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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|-
Why don't they just always try that first?
Let me guess: cosmic ray. Is it really that hard? What else causes a single bit-flip error in space?
When you have a probe billions of miles from Earth, with no hope of ever physically retrieving it, and something weird happens, I don't think the first thing you do is start making assumptions.
What else would it be?
According to some German, aliens.
W
PS is "Cosmci Ra" related to Mumm-Ra? Or She-Ra for that matter?
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This is my SIG. There are many like it, but this one is mine.
V'Ger is unwilling to just transfer the data to its Creator...
One that hath name thou can not otter
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!
Its also extremely important to note that not a single item you own is made to the specifications that Voyagers were made, even though made over 30 years ago.
Its also rather important to note that as unstable as most OSes are, they are several million times more complex than the code Voyager 1 and 2 run.
Finally, joke about Windows all you want ... if you do a default installation of Windows and you don't install any additional drivers or software, it is extremely stable and will just sit there for ages happy to do nothing but tick away.
Its also entirely feasable to find 1 stuck or flipped bit even using Java and .NET, you just have to actually understand the inner workings of this code which is not something pretty much any developer working in these environments has time to do these days.
Both things may be computers that run code and use electricity to do so, but thats about where the shared bits end. These guys have been using the same code for 30+ years ... they kinda know how it works and all its quirks at this point.
With all that said ... you're still right, its freaky impressive.
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
M-x butterfly. Cosmic rays, but on purpose.
It's pretty amazing that they even were able to track the problem down to a particular bit.
To be fair, Voyager doesn't have many bits in its memory :). Tracking down a bad bit is much easier when you have 4k of RAM than when you have 4GB of RAM.
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.
Tube testers were pretty darned hard to find almost anywhere in 1977 (you could find them in old-used-electronics stores). I do recall testing tubes in drugstores in the early 70's.
Solid state, and even (*gasp*) integrated circuits were in widespread use. Why, by gosh by golly, we even had *8080*'s then.
I was a senior in college in physics+EE; I and a handful of my fellow students managed to coerce one of the EE profs to take a few hours and teach us about tubes (they had been removed from the curriculum). For the most part the interest was for us audio-nerds... tubes had that nice desirable sweet sound... (but I digress)
Stupidity... has a habit of getting its way.
tubes had that nice desirable sweet distortion...
There, fixed that for ya...
Any sufficiently advanced intelligence is indistinguishable from stupidity.
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.
1977 - when advanced microchips were not as powerful as the chip driving the shatty calculator you buy today at the dollar store.
Classic, ever repeated confusion of what "power" is. Unless you mean volts times amps, power is what you can do with it. An old mainframe can run a department of a small multinational corporation, maybe a large university, or perhaps a division of state government. We know this, because they did in fact do so, very profitably. You claim a dollar store calculator is more powerful. That means a dollar store calculator should be able to run, say, an entire multinational corporation, maybe multiple universities, or an entire state government. Oh wait, a dollar store calculator can, at best, slowly calculate someone's income tax, possibly correctly. I guess the old mainframe is more powerful after all.
When I worked at a mainframe shop in the late 90s I heard alot of similar tiresome comments... "Ha ha, mainframes, bet you didn't know my laptop can run NOPs faster than your mainframe can run floating point FFTs ha ha ha mainframes". At which point you simply tell them to put up or shut up, hand them a bus and tag cable, and have their infinitely "more powerful" laptop process 5% of the NYSE volume like our mainframes did, while supporting about 100K trader desks, a couple TB of tape robot storage, etc.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
>>>have their infinitely "more powerful" laptop process 5% of the NYSE volume like our mainframes did, while supporting about 100K trader desks, a couple TB of tape robot storage, etc.
A laptop could do that if it had an efficient assembly-written OS (like Kolibri), rather than the bloated general purpose OSes like Windows NT or OS X. At my former company we used the equivalent of laptops (Pentium 2s) to manage, load mission data, and launch a ship full of Tomahawk missiles.
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
Classic, ever repeated confusion of what "power" is. Unless you mean volts times amps, power is what you can do with it.
Have you ever kissed a girl?
Have you ever kissed a girl?
This is the wrong place to ask for dating advice.
Exactly. The IBM 360 had a truly incredible I/O capacity, powered by multiple parallel processing elements called "channels." You programmed them with "channel command words" or CCWs. They were independent of the main CPU. When a channel needed memory, it got locked down (pfixed) and allocated to the channel, so the channel could piss into memory at high speed. Really large, thick cables connected the CPU with peripheral devices. These cables had lots of wires in them. Because lots of bits were flowing IN PARALLEL. Look up the transfer rate of a 2701 drum drive, still maintained and used for paging devices as late as the 1980's by companies who could not find anything faster.
When DEC tried to claim that they could replace 360's with VAX's, guess what happened? They didn't have massively parallel I/O processors. They didn't have a massive transfer capability. They generated an interrupt on every character typed by every user, for God's sake. They were not I/O engines. They failed, utterly. Not that VAX wasn't a good machine, but no way could it replace a 360.
How did a small 360 support hundreds of users? Why, through an innovation called "CICS." What happened was, the mainframe would fill a 3270 CRT terminal screen with a "form." You would fill in the form, locally, using the "smart" 3270's field-editing and checking capability, with no interaction with the mainframe. When you were finished filling in your form, you'd hit TRANSMIT. At which point, the variable data on your form would be glued together by the 3270 in one record and sent up for processing by the mainframe (along with everyone else's form data). A few seconds later, you'd get another form in response. Lather, rinse, repeat.
Oh wait. That's exactly how most business Web applications work. Except the screens are prettier.