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Pluto Probe Back To Normal, Cause of Snafu Found

Posted by Soulskill on from the just-had-to-realign-the-warp-fields dept.

Tablizer writes: NASA has provided an update to the problem with the New Horizons probe that will fly by Pluto next week. "The investigation into the anomaly that caused New Horizons to enter "safe mode" on July 4 has concluded that no hardware or software fault occurred on the spacecraft. The underlying cause of the incident was a hard-to-detect timing flaw in the spacecraft command sequence that occurred during an operation to prepare for the close flyby. No similar operations are planned for the remainder of the Pluto encounter.

17 of 80 comments (clear)

  1. No hardware or software fault? by tomhath · · Score: 4, Insightful

    The underlying cause of the incident was a hard-to-detect timing flaw in the spacecraft command sequence that occurred during an operation to prepare for the close flyby.

    So a "flaw" in the command sequence isn't a software fault? Sure sounds like one to me. Glad to hear the craft is functioning again though.

    1. Re:No hardware or software fault? by MightyYar · · Score: 4, Informative

      I'm pretty sure that "fault" has a specific meaning in NASA parlance. There was obviously a software bug, but it probably didn't "fault".

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    2. Re:No hardware or software fault? by Anonymous Coward · · Score: 4, Insightful

      There's a gap between "flawless" and "faulty" whos length, as it so happens, is remarkably similar to the distance that New Horizons has travelled so far.

    3. Re: No hardware or software fault? by MightyYar · · Score: 2

      This is not a manned mission, and not even the nuttiest nutter thinks that man is going to Pluto. You are trolling the wrong article.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    4. Re:No hardware or software fault? by 140Mandak262Jamuna · · Score: 2
      I would guess "fault" is their word for crash. This one did not crash, some audit method failed, it entered a safe fall back mode.

      Can't blame NASA though, when the commands are transmitted over 3 billion miles, the signal would degrade so much it is possible some critical command or an command argument was not correctly received.

      --
      sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
    5. Re: No hardware or software fault? by Demonoid-Penguin · · Score: 4, Funny

      Did someone who likes space shoot your mother or something? You always pop up on these threads.

      As a small child he wanted to be an astronaut. Then he heard it meant reading and, um, stuff. Bitter now, and still a child.

    6. Re:No hardware or software fault? by Tablizer · · Score: 2

      Come on NASA, was it a "fault", "snafu", "glitch", or "bug". Come clean now!

      Personally, I suspect it was a snag.

      --
      Table-ized A.I.
    7. Re:No hardware or software fault? by Will.Woodhull · · Score: 3, Insightful

      I'm guessing it was an unanticipated race condition. Everything works correctly, everything passes all tests, but for some extremely rare constellation of input values software module "B" is able to complete its calculations and report its results before "A" can-- which has a probability of occurrence so low that it rounds to zero-- and that screws the pooch. If the probability of this happening again approaches zero, it would be fair for NASA to say there was no error in the programming, but instead an unexpected glitch in operations that is unlikely to ever recur.

      You can never test for every possible corner condition. More than that, in probably every real world situation, the longer the time since the last hard reboot, the more likely it is that the software will encounter some corner conditions. That Pluto bird has been running for quite a while.

      --
      Will
    8. Re: No hardware or software fault? by MachineShedFred · · Score: 2

      Yeah, we don't like that "science" stuff around here! We'd much rather be completely ignorant of the universe around us than have you "space nutters" actually discovering things!

      Signed,

      The Flat Earth Society

      --
      Slashdot still doesnâ(TM)t support Unicode after it was added to the HTML standard in 1997.
    9. Re:No hardware or software fault? by bondsbw · · Score: 2

      Of course not. Pluto is a dwarf dog.

      --
      All my liberal friends think I'm a conservative, all my conservative friends think I'm a liberal.
  2. No exactly a SNAFU by jgtg32a · · Score: 3, Informative

    While NASA has had some spectacular bugs in the past, they aren't common enough to start throwing around SNAFU.

    Situation Normal: All Fucked Up

  3. DRINK when someone uses the word "anomaly"... by xxxJonBoyxxx · · Score: 3, Funny

    I always take a shot when someone uses the word "anomaly" in a space story. The legacy of STTNG continues.

  4. 1 sec time change? by radiumburn · · Score: 5, Funny

    Lets blame the 1 second time change - probably couldn't connect back to the local satellites because of a time certification error haha.

  5. Re:I would have done dry run of entire sequence by bobbied · · Score: 5, Insightful

    There are just some things simulations cannot find and rare "race conditions" are on that list. Of course, it all depends on how much fidelity you build into your simulation. However, at some point you have to say "Enough! If we spend any more on simulation and test we could just build and launch multiple spacecraft." So you accept the risks and move on. Race conditions are pretty hard to find in the first place, especially if they are not deterministic and only hit you every so often.

    --
    "File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
  6. 100% failure in 72 hours by gsslay · · Score: 5, Funny

    It can only be attributable to human error. They checked out the AE-35 Unit and it had no problems at all.

    I've still got the greatest enthusiasm and confidence in the mission.

  7. Re:I would have done dry run of entire sequence by AmiMoJo · · Score: 2

    The main thing is to make sure that you can recover from unexpected failures. It looks like NASA did well getting that right here.

    --
    const int one = 65536; (Silvermoon, Texture.cs)
    SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
  8. Re:I would have done dry run of entire sequence by JoeMerchant · · Score: 3, Interesting

    The fun part is when you do build and launch multiple (whatevers) and they all go down with the same "rare" fault.