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posted by janrinok on Tuesday June 12, @10:42PM   Printer-friendly
from the we're-rootin'-for-you dept.

The Mars Opportunity rover is caught in a dust storm, and the craft is hunkered down doing its best to survive the intensifying weather. The storm was first detected on Friday June 1st by the Mars Reconnaissance Orbiter, at which point the rover's team was notified because of the weather event's proximity to Opportunity. The rover uses solar panels, so a dust storm could have an extremely negative impact on Opportunity's power levels and its batteries.

By Wednesday June 6th, Opportunity was in minimal operations mode because of sharply decreasing power levels. The brave little rover is continuing to weather the storm; it sent a transmission back to Earth Sunday morning, which is a good sign. It means there's still enough charge left in the batteries to communicate with home, despite the fact that the storm is continuing to worsen.

[...] The main concern here isn't the dust storm itself. It's the need to keep the rover's heaters operational while maintaining a minimal power level in the batteries. This isn't the first storm that Opportunity has weathered, but it is the worst. According to NASA, the weather event the rover faced in 2007 had an opacity level around 5.5. The estimate for this current storm is somewhere around 10.8.

Opportunity is a hardy little rover, though, and it has continually defied our expectations over the last 15 years. The rover was only designed to last for a 90-day mission, and yet it's still going. Here's hoping that Oppy will continue its trek across the Martian surface for many, many days to come.


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  • (Score: 2) by bob_super on Tuesday June 12, @11:07PM (5 children)

    by bob_super (1357) on Tuesday June 12, @11:07PM (#692134)

    Opportunity sensors reports smells not unlike hunkering down inside a Tauntaun.

    Last time Mars threw one of those at it, that actually cleaned up the panels, making it stronger.
    Next step is super-sayan rover mode. Cue the XKCD about Opportunity becoming sentient and controlling half of Mars by the time we get there.

    • (Score: 2) by Thexalon on Tuesday June 12, @11:14PM

      by Thexalon (636) on Tuesday June 12, @11:14PM (#692141) Homepage

      Opportunity sensors reports smells not unlike hunkering down inside a Tauntaun.

      Last time Mars threw one of those at it, that actually cleaned up the panels, making it stronger.

      Mars has tauntauns? That's really big news!

      --
      A foolish consistency is the hobgoblin of bad gravy.
    • (Score: 2) by richtopia on Wednesday June 13, @04:25PM (2 children)

      by richtopia (3160) Subscriber Badge on Wednesday June 13, @04:25PM (#692391) Homepage Journal

      The main concern here isn't the dust storm itself. It's the need to keep the rover's heaters operational while maintaining a minimal power level in the batteries. This isn't the first storm that Opportunity has weathered, but it is the worst. According to NASA, the weather event the rover faced in 2007 had an opacity level around 5.5. The estimate for this current storm is somewhere around 10.8.

      It is not so much surviving the storm, but sustaining minimum power during the storm. An update from the article:

      Update (June 13th at 10:00 AM): NASA released more information about Opportunity last night, and things don't look good. The rover's team tried to contact Opportunity yesterday and didn't receive a response. They are assuming this means that the rover's batteries are now critically low, and it's currently in low power fault mode. This means that all subsystems except the mission clock have been shut down, and the computer will automatically reawaken to check power levels.

      • (Score: 2) by bob_super on Wednesday June 13, @05:02PM (1 child)

        by bob_super (1357) on Wednesday June 13, @05:02PM (#692406)

        > sustaining minimum power during the storm

        "keep the rover's heaters operational", because under 40 degrees, even mil/space chips may not operate. Hence the "keep warm" Tauntaun reference.

        Yuck, I don't like this update. Discard a car after 15 years, sure, but after 15 years of defying the odds, you kind of have to root for that toy.

        • (Score: 2) by kazzie on Wednesday June 13, @07:55PM

          by kazzie (5309) Subscriber Badge on Wednesday June 13, @07:55PM (#692503)

          That comment's got me thinking: Opportunity has been as on Mars for as long as my 14-year-old car has been out of the factory.

