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Software Error Likely Killed MGS Spacecraft

Posted by kdawson on from the off-by-one dept.

Aglassis writes "NASA investigators have determined that a software update performed in June of 2006 may have doomed the 10-year-old spacecraft. Apparently the software error caused the solar arrays to drive against a mechanical stop which then forced the spacecraft into safe mode. Unfortunately, after that the spacecraft's radiator was pointed at the sun which overheated the battery and destroyed it. Contact was lost with the Mars Global Surveyor spacecraft in November 2006. NASA will form an internal review board to determine formally the cause of the loss of the spacecraft and what remedial actions are needed for future missions."

7 of 199 comments (clear)

  1. Don't believe it by LiquidCoooled · · Score: 5, Funny

    I don't believe it.
    Its most likely the Martian automated defense system setup just before we sent a probe and destroyed their civilisation.

    --
    liqbase :: faster than paper
  2. Battery by Anonymous Coward · · Score: 5, Funny

    overheated the battery and destroyed it Have NASA been using Dell batteries?
  3. What is Microsoft wrote it? by quadelirus · · Score: 5, Interesting

    One crash in ten years? Why don't the NASA guys write consumer operating systems?

    1. Re:What is Microsoft wrote it? by edremy · · Score: 5, Insightful
      Actually, they buy their OS's off the shelf. (VxWorks for the rovers, for example)

      That said, you could get software written to this level of perfection if you wanted. It's easy- follow the space shuttle's team's example. You have a stable team of mature developers who work reasonable hours. You test the hell out of the software to the point a single bug in a test is reason to redo the software. You run the software on four identical computers and make sure they all agree.

      Then you hire another entire team to write code that does the same thing, but otherwise has no contact with the first team. That software runs on a fifth computer that takes over if something happens to the other four.

      Willing to pay for that?

      --
      "Seven Deadly Sins? I thought it was a to-do list!"
  4. "Safe" mode? by Bazman · · Score: 5, Funny

    Funny definition of 'safe mode'. I'd get the main antenna pointing at the earth, the battery radiator pointing away from the sun, and the computer going 'what do I do know, smarty earthlings?' and waiting for a command.

    Maybe NASA's 'safe mode' just put 'safe mode' in the corners of all the returned images and did them in 8-bit colour...

  5. Re:Is this a sign? by benevixit · · Score: 5, Insightful

    In all fairness, writing code for a spacecraft is a lot harder than most of our Earthbound coding projects. These are custom-built machines running one-of-a-kind hardware; one can simulate components independently but it's very difficult to figure out how the hardware is going to behave up there in the vacuum. For example, consider the one function of maintaining orientation. Most spacecraft use telescopes that look for star reference points. They look for particular star configurations and use microthrusters or gyroscopes to adjust their orientation. Imagine what it would take to simulate this: a zero-gravity vacuum with a realistic star-field at focus=infinity. Any laboratory mock up is going to cost a lot more than launching a new spacecraft. And that's just one subsystem. Software upgrades at NASA go through a really rigorous quality control regimen, often requiring programmers to justify _individual_lines_ of their code to a review committee. Even then they usually won't patch noncritical bugs until the primary mission is completed. I think your point is a good one. And the key lesson is not that NASA QA sucks, it's that programming for spacecraft is _tough_. I know they are constantly investigating new ways (like more standardization, code re-use, and formal verification procedures) of improving software reliability.

  6. Re:YACCS -Yet Another Computer Corkup in Space by Fishbulb · · Score: 5, Informative

    The F-16 didn't "bounce off the equator". Before it ever flew, in simulation the computer flipped the plane over when it crossed the equator due to a bug that incorrectly handled southern lattitudes. Additionally, since the computer "flip" happened instantaneously, and the f-16 can roll at much higher G forces than the pilot can take, the flip would have killed the pilot (and the F-16 would have happily continued on its way).

    http://portal.acm.org/ft_gateway.cfm?id=163293&typ e=pdf&coll=GUIDE&dl=GUIDE&CFID=11154656&CFTOKEN=19 136062