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Mars Lander Faces Slow Death

Posted by Soulskill on 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.'"

10 of 212 comments (clear)

  1. NASA by Sasayaki · · Score: 5, Funny

    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.

    --
    Check out my sci-fi book "Lacuna" at http://goo.gl/MVxX8
  2. Well, it's been a great track record lately... by BTWR · · Score: 5, Insightful

    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.

    1. Re:Well, it's been a great track record lately... by BTWR · · Score: 5, Interesting

      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.

    2. Re:Well, it's been a great track record lately... by savuporo · · Score: 5, Interesting

      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.

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  3. Re:Why heaters? by MichaelSmith · · Score: 5, Informative

    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.

    --
    http://michaelsmith.id.au
  4. Re:Why heaters? by jm1234567890 · · Score: 5, Informative
    From the article

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

  5. Re:what I do not understand. by timmarhy · · Score: 5, Funny
    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.

    --
    If you mod me down, I will become more powerful than you can imagine....
  6. Happy to help a fellow geek by MichaelSmith · · Score: 5, Funny
    ...with Melbourne conversation starters.
    • Don't you just hate rugby?
    • Funny October we are having. Almost as hot as February.
    • Washed your car lately? Of course not (water restrictions)
    • Sorry you are missing the Melbourne Cup? Do you like boozing up in the Flemington car park?
    • What did you think of the Grand Final? Sorry that bunch of wankers from Hawthorn won it. Thought we had seen the last of them.

    Should be enough to get going. No boobytraps there. I promise.

    --
    http://michaelsmith.id.au
  7. Re:what I do not understand. by Dr.M0rph3us · · Score: 5, Interesting

    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).

  8. Re:Nuclear batteries by Catmeat · · Score: 5, Informative
    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 and RHU's 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.