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Spacecraft Crashes Into Satellite

Juha-Matti Laurio writes "A robotic NASA spacecraft designed to rendezvous with an orbiting satellite instead crashed into its target. Unbeknownst to engineers at the time, DART's main sensor mistakenly believed it was flying away from the satellite when it was actually moving 5 feet per second toward it, investigators found."

12 of 343 comments (clear)

  1. Ah. by toQDuj · · Score: 5, Funny

    So that's where the minus sign should have gone, I knew I dropped it somewhere!

    and an Obligatory Pratchett Quote:

    Hex's pen was scratching across the paper.
    Ponder glanced at the figures.
    ` ..., these figures can't be right!`
    Ridcully grinned again. `You mean either the whole world has gone wrong or your machine is wrong?`
    `Yes!`
    `Then I'd imagine the answer is pretty easy, wouldn't you?` said Ridcully.
    `Yes, it certainly is. Hex gets thoroughly tested every day` said Ponder Stibbons
    `Good point, that man,` Said Ridcully.

    B.

    --
    Every experiment which ends in a big bang is a good experiment.
  2. Question answered! by LackThereof · · Score: 5, Funny

    The $110 million DART mission was meant to test whether robots can perform some of the tasks astronauts currently must do.

    Well, we answered that question. Mission accomplished!

    --
    Legalize recreational marijuana. Seriously.
  3. That's no crash... by calexontheroad66 · · Score: 5, Funny

    it's a successfull hit, now let's build that missile defense system.

  4. Oddly familiar by Brushen · · Score: 5, Interesting
    Where have I heard that before?

    From Challenger:

    "Engineers at Morton Thiokol (manufacturer of the solid rocket boosters) knew that the temperatures were outside of the design range of the O-rings. They strongly objected to the launch, but were overruled by senior Thiokol management."

    From Columbia:

    "In a risk-management scenario similar to the Challenger disaster, NASA management failed to recognize the relevance of engineering concerns for safety. Two examples of this were failure to honor engineer requests for imaging to inspect possible damage, and failure to respond to engineer requests about status of astronaut inspection of the left wing."

    From DART:

    "Investigators also raised issues with the mission's management style, saying that lack of training and experience caused the DART design team to shun expert advice. They also found that internal checks and balances were inadequate in uncovering the mission's shortcomings."

  5. Kennedy Space Center DART? by dotslashdot · · Score: 5, Funny

    In a subsequent news conference, DART claimed it did not remember hitting on the target after being spaced out on AMBIEN, a method it used to help it sleep(500s) before its launch from Kennedy Space Center. DART claimed that it got several bytes to eat before drinking a cup of Java and collecting its garbage. Upon introspection DART agreed that, despite its name, hitting on the target showed little Class despite the size of its Package.

  6. In a related story... by dummyname12 · · Score: 5, Funny

    ...NASA has finally set aside a portion of its budget for the hiring of a trombone player to lighten the mood after each disasterous miscalculation with a well-timed "waaah WAAAAAAAAH."

  7. Where's that ruler? by Whiteox · · Score: 5, Funny

    Are you sure? Is that 5 feet per second or 5 metres per second?

    --
    Don't be apathetic. Procrastinate!
  8. NASA: Get rid of design by management by Morgaine · · Score: 5, Interesting

    As long as scientists and engineers are cogs in an organizational structure in which management tells them what to do, they will often produce crap, no matter how many PhDs there are in their midst. This is the case even when those managers were once brilliant technical engineers and scientists, because perceptions and priorities change when you switch into a management role.

    This little episode was just another in a long line of screwups, and it won't be the last under current organizational models. Doing technical things can't be done properly unless insightful scientists and engineers are free of constraints on their insight, allowed to bypass the directional controls that management so loves, uninhibited from pointing our core problems in fear of their careers, and totally unshackled from the demands of time management.

    Yes, I know that most managers would call this "anarchy", but therein lies the problem: by eliminating that alleged anarchy, you are also sacrificing the best that people can offer, just to make your life easier. Well, perhaps it's stating the blindingly obvious, but making management's life easy is not central to exploring the stars.

    NASA's problem is the same one that permeates all technical industries, but in NASA's case the mishaps are just very public. I don't expect anything to change, but there is no doubting what the general problem is.

