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Mars NASA Power Space

Mars Lander Faces Slow Death 212

Posted by Soulskill
from the this-lander-will-self-destruct-in-five-months dept.
Riding with Robots writes "It's the beginning of the end for the Phoenix Mars Lander. As winter approaches in the Martian arctic, NASA says it's in a 'race against time and the elements' in its efforts to prolong the robotic spacecraft's life. Starting today, mission managers will begin to gradually shut the lander's systems down, hoping to conserve dwindling solar power and thereby extend the remaining systems' useful life. 'Originally scheduled to last 90 days, Phoenix has completed a fifth month of exploration in the Martian arctic. As expected, with the Martian northern hemisphere shifting from summer to fall, the lander is generating less power due to shorter days and fewer hours of sunlight reaching its solar panels. At the same time, the spacecraft requires more power to run several survival heaters that allow it to operate even as temperatures decline.'"
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Mars Lander Faces Slow Death

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  • NASA (Score:5, Funny)

    by Sasayaki (1096761) on Wednesday October 29, 2008 @04:19AM (#25552231)

    Honestly, as an Australian, it's great to see NASA in the news for something which can't be summarised as: "It blew up".

    Needs more funding IMHO.

  • Ever since the two loses in 2000, NASA has had amazing success with Mars. We now have a fleet of spacecraft orbiting and on the surface of Mars. But the biggest kudos have to go to an all-around amazing guy, and my favorite professor during my undergrad education, Steve Squyres, who's "90 day" rovers are now toddlers on Mars.
    • Hmmm, I wrote "who's" instead of "whose." Well, there's a reason I wasn't an English major as an undergrad I guess...

      I still remember the day he came into class and told us about the rovers. He had literally just gotten off the plane from JPL, and asked if there were any reporters in the room (for the school paper or otherwise). He then told us that since there wouldn't be a public announcement of the MERs for another month or so, that everything he told us was "off the record." it was so cool to learn that and all the other insider-info.
      • by Ihmhi (1206036)

        Hmmm, I wrote "who's" instead of "whose." Well, there's a reason I wasn't an English major as an undergrad I guess...

        Don't feel so bad about it. It's rather easy to get a degree as an English major. Hell, they have a whole roll of them in the men's lavatory.

        • by elrous0 (869638) *
          Could be worse. They give Ph.D.'s in education away with the sunrise breakfast at Denny's now.
    • by savuporo (658486) on Wednesday October 29, 2008 @04:35AM (#25552301)

      Yes, Mars they are doing. But do you remember when the last lunar soft landing happened ?
      1976, Luna-24, a successful sample return probe sent by USSR.

      There is a likelyhood that the next one to land will be a Google Lunar X-Prize participant ..

      • by meringuoid (568297) on Wednesday October 29, 2008 @05:15AM (#25552499)
        Yes, Mars they are doing. But do you remember when the last lunar soft landing happened ? 1976, Luna-24, a successful sample return probe sent by USSR.

        To be fair here, Luna 24 returned 170.1g of regolith. NASA on the other hand landed six 14.7 tonne probes on the Moon in the late sixties to early seventies. They deployed a total of twelve autonomous intelligent versatile exploration units, traversing a total of 97km of lunar surface, and gathered some 381.7kg of samples and returned them to Earth.

        To follow that spectacular accomplishment with a few petty robot landers seems... pointless.

        • by Cyberax (705495) on Wednesday October 29, 2008 @05:18AM (#25552509)

          But much cheaper.

          • Re: (Score:3, Funny)

            by Ihmhi (1206036)

            Unfortunately, the Russians were unable to allocate gyros and other mechanisms for the golf-swinging arm of the robot in their design, so their funding was heavily slashed.

        • by savuporo (658486) on Wednesday October 29, 2008 @05:35AM (#25552577)

          So you are saying that sending robots to Shackleton crater to search for water ice, or sending prototype plants to test out ISRU technologies like cooking oxygen out of lunar regolith would be rather pointless, just because a bunch of astronauts already made some footprints there ?