    • (Score: 2) by Runaway1956 on Thursday June 14, @02:15AM

      by Runaway1956 (2926) Subscriber Badge on Thursday June 14, @02:15AM (#692654) Journal

      I just checked my bottle of Martian Dust Storms. There's a warning, "Not to be taken internally."

      --
      #eatyourliver #WalkAway #CTRLLeft #MUH_FREEZE_PEACH!!!111one
  • (Score: 2) by bzipitidoo on Tuesday June 12, @11:11PM (15 children)

    by bzipitidoo (4388) on Tuesday June 12, @11:11PM (#692138) Journal

    90 days was an extremely conservative and overly pessimistic prediction of the longevity of these rovers. I sort of understand why they made such low predictions-- trying to manage expectations, keep the predicted budget low so Congress wouldn't cancel the program, that sort of thing. It's a game NASA has played for years. For instance, in the 1980s, Voyager 2's mission had to be extended to view Uranus and Neptune. Congress is surely on to them by now. Makes the game pretty much pointless, but both groups still play it.

    Wonder what they thought the likely lifetime of these rovers really was? 3 years?

    • (Score: 3, Insightful) by MichaelDavidCrawford on Tuesday June 12, @11:34PM

      Congress' memory doesn't include much beyond the last election.

      While there are some career congresscritters a great many of them only "serve" one or two terms.

      --
      Google Search for Fuck MDC [google.com]. I get 470,000 hits; and you?
    • (Score: 3, Interesting) by bob_super on Wednesday June 13, @12:02AM

      by bob_super (1357) on Wednesday June 13, @12:02AM (#692154)

      - Surviving the landing
      - Deploying the comms antennas correctly
      - Not getting stuck in the sand
      - Not getting too much sand on the panels
      - Batteries not dying

      First three successes means you get some science done, as long as the last two keep happening. Forecast for batteries has to be conservative given the insane requirements. The sand accumulation was supposed to be the progressive killer, and NASA/JPL have been very happy to fall on the low end of those estimates. I don't think anyone expected to go past a winter or with great luck two, so starting the ball at 90 days was a way to be better than expected.

    • (Score: 1, Informative) by Anonymous Coward on Wednesday June 13, @12:05AM (5 children)

      by Anonymous Coward on Wednesday June 13, @12:05AM (#692156)

      There is a lot of engineering math that goes into longevity calculations. By a lot, I mean hundreds of thousands of lines of math that is derived by use of symbolic math applications like matlab or mathematica.

      In order to meet the mission requirement of 90 days or whatever with a 95% confidence level, you need multiple levels of redundancy on parts with a mtbf of thousands of hours.

      tl;dr: In order to guarantee that there is a 99% chance of making it to 90 days, you have to build in multiple levels of redundancy using parts with a 99.99% chance of lasting ten years. This is why your toaster breaks 3 days after the one year warranty. See reliability engineering (https://en.wikipedia.org/wiki/Reliability_engineering).

      • (Score: 1) by khallow on Wednesday June 13, @05:28AM (4 children)

        by khallow (3766) Subscriber Badge on Wednesday June 13, @05:28AM (#692235) Journal
        Or pull a number out of your ass. It's not like anyone in Congress cared. Just make sure those funding checks go to the right people.

        In order to guarantee that there is a 99% chance of making it to 90 days, you have to build in multiple levels of redundancy using parts with a 99.99% chance of lasting ten years.

        Or you can fly a bunch of probes and see what makes them last longer. Time on the ground trumps wads of money spent on untested (and thus, unreliable) reliability testing. Let us note in the example above, that you could chain roughly 400 such parts, every one of them a single point of failure, to yield the desired failure rate. I don't think you need that many components on a Mars rover, much less have them to that reliability and redundancy. But it's not my stage to run.

