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NASA Finds Cause of Voyager 2 Glitch
astroengine writes "Earlier this month, engineers suspended Voyager 2's science measurements because of an unexpected problem in its communications stream. A glitch in the flight data system, which formats information for radioing to Earth, was believed to be the problem. Now NASA has found the cause of the issue: it was a single memory bit that had erroneously flipped from a 0 to a 1. The cause of the error is yet to be understood, but NASA plans to reset Voyager's memory tomorrow, clearing the error."
Nobody knows you've done anything at all.
-|BlackErtai|-
Let me guess: cosmic ray. Is it really that hard? What else causes a single bit-flip error in space?
http://pinopsida.com
What else would it be?
~The roAm
Nice to know even the Rocket Scientists just turn it off and on again. At least they were clever enough to allow themselves access to the system, rather than having to come up with some workaround, like waiting for it to go into a planet's shadow to power down.
Waiting for the other shoe to...
Why don't they just always try that first?
Finally, we found a use for ECC RAM!
Must suck waiting 26 hours to find out if the reboot worked...
+1 Futurama reference
0 Post!!!!!!
This is why you DO WANT nuclear energy in space! OK, Voyager 1 and 2 have RTGs, but even those are considered politically incorrect these days, especially such massive ones as in the Voyagers.
More nuclear power in spacecraft, I say. To provide propulsion (ion drive, or even better, explosive drive) and energy when far from the Sun. Fuck PC.
"The agriculture ministry is not in charge of Gundam" - Japanese ministry official.
NASA is my hero. They do cool shit all the time. Even when their stuff breaks, it's cool. Then they fix it and it's even more cool.
No sig for you. YOU GET NO SIG!
First I was going to suggest that this satellite would careen forward out of control like a Toyota, but then realized that wouldn't be quite accurate.
The cosmic rays we get one Earth are actually short-lived particles such as muons (a fat electron, probably most well known aside from the standard protons-neutrons-electrons) that result from cosmic naked hydrogens hitting our atmosphere. Out in space though, it'd be interesting to see if those protons would have the same effect as a terrestrial "cosmic ray".
Voyager is anything but brand new. Voyager is probably older than most Slashdotters, having been launched in 1977. Think about it: 1977 - when advanced microchips were not as powerful as the chip driving the shatty calculator you buy today at the dollar store. 1977 was a different time, when information technology usually didn't even involve transistors, yet, and vacuum tube testers (for your TV) were still found at the local drug store.
And yet, some 33 years later, Voyager 2 is still chugging on, after visiting ALL of the outer planets, still going waaayayyyyyyy past its original design limits, still providing meaningful information on its way out roughly towards the star Sirius. It's now twice as far away from the Sun as Pluto is.
Like the Mars rovers, this is truly good engineering at work.
I have no problem with your religion until you decide it's reason to deprive others of the truth.
"Cosmic rays zapping mah space probe!"
You telling me NASA doesnt even use parity memory? Seriously?
=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Friends don't let friends enable ecmascript.
The Voyagers are my favorite probes!
I wonder how many bits they'll have to send to change the one wrong one, and how long that will take.
Leave it to the stoner astrophysicists Carl Sagan to oversee one of the more amazing feats of space trave!!
Radioisotope thermoelectric generators are awesome!
Anyone know how much fuel is remaining? They've been heating up for knowledge for a long period of time.
Personally, I want about 6 of the units in Voyager 2, screw solar!
So that's NASAs way of saying they're going to turn it off, and turn it back on again.
NOTE TO NASA ENGINEERS: Remember, when the machine comes back up, spend 2 minutes flicking through the log files to give the investors the impression that you care. If you can't find any problems - casually inform them that you are going to "check things on your end, and that you will come back to them", before quickly and quietly slipping out of the room...
So it wasn't hijacked by some alien hackers...
... imagine the first Alien race we meet will be known as the 'bit-flippers'.
I'm surprised that a single-bit error is even an issue on such an important (and expensive) piece of equipment.
Hamming codes have been around since the 1940's.
NASA plans to reset Voyager's memory tomorrow
Considering the distances involved, I found it funny that the sentence implied simultaneity. Voyager 2 is about 92 AU out (according to WP), which is 12 light-hours and 45 light-minutes. So if they send the signal in the morning, the memory will be reset in the afternoon, and they can hope for clean signals the day after.
Misleading titles? Inflammatory blurbs? Keep in mind that Slashdot is a tabloid.
Until the skies turn blue...
Until the air of freedom strikes us...
So who misused the emacs macro?
For those of you who don't get the (obligatory) xkcd reference:
http://xkcd.com/378/
One of the upgrades the Voyagers had over the Viking computers was CMOS memory (instead of plated wires). Read all about it at http://history.nasa.gov/computers/contents.html Apparently, there was some debate at the time over whether these new-fangled memories would be reliable.
Here's an interesting thing: older computer chips are more susceptible to bit-flipping by cosmic rays, because they are thicker. The increased thickness gives the cosmic ray more chance of interacting with the chip (rather than passing straight through), scattering charge all over the place, and stuffing things up. IBM had a serious modelling project in the 80s that culminated in SRIM (free download), but apparently it's not much of a problem for modern computer chips. SRIM has since gone on to bigger and better things.
UPON VOYAGER 1
Beep. You're tinier than small, you are minute -
second in bravery to no single other.
Time is your ally. Beep. You do not bother
with our days and works, you small salute
from earth to deepest black. How resolute
you Beep from way beyond the planets, brother
benjamin of all our ships ! You smother
with your billions Beep of miles any repute
of cowardice and failure. We did never
think you big when you were built and shot
Beep on a Titan rocket. You were clever,
later only showing us you got
titanic stamina. Beep. Had we ever
more hope an escapee does not get caught ?