          I am not disputing the accomplishments of Apollo, but to say that lunar robots are pointless is naive.

          By the way, looking at the launch calendars, it looks like Indo-Russian joint mission Chandrayaan II might beat GLXP to the lunar surface.

          Its been sad that our closest neighbour has been basically forgotten for so long, and now with Chinese, Indians and Japanese entering the lunar exploration, things are looking up.

          • by mallumax (712655)
            For the record, Chandrayaan I has already been launched and it is on its way to the Moon. Also it is not Indo-Russian mission. It is purely an Indian Mission.
            • by savuporo (658486)

              Yes, everyone paying the slightest attention to space developments knows about Chandrayaan I, and it being an Indian effort.

              I specifically said that Chandrayaan II will be an indo-russian mission, with lander and rover being provided by Roskosmos.

    • by lpontiac (173839)

      I read his book [amazon.com]. Recommended.

    • Re: (Score:2, Funny)

      by kungfugleek (1314949)

      We now have a fleet of spacecraft orbiting and on the surface of Mars...

      Makes me wonder if anyone on Mars has welcomed their new robotic earthling overlords...

    • by elrous0 (869638) *
      Those little rovers are the closest thing to life that sterile rock has ever known.
    • Re: (Score:3, Insightful)

      by wren337 (182018)

      The secret to exceeding expectations is to set them very low. In this case, they built rovers that might last several years, then slapped a "90 day warranty" sticker on them.

  • Why heaters? (Score:5, Interesting)

    by Richard W.M. Jones (591125) <rich.annexia@org> on Wednesday October 29, 2008 @04:32AM (#25552287) Homepage

    So honest question for all you rocket scientists out there: Why are heaters needed? Which parts of the spacecraft (electronics?) need to be above a certain temperature to operate? Is it possible to let the lander "freeze" and then revive it, or if not what components are sensitive to this?

    Rich.

    • Re:Why heaters? (Score:5, Informative)

      by MichaelSmith (789609) on Wednesday October 29, 2008 @04:39AM (#25552327) Homepage Journal

      So honest question for all you rocket scientists out there: Why are heaters needed? Which parts of the spacecraft (electronics?) need to be above a certain temperature to operate? Is it possible to let the lander "freeze" and then revive it, or if not what components are sensitive to this?

      Rich.

      One issue is that solder joints between components can break if they are cooled down too much. Batteries and capacitors can fail if liquids inside them freeze and crystalise. While I think there is a chance that the lander will come back up next summer but the likelyhood of this is pretty slim IMHO.

    • Re:Why heaters? (Score:5, Informative)

      by jm1234567890 (888822) on Wednesday October 29, 2008 @04:41AM (#25552339) Homepage
      From the article

      The heaters serve the purpose of keeping the electronics within tested survivable limits.

    • by danhuby (759002) on Wednesday October 29, 2008 @04:41AM (#25552345) Homepage

      The heaters serve the purpose of keeping the electronics within tested survivable limits.

      IANARS, I just RTFA

    • Re: (Score:2, Interesting)

      by sa1lnr (669048)

      Can't speak for this exactly but a friend of mine has a vapo-chill unit on one of his PC's and he managed to get the temps so low on the cpu that it stopped working.

    • Re:Why heaters? (Score:5, Informative)

      by Lumpy (12016) on Wednesday October 29, 2008 @06:43AM (#25552873) Homepage

      It's the mechanical moving parts as well as the batteries and other delicate systems. Problem is these parts are larger than the rovers that simply use hot radiation pellets of plutonium dioxide to do the heating for them.

      They CAN shut it all down, park the moving parts and let it sit dormant for all winter, but when you shut a system down there is a good chance that when you fire it up in the spring that it will not fire up. Blown dust cakes into an armature hinge point and now it can no longer move.

    • I don't know about Mars rovers, but here on Earth, there radio systems that need to be kept warm, or they drift off frequency. Next spring, it would be hard to wake up the rover if it can't hear the alarm clock ringing.
    • Re: (Score:3, Informative)

      by LWATCDR (28044)

      Batteries are number one.
      Capacitors would be number two.
      Solder joints from uneven contraction.
      We are talking about cold here. I mean a cold that makes Antarctica look warm.
      Too bad they didn't use an RTG. The colder they get the more power they make.

