon I hope the Russians start a new program that has nothing to do with nasa.
Tee minus 5 years and counting!
BM