        • (Score: 2) by bob_super on Wednesday June 13, @04:37PM (3 children)

          by bob_super (1357) on Wednesday June 13, @04:37PM (#692394)

          > Time on the ground trumps wads of money spent on untested (and thus, unreliable) reliability testing.
          > Let us note in the example above, that you could chain roughly 400 such parts, every one of them a single point of failure,
          > to yield the desired failure rate. I don't think you need that many components on a Mars rover,
          > much less have them to that reliability and redundancy.

          You're somewhere between Dunning-Kruger and amazingly wrong.
          "Time on the ground" is a nine-figures line item, so you build lots of redundancies, and do a lot of testing under all possible conditions, during the ten years it takes to build the rover. Reliability testing is pretty good these days, with is how a rover can last 15 years on Mars, or a few years going through Jupiter's and Saturn's radiation belts.

          With lowering launch costs, sending a bunch of microsats could start to make sense, but landing on Mars, and roaming around sandy terrain while sending data all the way back to Earth, is putting a minimum size requirement (even when the experiments don't), which drives the 9-figures trip, which drives the "make it last" redundancies and testing.

          • (Score: 1) by khallow on Thursday June 14, @03:34AM (2 children)

            by khallow (3766) Subscriber Badge on Thursday June 14, @03:34AM (#692678) Journal

            "Time on the ground" is a nine-figures line item

            Getting NASA out drops it to an eight-figures. SpaceX and more mass available for a mission (which greatly reduces the need for extreme, and extremely costly, mass optimization) would drop it to seven. Mass production combined with ISRU probably could then drive it down to five-figures though it's a lot of overhead, if you're not settling the planet. Overpriced reliability testing to ridiculous degrees would be one of the early on casualties.

            You're somewhere between Dunning-Kruger and amazingly wrong.

            Do the math yourself. (0.9999^100) ~ 0.99, meaning that 100 such parts each with its own 0.9999 chance of stopping the mission could be introduced and still have a 99% chance of success over a year's time. Reducing that to 90 days means you can quadruple the number of parts and still maintain the 99% chance of success over the shorter period of time.

            What's really futile about this degree of reliability testing is that you aren't doing it often enough to know whether it works or not. Doing it successfully for twenty projects means that you don't know whether it's successful 99% of the time or 95% of the time (a big difference!).

            • (Score: 2) by bob_super on Thursday June 14, @05:20AM (1 child)

              by bob_super (1357) on Thursday June 14, @05:20AM (#692718)

              That's what Beam Time is for.
              You don't just build one each time. You build a bunch (because the cost is in the design much more than the BOM), and test the heck out of a big sample, before picking one.
              Don't underestimate failure analysis and fault tolerance designs. Some of this stuff is really amazing.

              • (Score: 1) by khallow on Friday June 15, @03:52AM

                by khallow (3766) Subscriber Badge on Friday June 15, @03:52AM (#693322) Journal

                You don't just build one each time. You build a bunch (because the cost is in the design much more than the BOM), and test the heck out of a big sample, before picking one.

                Actually, most of the time they do build just one. The MERs were a little exceptional in that they built two.

    • (Score: 2) by suburbanitemediocrity on Wednesday June 13, @12:12AM (2 children)

      by suburbanitemediocrity (6844) on Wednesday June 13, @12:12AM (#692159)

      It's not a prediction out of nowhere. There is as much engineering, if not more, that goes into reliability as goes into any other part of the system.

      • (Score: 0) by Anonymous Coward on Wednesday June 13, @05:27AM (1 child)

        by Anonymous Coward on Wednesday June 13, @05:27AM (#692234)

        One of the reasons for the 90-day estimate was dust levels on the solar panels. Prior missions suggested they'd have risky amounts of dust after a few months. But, whirlwinds keep cleaning them off. This was unexpected.