    • Re: (Score:3, Informative)

      The temperature extremes experienced in spacecraft (the Antarctic and Artic here on Earth) are such that considerable thermal expansion and contraction occurs. Because materials have different thermal expansion coefficients, everything is expanding and contracting at different rates, leading to mechanical stress. Such stresses cause hardening of materials - rather than flexing with the stress as when they were new, they break, and there-in lies the problem. (Remember bending wire coat hangers until they bre
  • by dotancohen (1015143) on Wednesday October 29, 2008 @04:32AM (#25552289) Homepage

    ...can we then assume that since something _died_ on Mars that there was once something _living_ on Mars?

  • by apodyopsis (1048476) on Wednesday October 29, 2008 @04:48AM (#25552371)
    here's what I do not understand.

    so no sunlight = no power. the lander dies.

    but in the next season, assuming it has not been buried in dust it will then get power again from the solar array, so what then? surely some basic SW should be functional as the power rises over a certain point. and it does not need a huge amount of power to transmit basic telemetry like temperature, light, perhaps the odd photo in low res broadcast at low power.

    with all the research and development that went into the thing, I do not see why one season should kill it.

    however, I recognize I am not an expert and the people who write the articles presumably are, so what have I missed?

    corrosion in the environment?
    batteries that cannot survive being fully discharged?
    lander cannot run on solar alone?

    anyhow, kudos to NASA for lasting well beyond the tables life span in the first place.
    • by u38cg (607297) <calum@callingthetune.co.uk> on Wednesday October 29, 2008 @05:07AM (#25552453) Homepage
      Metal parts can potentially crack, any components with liquids in them (batteries, capacitors, etc) can freeze and split. Certainly they will be keeping their fingers crossed that it might come back to life next year, but the odds are low.
      • by Dr.M0rph3us (1256296) on Wednesday October 29, 2008 @06:24AM (#25552765)

        What I'd like to see is the development of cold-resistant electronics. Can we use solid capacitors and batteries for that purpose?

        Then the power-draining heaters won't be needed anymore and the power can be routed to more useful instruments (or the probes can be lighter, with lower launch costs).

        • Re: (Score:2, Insightful)

          by vbraga (228124)

          Metal parts, solder joints must also be taken in account.

          I think it's actually possible to build a spacecraft resistant to this temperature. But testing over a wider temperature range and getting it build to this spec would be expensive as hell.

          (I'm not a native English speaker, so, be kind pointing mistakes =))

          • Re: (Score:3, Insightful)

            by Peeteriz (821290)

            But testing over a wider temperature range and getting it build to this spec would be expensive as hell.

            On the other hand, 'expensive as hell' is not that much when compared to the cost of getting a pound of stuff from Earth to Mars - so if it allows us to use the rover twice as long, then it may be cheap enough to do, as sending a ten times more expensive rover would be much cheaper than sending two current rovers, just due to the high cost of transport.

            • On the other hand, 'expensive as hell' is not that much when compared to the cost of getting a pound of stuff from Earth to Mars - so if it allows us to use the rover twice as long

              These rovers were only made to last 90 days. AS far as anyone is concerned, they have ALREADY lasted nearly 20 times longer than they were supposed to last (1760 days versus 90).

              So it would not be unreasonable to assume that maybe just maybe, if there was a choice of paying X for a part that lasts 1 year, or 100X for a part that lasts ten years, they would choose to get the 1 year part.

              To be fair, these things were only supposed to last for 90 days. I do not think, looking back at the original remit of the

          • by Rogerborg (306625)

            But testing over a wider temperature range and getting it build to this spec would be expensive as hell.

            As opposed to launching it, which is cheap as chips?

    • by timmarhy (659436) on Wednesday October 29, 2008 @05:33AM (#25552565)
      see this is why NASA is putting robots on mars and you aren't. try freezing your dick to minus -225 and see if it's still functional next season.

      ok sorry i'm being a little harsh there it's been a long day. solder will crack and oils will freeze and expand busting caps etc. that's why the lander might not make it through the winter.

