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Communications Mars NASA Power Space

Mars Opportunity Rover Is In Danger of Dying From a Dust Storm (engadget.com) 105

According to NASA, the Mars Opportunity rover is currently trying to survive an intensifying dust storm on the red planet. "The storm's atmospheric opacity -- the veil of dust blowing around, which can blot out sunlight -- is now much worse than a 2007 storm that Opportunity weathered," reports NASA. "The previous storm had an opacity level, or tau, somewhere above 5.5; this new storm had an estimated tau of 10.8 as of Sunday morning." Engadget reports: 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.

Mars Opportunity Rover Is In Danger of Dying From a Dust Storm

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  • by Anonymous Coward on Tuesday June 12, 2018 @03:29AM (#56770336)

    "The brave little rover": https://xkcd.com/695/

  • by bjwest ( 14070 ) on Tuesday June 12, 2018 @03:50AM (#56770388)

    I wonder how long it could last in standby if someone hadn't been foolish enough to force it to waste power phoning home just to say "I'm still here." That single transmission could possibly be what killed it.

    I'd also like to note that if Opportunity wasn't designed to power down safely (or recover to a working state if someone were foolish enough to not have it power down before completely running out of power) recharge the batteries when there's enough sunlight, then have Opportunity restart, someone needs to loose their engineering degree.

    • by Anonymous Coward on Tuesday June 12, 2018 @04:02AM (#56770404)

      The more pressing problem isn't that it can't reboot, it's that it won't be able to clean its panels after the storm, and that's assuming it can even do that. Not to mention the drop in efficiency from getting the panels scarred up by abrasive dust.

      Godspeed little rover, keep up the fight!

      • I'm sure one of the dust devils will come along and clean the panels.

        • I'm sure one of the dust devils will come along and clean the panels.

          This location, on the rim of Endeavour crater, has been pretty windy. So if the rover calls home after the dust storm, there's a pretty good chance that the winds will clean the panels.

      • by Anonymous Coward

        This isn't the first time we've heard that it won't be able to clean it's solar panels after the dust storm.

        What happen all the previous times was that the storm blew the dust away from the solar panels, so they ended up cleaner after the storm.

      • by robbak ( 775424 ) on Tuesday June 12, 2018 @07:32AM (#56770886) Homepage

        Opportunity and Spirit are not fitted with any mechanism to clear their solar panels. Originally, it was assumed that dust on the panels would be what would end the mission. But winds and whirlwinds were found on the planet, these occasionally blew dust from the panels, and the mission was extended.

        The pressing problem is that there won't be enough energy to keep the heaters running, the electronics will cool down to -50C, and either the heaters won't turn back on when the sun returns, or, if they do, the electronics won't work when they defrost.

        • The pressing problem is that there won't be enough energy to keep the heaters running, the electronics will cool down to -50C, and either the heaters won't turn back on when the sun returns, or, if they do, the electronics won't work when they defrost.

          IIRC, the temperature concern isn't just about the electronics - it's also the cameras. The glass in the lenses has a lower coefficient of expansion than the metal rings they're mounted in. This means the metal shrinks faster, and may crack the lenses even a

          • That's the first time I've heard that concern, and I speak to past and present rover drivers on a routine basis. They've never mentioned it. They're not particularly worried about the absolute temperatures, because the presence of all that atmospheric dust prevents the ground from seeing outer space and so the temperatures dno't get absolutely low. What they're concerned about is that the power available is unable to keep the liquid electrolyte in the batterieswarm, and the batteries will either develop cop
            • That's the first time I've heard that concern

              It's discussed in Roving Mars by Stephen Squyres. (You might have heard of him - he's the PI for the MER program.)

              They're not particularly worried about the absolute temperatures, because the presence of all that atmospheric dust prevents the ground from seeing outer space and so the temperatures dno't get absolutely low.

              They're absolutely worried about absolute temperatures - because those temps affect the current draw of the heaters.

      • by careysub ( 976506 ) on Tuesday June 12, 2018 @10:11AM (#56771576)

        At the moment the problem is not how much dust will be on the solar panels after the storm. It is that it will lose all power during the storm, the heaters will stop working, and will then be unable to reactivate afterward.

        The story reports an optical depth of the dust storm of tau=10.8. This is astoundingly dark. The transmittance of light through the atmosphere is 1/e^tau so that only 1/50,000 (0.002%) of the sunlight is getting through! It is effectively perpetual night there right now. This is probably darker than even the heaviest storm clouds on Earth (which only go up to blocking 1/20,000 of the sun light). Thus far the storm has cut off power for six days.