    --
    "The question of whether machines can think is no more interesting than [] whether submarines can swim" - Dijkstra
  9. Top Down Design? by Ohreally_factor · · Score: 5, Insightful
    One wonders if this failure is due to a design philosophy similar to the top down design that has doomed the shuttle.

    From the Feynman report:

    The usual way that such engines are designed (for military or civilian aircraft) may be called the component system, or bottom-up design. First it is necessary to thoroughly understand the properties and limitations of the materials to be used (for turbine blades, for example), and tests are begun in experimental rigs to determine those. With this knowledge larger component parts (such as bearings) are designed and tested individually. As deficiencies and design errors are noted they are corrected and verified with further testing. Since one tests only parts at a time these tests and modifications are not overly expensive. Finally one works up to the final design of the entire engine, to the necessary specifications. There is a good chance, by this time that the engine will generally succeed, or that any failures are easily isolated and analyzed because the failure modes, limitations of materials, etc., are so well understood. There is a very good chance that the modifications to the engine to get around the final difficulties are not very hard to make, for most of the serious problems have already been discovered and dealt with in the earlier, less expensive, stages of the process.

    The Space Shuttle Main Engine was handled in a different manner, top down, we might say. The engine was designed and put together all at once with relatively little detailed preliminary study of the material and components. Then when troubles are found in the bearings, turbine blades, coolant pipes, etc., it is more expensive and difficult to discover the causes and make changes. For example, cracks have been found in the turbine blades of the high pressure oxygen turbopump. Are they caused by flaws in the material, the effect of the oxygen atmosphere on the properties of the material, the thermal stresses of startup or shutdown, the vibration and stresses of steady running, or mainly at some resonance at certain speeds, etc.? How long can we run from crack initiation to crack failure, and how does this depend on power level? Using the completed engine as a test bed to resolve such questions is extremely expensive. One does not wish to lose an entire engine in order to find out where and how failure occurs. Yet, an accurate knowledge of this information is essential to acquire a confidence in the engine reliability in use. Without detailed understanding, confidence can not be attained.

    A further disadvantage of the top-down method is that, if an understanding of a fault is obtained, a simple fix, such as a new shape for the turbine housing, may be impossible to implement without a redesign of the entire engine.
    --
    It's not offtopic, dumbass. It's orthogonal.
  10. More info... by jginspace · · Score: 5, Interesting

    This all happened on April 15 2005. A better write-up here: http://www.space.com/news/060516_dart_mishap_updat e.html. And here's the Wikipedia entry: http://en.wikipedia.org/wiki/DART_(spacecraft)

    The satellite it crashed into was defunct. From Wikipedia: "The goal was to develop and demonstrate an automated navigation and rendezvous capability in a NASA spacecraft. Currently, only the Russian Space Agency and JAXA have autonomous space craft navigation.".

    Interesting snippet: "NASA has said the official 70-page report will not be publicly released because it contains sensitive material protected by International Traffic in Arms Regulations (ITAR)".

    This was planned as a "high-risk*, low-budget" mission and I'm sure they learned a lot. (* I suppose high-risk in terms of likelihood of meeting up with the target, not of collateral damage.)

  11. Re:Disband NASA by Ohreally_factor · · Score: 5, Insightful

    Unfortunately, the faulty design was due to the screw ups of a private contractor, so there goes your "private sector" argument.

    --
    It's not offtopic, dumbass. It's orthogonal.
  12. Re:Disband NASA by xoyoyo · · Score: 5, Insightful

    Snore. And out come the free enterprise loonies. The only trouble with your argument is that free enterprise is already perfectly able to indulge in space exploration and, well, hasn't. You can rent time on a launch pad, you can rent space in a rocket. There are many excellent engineering companies who can build more or less any satellite or other space craft you want. But there's no return on doing anything more ambitious than communications satellite. What exactly is the private sector going to do with a Mars probe, say? Sell ad hoardings on the side? (Didn't Beagle II do this?) It's better to regard what NASA and ESA do as a public infrastructure project rather than as competition for private enterprise. The work NASA is doing (mostly competently) is more like building the channel tunnel than a profit-based business. We tried building the tunnel through the private sector, but Eurotunnel has been bailed out by the giovernment and the banks so many times that it's actually ended up costing us far more than it would have done if we'd done it the old fashioned way, even assuming the usual obscene project over-run costs of a public project.