    • by OriginalArlen (726444) on Wednesday October 29, 2008 @06:01AM (#25552667)
      You've got it. Firstly the batteries will be destroyed by the prolonged cold. The other thing is that the entire site will be cloaked in a couple of meters of CO2 ice over winter; as it accumulates on the solar panels, the weight is expected to physically snap them off.
      • Re: (Score:2, Insightful)

        by CFBMoo1 (157453)

        You've got it. Firstly the batteries will be destroyed by the prolonged cold. The other thing is that the entire site will be cloaked in a couple of meters of CO2 ice over winter; as it accumulates on the solar panels, the weight is expected to physically snap them off.

        It would be neat if they could watch the entire process of this happening. I really wish they could build a probe that could monitor this on the ground.

  • It has a "pyrotechnic initiation unit"? What is that used for? Were they planning some fireworks to celebrate? Do Martians like fireworks? :)

  • Oblig. (Score:5, Funny)

    by cosmocain (1060326) on Wednesday October 29, 2008 @04:49AM (#25552379)
    I, for one, mourn our dead robotic overloads.
  • If only they sent a few baby capsules up there to supply it with the 25,000 btu's of body heat and 120 volts of power per unit.

  • by Anonymous Coward on Wednesday October 29, 2008 @05:46AM (#25552613)

    the native martians will appear and take it into their homes for the winter and nurse it back to health...

  • Nuclear batteries (Score:5, Insightful)

    by joshv (13017) on Wednesday October 29, 2008 @06:38AM (#25552833)

    Why the hell aren't we putting nuclear batteries on these things?

    • Re: (Score:3, Informative)

      by Carbon016 (1129067)
      They [space.com] might [theregister.co.uk] on the successor.
    • Re:Nuclear batteries (Score:4, Informative)

      by Anonymous Coward on Wednesday October 29, 2008 @07:14AM (#25553011)

      The word nuclear scares the public. More specifically I live by the cape, when they launch nuclear powered missions like New Horizons Pluto mission local schools are required to keep children indoor and close their windows. This is a precaution. If the launch vehicle blows up nuclear fallout could be spread around by winds. So generally only missions where it is required because there isn't any sun light like a mission to Pluto do they use nuclear reactors.

      • Re:Nuclear batteries (Score:5, Informative)

        by Tweenk (1274968) on Wednesday October 29, 2008 @08:20AM (#25553547)

        Those are not nuclear reactors, but radioisotope thermoelectric generators (RTGs). Rather than harnessing the energy from steam heated by the fission of heavy nuclei, they get the power directly from the heat of natural decay of radioactive isotopes using thermocouples. Link. [wikipedia.org]

        Current nuclear reactor designs, even the compact ones used on ships and submarines, are too large and too heavy to be sent into space.

        • Re: (Score:2, Informative)

          by Spotticus (1356631)
          Not entirely true, there have been several missions (not recently) where full blown nuclear reactors have flown. Between 1971 and 1988 the Soviets flew 31 RORSAT missions using the BES-5 nuclear reactor. The US launched one mission in 1965 carrying the SNAP-10A reactor. Both types used liquid sodium cooling and were extremely compact and lightweight. The advantage of not requiring shielding
      • What bothers me is that the politicians push a requirement like that on the schools. It's FUD and it does nothing but enhance the public fears. The RTG's are designed to survive a launch vehicle failure as well as the subsequent impact when it falls to the ground. There won't be "nuclear fallout".
    • Re: (Score:2, Insightful)

      by hysonmb (814899)
      I agree that nuclear batteries would be a great idea in theory. I'm not a NASA employee, or scientist, but I would venture a guess that the risk is not worth the reward just yet. Imagine the first time one of those suckers breaks apart on liftoff.... "We're sorry ladies and gentlemen, Florida is now closed. We hope you enjoyed your stay and we look forward to seeing you when we reopen in 30 years. Thank you and goodbye."
      • Re: (Score:3, Insightful)

        by Reapman (740286)