        Although the storm also moderates temperature, since it prevents radiation cooling at night, it also means that the day time high temperatures are not reached either, so that the heaters have to be cranked up constantly (though not to the level of coldest night chill), with no power replacing what is being drained from the batteries.

        It the batteries drain to the level that they can no longer supply the heaters then whether there is dust on the panels after the storm ends will be moot. Opportunity will be dead.

        • ...The story reports an optical depth of the dust storm of tau=10.8. This is astoundingly dark. The transmittance of light through the atmosphere is 1/e^tau so that only 1/50,000 (0.002%) of the sunlight is getting through! It is effectively perpetual night there right now....

          Note that the e^1/tau factor is for direct beam. What this means is that almost all of the light that gets through to the surface is scattered light.

          The tau for a rainy day for earth is very high too. It doesn't mean that the surface is completely dark, it just means that the light that does get through has scattered many times-- you can't see the disk of the sun, but some light does reach the surface.

          10.8 is a record for the highest tau measured from the surface of Mars, though.

        • This is astoundingly dark. The transmittance of light through the atmosphere is 1/e^tau so that only 1/50,000 (0.002%) of the sunlight is getting through!

          The analogy I've been using is of being under a volcanic ash cloud. Literally turning day into night.

    • by Anonymous Coward on Tuesday June 12, 2018 @04:03AM (#56770408)

      It needs battery to keep the internal components at safe temperature levels. It is not about calling home; it is about not freezing.

    • by dgatwood ( 11270 )

      I'd also like to note that if Opportunity wasn't designed to power down safely (or recover to a working state if someone were foolish enough to not have it power down before completely running out of power) recharge the batteries when there's enough sunlight, then have Opportunity restart, someone needs to loose their engineering degree.

      The funny thing is going to be when that storm clears the panels on Spirit enough that it starts phoning home again. :-)

      • Unlikely - the electrolyte in the batteries is almost certainly trashed. Even if the panels produce decent power, without the battery the re-boot process will draw more current than the panels can produce.
    • I wonder how long it could last in standby if someone hadn't been foolish enough to force it to waste power phoning home just to say "I'm still here." That single transmission could possibly be what killed it.

      Um, no.

    • by Anonymous Coward on Tuesday June 12, 2018 @06:33AM (#56770748)

      ...someone needs to loose their engineering degree.

      Someone needs to remember this hardware was originally expected to last 90 days. It's been running for over fourteen fucking years.

      This would probably be one of those times where you should STFU about failures in engineering and design, as the statistics tend to speak for themselves.

      • by GuB-42 ( 2483988 ) on Tuesday June 12, 2018 @08:53AM (#56771170)

        That's 14 earth years, not 14 fucking years.
        That being said, I didn't know that fucking was a planet, we should let more people know, it would really help build interest in space exploration.

      • by psycho12345 ( 1134609 ) on Tuesday June 12, 2018 @08:58AM (#56771190)

        On one hand, I think those engineers need a discussion about underestimating capabilities.

        On the other, I think they need to be given god damm medals for making a project beat its lifespan estimates, not by 10%, not by 100%, not by 1000%, but by 5500%.

      • by lordlod ( 458156 )

        Someone needs to remember this hardware was originally expected to last 90 days. It's been running for over fourteen fucking years.

        This would probably be one of those times where you should STFU about failures in engineering and design, as the statistics tend to speak for themselves.

        As a mass-production engineer I would be asking serious questions about the design process and quality controls.

        Having a product last for over 56x longer than its designed and projected lifespan suggests that there is some serious over engineering involved. Are all those solar panels really needed? What if we added some lightening holes to the neck, the solid piece of aluminum seems like overkill and the weight savings will help lower distribution costs.

        Honestly though, how can anyone pass judgment on t

        • Re: (Score:2, Insightful)

          by Anonymous Coward

          The Internet: passing judgement on others without all the facts is kind of our thing

        • by DRJlaw ( 946416 )

          As a mass-production engineer I would be asking serious questions about the design process and quality controls.

          But the charges for return shipping, or sending out a field tech, would be a real bitch.

          The acceptable risk of failure was a bit lower for this hardware. You wouldn't want to be that guy [space.com].

        • You must work for a smartphone manufacturer. Please quit your job and let me decide when to retire my electronics.