        • (Score: 3, Touché) by bob_super on Wednesday June 13, @04:57PM

          by bob_super (1357) on Wednesday June 13, @04:57PM (#692402)

          I've always had the hardest time including whirlwinds in my schedules and estimates. They're such a pain to manage.

    • (Score: 2) by jmorris on Wednesday June 13, @12:56AM

      by jmorris (4844) <{jmorris} {at} {beau.org}> on Wednesday June 13, @12:56AM (#692178)

      It isn't just a scam. It is about setting expectations for everyone. If you declare you are designing for a one year mission people will start asking why there aren't some more science things on it to keep it busy for a year. So then you have to make it bigger, more expensive and probably more prone to fail. Oops. And no matter what, now if it fails in six months you will get declared only partly successful. Better to declare a mission time in line with what you are trying to accomplish and if the thing is still in good condition after you achieve all of that; then reevaluate based on new the information you already have about where you landed, what still works, what systems are questionable, and just how much extra abuse you think the machine is up for.

      All these rovers were intended to do was land, look around and instead of being limited to just examining whatever they happened to fall out of the sky on, be able to see a couple of nearby interesting things to go make closeup examinations of a few of them, poke a hole in a couple, that sort of thing. Even with all this time Opportunity hasn't exactly covered a lot of ground, not even 50 kilos, and not it a straight line. Had they been building them to run a decade they would have built them very differently. Certainly provided a way to keep the solar collectors clear.

    • (Score: 1) by khallow on Wednesday June 13, @05:33AM

      by khallow (3766) Subscriber Badge on Wednesday June 13, @05:33AM (#692238) Journal
      The obvious rebuttal is ISLE - Improving Standards by Lowering Expectations. It's not just a joke, it works in real life as well. There's no reason to promise them the Moon when you're going to Mars instead!
    • (Score: 0) by Anonymous Coward on Wednesday June 13, @07:40AM

      by Anonymous Coward on Wednesday June 13, @07:40AM (#692259)

      Were they predictions? Or were the rovers simply ordered with a 90 day on site replacement warranty?

      The reason everything these days fails on average two days after the warranty expires is that replacing the ones that fail before the warranty expires is cheaper than building things to last.

    • (Score: 2) by krishnoid on Wednesday June 13, @10:11PM

      by krishnoid (1156) on Wednesday June 13, @10:11PM (#692570)

      I wonder if they could parlay this entry in the news cycle into a marketing point for funding for more Mars (or other) probes, as a success story for how NASA gets so much bang for their buck.

  • (Score: -1, Flamebait) by Anonymous Coward on Tuesday June 12, @11:32PM

    by Anonymous Coward on Tuesday June 12, @11:32PM (#692148)

    "Please don't take this the wrong way, but could you buy me three of the smallest butt plugs".

    A prolapsed rectum is no joke. All he can do just now is to sit on a tennis ball.

  • (Score: 4, Insightful) by takyon on Wednesday June 13, @12:46AM

    by takyon (881) Subscriber Badge <takyonNO@SPAMsoylentnews.org> on Wednesday June 13, @12:46AM (#692173) Journal

    Maybe some dust devils can clear things up. Again.

    --
    [SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
  • (Score: 3, Funny) by Entropy on Wednesday June 13, @02:40AM (2 children)

    by Entropy (4228) on Wednesday June 13, @02:40AM (#692196)

    Are clearly caused by global warming. We need to do our part such as switching to soy based foods to limit the beef industry methane production!

    • (Score: 1, Funny) by Anonymous Coward on Wednesday June 13, @05:30AM

      by Anonymous Coward on Wednesday June 13, @05:30AM (#692237)

      Mars Trump has blue skin and green hair.

    • (Score: 2, Funny) by Anonymous Coward on Wednesday June 13, @08:06AM

      by Anonymous Coward on Wednesday June 13, @08:06AM (#692263)

      You haven't been keeping up.

      Climate change is caused by cars. Before: Zero cars on Mars. Now: Three cars on mars. That's an increase of more than several orders of magnitude.

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