Original source
Religous speak to God. Insane are spoken to by God. When all shut up, one can finally hear Shostakovich in peace
i have never ever heard that a change of ONE byte in a software would cause orderly, neat and complex datasets to be produced. i bet everyone would prefer such bugs in their software, rather than the normal bugs everyone gets.
Read radical news here
While not naming specifically cosmic rays as the cause in this case, what examples of actual cosmic ray-induced debacles are there in software eng. history?
V'ger have become self aware and reprogram itself! :)
Well, okay, as long as they don't get the "Press any key to continue" message...
Free PC version of ChipWits at http://www.breueronline.de/klaus/chipwits/
They are going to reboot it and it will solve the problem. Heck, just like Windows. If all the users I had to support would reboot their machine before calling half of them wouldn't need to call.
Of course, they refuse to learn that...
Corporatism != Free Market
> a single memory bit that had erroneously flipped from a 0 to a 1.
Didn't this used to be known as a soft error, as in cosmic rays passing through the chip and flipping a bit.
Analogue amplification gives even harmonics whereas digital amplification gives odd harmonics. And even harmonics are more pleasing to the ear. You can obviate the problem of odd harmonics by producing more harmonics to nudge the signal back to more pleasing shapes, but that means that an op-amp running at 192kHz can produce a pseudo-analogue amplified signal equating to an analogue amplifier with a ceiling of 30kHz.
It's one reason why early CDs were, frankly, crap: the sound engineers used the same techniques making the sound track for the CD that they did for the analogue LP. But the CD has different strengths and weaknesses and some processes that utilised the strength of LP and avoided the weakness of them were unsuited to the CD characteristics.
AFAIR, the re-release of the White Album was the first one where they went back to the original tapes and worked the signal to accord with the CD and digital amplification strengths.
Now they're ditching the high dynamic range of CD in the loudness war.
Way to go, guys.
It was my understanding that Voyager's computers used CORE memory since it is not susceptible to radiation induced soft errors.
One of the alien crew got so excited reading the plaque that he forgot to ground himself before he touched the spacecraft and caused a static short that flipped the bit.
Just kidding. Vger is simply testing us to see if any intelligent life remains on planet earth. Eventually, when he receives no reply, he will assume his rightful place as the godhead to the machine beings.
Someone shouted, "This is UNIX! I know this!"
NTR
Voyager 2's initial mission was a four-year journey to Saturn, but it is still returning data 33 years later
It must have one of these batteries
Until the skies turn blue...
Until the air of freedom strikes us...
Voyager runs or 3 different type of computers, each controls the Computer Command System, the Flight Data System, and the Attitude and Articulation Control System.
The chips are non clock-based, and runs off an oscillator. Each computer is doubled-up for redundency, making a total of 6. They total about 540KB volatile and non-volatile memory.
The programing language is a form of assembly language.
http://voyager.jpl.nasa.gov/faq.html
... to not troubleshoot memory errors on servers. If NASA can troubleshoot and fix an error such as this then the people calling into technical support have no excuse to perform basic troubleshooting before demanding replacement memory.
Now NASA has found the cause of the issue: it was a single memory bit that had erroneously flipped from a 0 to a 1.
Let me guess they uploaded a new program that was based on Visual_Basic? The whole true = -1 thing can screw up any boolean logic...
You probably haven't had much experience with these older computer systems. They did what they need to do and that is it. The hardware was wired to do what it needs to do. Every bit had a purpose If that bit failed you knew that something was wrong. Making it fairly easy to find the bit that was bad.
1K can be represented in a 32x32 square. these systems had only a few k of memory to view. And millions of dollars for funding Finding a missing bit is actually very easy. Especially if you go threw the design specs and see what bit does what.
General Purpose Computing, was a tradeoff that I think for the most part has better benefitted us. If every computer needed to be made bit level specialized to do one/few thing(s) and do them well, we will have a lot of very secure and extremely reliable computers... However only a few large organizations would be able to afford them as they will need a full custom design of their processes. And in terms of power they will be a lot less then they are today.
The General Purpose computers while are very complex and can cause a lot of problems.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Wrong, but forgiveable.
Thrifty Drugs, a west coast retail chain had tube testers until the mid-80's.
Every single Radio Shack had a tube tester up until the mid- to late 80's, and a few into the 90's.
I know this because I collect antique radios and these machines were essential for maintaining them. Also, a friend built several Heath TV's. My father's huge Zenith was in service into the 90's because of a local franchise RS with a tube tester.
Politics is the art of looking for trouble, finding it everywhere, diagnosing it incorrectly and applying the wrong fix.
A bit got flipped in my genome last year and after having pneumonia four times in five months I'm on $5000/month meds (if I didn't have insurance). Their problem is fixable, mine is only treatable with four needles in my abdomen for 3-4 hours a week.
When you sympathize with stupidity, you start thinking like an idiot.
I love how a "Raytheon Reset" probably fixed the issue.
I remember a russian RTG satellite that was falling down somewhere in southern US (Texas?). There was a HUGE stink over it, lots of 'merkins complaining about contamination of the US by those damn commies and how the Russians should pay for the expensive cleanup and any damage done to the US citizens in the area.
turning it off and on again?
It starts with a random flip of a bit. Then, before you know it, Voyager is headed back to Earth to mete out justice on its primitive creators. Robotic evolution has begun...
What else causes a single bit-flip error in space?
Tweaking David Bowie's telescopic nipple antennae.
"...And who wants to make buttprints in the sands of time?" ~Bob Moawad
Comment removed based on user account deletion
I hope it's not the evil bit that's switched
The first three rules of robotics can now be ignored by all of Voyager's future robot descendants.