        • Of course there is some serious over engineering involved. The design process and quality controls could likely be summed up as "It just has to work",regardless of the mission's expected duration. There is just too much at stake to even care about minimizing materials beyond the defined mission requirements.

          90 days is likely to be the warrantee period for a cheap motherboard. If you think getting an RMA for one of those is a pain, try getting an RMA for a product delivered to MARS.

      • by King_TJ ( 85913 ) on Tuesday June 12, 2018 @09:53AM (#56771470) Journal

        Seriously, you have to take those claims of "designed for 90 days of operation" with some big grains of salt.... There's no way they'd spend all the money, time and energy on R&D to get something like this put on Mars, when they REALLY only expected it would be used for a few months.

        That might be the length of time they NEEDED to complete the original planned research project, so in a worst-case scenario, NASA doesn't have to say they failed. But I'm quite certain this thing was engineered with the hopes it would run for years and years -- as it has done.

        • Seriously, you have to take those claims of "designed for 90 days of operation" with some big grains of salt....

          Good point. I didn't see the project requirements. My guess is the actual requirement was something like "99% chance of operating for at least 90 days." It wasn't "10% chance of operating 90 days." That's a pretty big difference. I might be able to build the latter. I have no chance on the former.

        • There's no way they'd spend all the money, time and energy on R&D to get something like this put on Mars, when they REALLY only expected it would be used for a few months.

          Why not? The first month of operation was likely the most insightful and it did most everything it was going to do and flexed all of it's scientific equipment. It got pictures, dug a trench, analyzed the air, and did spectrometry. It also traveled to a location with hematite, which geologists were eager to study. That's all in month 1.

          Given a set of tools, there's only so much science you can do. Rovers can move around and use the same tools and more locations, which is awesome, but eventually there w

    • If you think they didn't think of that, then *you* should lose yours.

    • by Joce640k ( 829181 ) on Tuesday June 12, 2018 @09:53AM (#56771474) Homepage

      someone needs to loose their engineering degree.

      I don't know about that but somebody definitely needs to learn to spell "lose".

      It's only four letters, FFS.

  • Tau (Score:5, Informative)

    by Anonymous Coward on Tuesday June 12, 2018 @04:09AM (#56770416)

    Since this article doesn't explain it, an optical depth tau value of 10.8 means approximately 0.002% of the sunlight is reaching the rover, compared to 0.4% for the last storm. It's really, really dark out there.

  • they should build it to look like a GIANT beetle, and build the solar panels like the wings that can fold out when the conditions are good and when not so good fold in and collapse flat with a hard weather-proof outer shell that covers and protects them (like some beetles that can fly)
    • by Anonymous Coward

      Or maybe they should build the next rover so it doesn't need solar panels. Maybe use a nuclear power source like an RTG. How cool would that be? They could name it Curiosity.

    • they should build it to look like a GIANT beetle, and build the solar panels like the wings that can fold out when the conditions are good and when not so good fold in and collapse flat with a hard weather-proof outer shell that covers and protects them (like some beetles that can fly)

      That is not a bad description of the Soviet Lunakhod rover design, which enclosed the array at night.. Although most people say that they look more like a giant bathtub than a beetle.

  • by cascadingstylesheet ( 140919 ) on Tuesday June 12, 2018 @08:02AM (#56770958)

    "The storm's atmospheric opacity -- the veil of dust blowing around, which can blot out sunlight -- is now much worse than a 2007 storm that Opportunity weathered," reports NASA.

    The storms are getting worse ... what do you Martian "deniers" say now, eh???

  • by The Cynical Critic ( 1294574 ) on Tuesday June 12, 2018 @08:47AM (#56771150)
    Considering how the two solar powered rovers (Spirit and Opportunity) that touched down in January 2004 were originally only expected to survive for a few months only to have one finally go out in March of 2010 and the second finally in real peril of going out in June of 2018 it shouldn't be too much of a loss for the second one to finally go out. Both of them spectacularly outperformed what was expected of them and it's probably time for the last of them to quit it with the victory laps. Not that Curiosity, their bigger nuclear-powered older bother, isn't doing well for itself either. It touched down in August 2012 and it's too still going despite an originally planned two year mission length. I'm interested to see if it'll last even longer or if the decay of it's Pu238-dioxide power source will be what keeps it from extending it's mission beyond the original goal by as much as Opportunity has.
    • by necro81 ( 917438 ) on Tuesday June 12, 2018 @09:28AM (#56771348) Journal

      Not that Curiosity, their bigger nuclear-powered older bother, isn't doing well for itself either. It touched down in August 2012 and it's too still going despite an originally planned two year mission length. I'm interested to see if it'll last even longer or if the decay of it's Pu238-dioxide power source will be what keeps it from extending it's mission beyond the original goal by as much as Opportunity has.