        I'm pretty confidentent that even a catostrophic failure wouldn't create a nuclear meltdown even remotely like that. I could see the nuclear material falling to the ground and needing a cleanup crew to take care of it as a worst case, but I can't see something like this creating a new Cherynobyl (spelling probably off missing my coffee this morning) unless someone REALLY screws up.. but if your worried about that you should probably be more worried about them wanting to install new nuclear powerplants then

      • Re: (Score:3, Funny)

        by ColdWetDog (752185) *

        "We're sorry ladies and gentlemen, Florida is now closed.

        That would be a feature, not a bug.

    • Re:Nuclear batteries (Score:5, Informative)

      by Catmeat (20653) <mtm@s y s . uea.ac.uk> on Wednesday October 29, 2008 @08:50AM (#25553881)
      In this case, they aren't necessary as the lander has done all the science it was planned. What's the point of keeping it alive over the winter of all it's going to do in the spring is repeat the measurements it's already taken?

      RTG's [wikipedia.org] and RHU's [wikipedia.org] are a massive, expensive, pain in the ass and are best avoided unless absolutely necessary.

      Basically -

      • They're heavy. They are must be designed to wishstand re-entry intact and not disperse Pu238 fuel everywhere if the rocket explodes during launch. Extra weight on the lander means there will be science instruments that have to be taken off.
      • They're on 24/7 and they're only about 5% efficient so they produce about 20W of heat for every W of electricity. This is a huge problem when the spacecraft is buttoned up in it's Mars-entry aeroshell during the 9 month trip to Mars. Hundreds of W of waste heat must be dumped somehow or your lander will cook.

        This may well use some kind of fluid cooling loop that circulates through radiators on the crusie stage. This now gives you added problems of a pump (which must not fail or you'll lose the mission, so add a back-up pump) and how to disconnect the coolant pipes with absolute reliability when the time comes to ditch the cruise stage and enter the Martian atmosphere. More problems, cost and weight.

      • Pu238 is on every terrorist's Christmas wish-list. You have the added problems and of turning the spacecraft assembly facilities into highly secure spacecraft assembly facilities. Assembling a Mars lander is already hard and expensive. You really don't want to add to this the cost and disruption of post-9/11 anti-terrorist, security paranoia. Donna Shirley discusses this in her book on the Mars Sojurner rover, and that was put together back in 96.
      • Re: (Score:2, Funny)

        by Anonymous Coward

        Pu238 is on every terrorist's Christmas wish-list.

        Even the Islamic ones? Or don't they count?

      • You also have the problem of rabid freaks on usenet droning on and on about Cassinni and how all life on earth will cease to exist if something goes wrong during the launch.

        Personally, I think we should be mining plutonium on the moon and doing final assembly on-site. With robots that look like ants.

    • The weight of the shielding casket that would survive reentry on launch failure may be prohibitive. But I'd guess mostly environmentalists who don't want nukes going into outer space.

  • Maybe it's not the right place to post this:

    But I remember i was pretty excited in the days after the probe landed, checking the website everyday to see the news. I still check it once in a while.

    But what was the major finding finally ?

    I know they were not expectig to find life. But any indirect evidence of it would have been cool. They did find water ice, (and found it many times apparently ;-)

    just a bit disappointed I guess

  • Remember the story a little while back about them making some sort of discovery that they had to go to the President for before releasing to the public? Did we ever find out what that was..?
  • You have to hand it over to the NASA engineer crew - they can built their landers tough. Considering the distance and sheer hostility of the mars surface, going above the estimated 90 days of operation is a jaw-dropping exploit. Think about it for a moment - if they can double the operating time of the mars lander, this means that they will have managed to squeeze TWO complete mars missions using the budget of a SINGLE ONE. This will also have saved them several YEARS of labor and time investment that would
  • Given that it isn't atall mobile.
  • by heroine (1220) on Wednesday October 29, 2008 @12:06PM (#25557523) Homepage

    Obama could make it run for another year.

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