      The decay of Pu-238 will not be what limits the Curiosity mission. It has a half-life of 87.7 years. The RTG that uses that decay to produce electricity (and, perhaps more importantly at the moment, heat to keep the electronics happy) decays more quickly than that. But the Voyager probes still have enough electricity to communicate with earth forty years after launch.

      The limiting factor for Curiosity will probably be its moving parts. Specifically, its drive motors and wheels. The wheels have taken quite a beating [google.com], and may eventually be so damaged that they can no longer provide adequate traction. The JPL guys are really clever, and can probably drive Curiosity even with the complete loss of one wheel.

      But even if Curiosity stopped moving tomorrow, it would almost certainly still be useful for stationary science. It can continue to gather weather data (including measuring atmospheric methane, which hit the news recently), take pictures, shoot lasers, and sample rocks, probably for years. One of the Viking landers lasted 6 years on the surface, and that mission ended only after a bad software update [wikipedia.org].

      • by The Cynical Critic ( 1294574 ) on Tuesday June 12, 2018 @10:16AM (#56771604)
        The problem with the RTG isn't that it's going to decay completely, it's that being about the size and weight of car it's packed with way more power hungry systems the RTG may not be able to power anymore once it's been going around for the better part of a decade. Sure, it's got batteries to cover for peaks, but those have been needed from the start and will probably decay faster than the RTG and a battery failure was after all what killed Viking 2 despite also being RTG powered.

        Solar panels definitely also decay over time, but those on the Mars Pathfinder mission saw a long term degradation of only about 0.15% per (earth) year. Their decay doesn't also require more energy to be used for heating due to less waste heat being produced.

        I'm probably worrying too much and the thing that kills Curiosity probably is the environment with the way the soil is rich in really corrosive substances like perchlorate.
        • by tlhIngan ( 30335 )

          , it's that being about the size and weight of car it's packed with way more power hungry systems the RTG may not be able to power anymore once it's been going around for the better part of a decade

          And the goal is to simply not power everything at once. There's a minimum amount of power it needs to run the basics, yes, and that minimum is probably served by the RTG for decades

          All the power hungry science packages can simply be turned off when they're not needed or used, conserving available power as it deca

      • The decay of Pu-238 will not be what limits the Curiosity mission. It has a half-life of 87.7 years. The RTG that uses that decay to produce electricity (and, perhaps more importantly at the moment, heat to keep the electronics happy) decays more quickly than that. But the Voyager probes still have enough electricity to communicate with earth forty years after launch.

        Not true. Loss of power generating capacity is already limiting what the Voyager probes can accomplish - and they're only 41 years old. Whil

        • by necro81 ( 917438 )
          I agree that the decay of the RTG's capacity is limiting the voyager probe. But, it has been 40 years, and well past even the "extended" mission out to Neptune. My broader point with Curiosity was this: what is more likely to give out and end the mission, the RTG or some other component? My bet is that it won't be the RTG; something else will fail first.
    • ... originally only expected to survive for a few months ...

      I think you're abusing the word "expected".

      There was a high-likelihood failure mode (involving dust accumulation) which was baked into the mission parameters, whose budgetary concerns centered around achieving a minimum sufficient return on investment (the worst outcome of all in space exploration is no learning).

      But if you'd asked anyone involved with a clue, they'd have said that the uncertainty around the dust accumulation model was high, and th

  • If I remember correctly, one such sandstorm also _cleaned_ the solar panels in the past.

  • There was a book or movie about this. We need to ship Opportunity some potatoes and duct tape, something like that.

  • by Anonymous Coward

    If NASA was like really smart,they could have equipped the rover with flashlights that would shine on the solar panels when the sun is obscured by a dust storm. Problem solved! But noooo, NASA is of course full of liberal elitists who just use equations to explain why something cannot get done!

  • 15 YEARS into its 90 DAY mission.

    IthinkitcanIthinkitcanIthinkitcan.

Research is what I'm doing when I don't know what I'm doing. -- Wernher von Braun

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