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NASA Extends Rover Occupation of Mars

Posted by CmdrTaco on from the wait-till-they-try-to-occupy-us dept.

iocat writes "Reuters reporting that NASA is extending the Rover missions on Mars by another five months. However, they point out that while the rovers look poised to greatly exceed their planned life cycle, they could basically die at any time. Still, it will be cool to see a little more exploration."

8 of 206 comments (clear)

  1. Almost first post by Pi_0's+don't+shower · · Score: 4, Interesting

    I wonder how much terrain these rovers can explore in 5 months, or if they're basically useless because of range limitations?

    1. Re:Almost first post by AKAImBatman · · Score: 4, Interesting

      The difficulty is in their solar panels. Eventually they collect so much dust that they don't generate enough power. Also, the rovers stay very still at night to conserve power.

      Interestingly enough, the engineers nearly had an RTG working for the Rovers. Unfortunately, the outcry about Cassini pretty much killed that. It's too bad, because with an RTG, the power source would outlast the rest of the components by some 50 years!

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      Javascript + Nintendo DSi = DSiCade
    2. Re:Almost first post by Mal-2 · · Score: 5, Interesting

      Even with range limitations they're hardly useless. Both rovers landed in relatively fertile areas for exploration, and Opportunity would have still been a big success even if it proved unable to leave the crater it landed in. The main thing that comes to my mind is to find the edges of the ancient ocean and explore there -- partly because tidepools on Earth are teeming with life, and partly because shallow water means fossils (if present) won't be buried very deep. I noticed very early on that the rocks Opportunity was looking at looked an awful lot like tidepool rocks, at least ones from the eastern Pacific shore (the only ones I've seen firsthand). I knew there was good reason for NASA to be REALLY damn sure before announcing there was a lot of water on Mars at one time, but I pretty well was convinced as soon as I saw those distinctive wormholed rocks.

      However, it looks like their lifespan will be determined by a few factors, some of which are within human control and some which are not:

      1. Dust storms. Seems to me one good one would pretty well take a rover out of service from dust buildup on the panels alone.

      2. Equipment failure, particularly the "always on and draining power" type. One has already made Opportunity a little bit gimpy, but I doubt a single such failure would be fatal. Cumulatively, several would just be too much to bear.

      3. Shorter and/or darker Martian days as the seasons and distance from the sun change. This won't take out a rover outright of course, but they could compound the prior two problems. At least these events are predictable.

      4. The Martian Defense System finally tracks the rovers down and explodes them. Turns out the reason they didn't shoot the first time is they thought it was just another shipment of punching balloons for their nitrous oxide-fueled nightlife. Once they realize we sent ROVERS and not RAVERS, they're going to be mighty pissed off.

      Mal-2

      --
      How is the Riemann zeta function like Trump rallies? Both have an endless number of trivial zeros.
    3. Re:Almost first post by AKAImBatman · · Score: 4, Interesting

      Keep in mind that RTGs are passive devices, not reactors. As such, the radiation dosage will never exceed that of a pound of Plutonium-238. Plutonium-238 gives off a significant amount of radiation (half life of 87 years), but it's all Alpha particles. Since the Pu-238 is emitting Alpha particles, the radiation tends not to even make it through a piece of paper, much less the indestructible casing they pack these things in. Besides, the heat generated by the Alpha particles is what gives the RTG power. Doesn't make a whole lot of sense to let your power escape. :-)

      I'm still waiting for the first mission where they use SRGs (Stirling Radioisotope Generators). Those little stirling engines are far more efficient than the heat differential of RTGs. If the tech works out, it could even be a boon for lower powered devices on Earth. I figure that a tiny SRG with about 5-10 grams of Pu-238 or Sr-90 could power your cell phone for 50 years. A laptop (depending on the design) could be powered by 100-600 grams.

      --
      Javascript + Nintendo DSi = DSiCade
  2. Excellent! by qualico · · Score: 4, Interesting

    Its always good for future missions if the current ones exceed expectations.

    Looking at Mars, now a distant orange glow in the sky, it amazes me that we have intelligence there.

    Good job NASA.

  3. Let's hear it again for JPL by Steve+the+Rocket+Sci · · Score: 5, Interesting

    Pasadena's Jet Propulsion Laboratory (JPL) has done it again, it would seem. When the Voyager 1 and 2 missions were launched in 1977, they estimated that they would only last until the encounter with Saturn roughly four years later. Now, in 2004, they are still returning useful data, at a distance of over 90 AU from the Sun (in comparison, Pluto is only 40 AU from it). Sure, they had their problems during the mission, but it looks like Spirit and Opportunity may share a similar quality construction. It's definite that they won't last 27 years, but with how well they are functioning, I think the only limit will be the Martian dust collecting on their solar panels. When they Next Generation Rover lands on Mars in the latter part of this decade, it will hopefully use nuclear power, and overcome this obstacle.

  4. Re:unmanned missions by morcheeba · · Score: 4, Interesting

    I hate to argue with your logic, but here goes:

    Robots can run basically forever, until something breaks or they run out of juice.
    Somehow running out of this consumable is better than a human running out of their consumables (food and air)? If you want to be accurate, there are mechanisms for both to regenerate these consumables -- solar cells and plants.

    One unique thing about people (besides their intelligence) is their self-healing characteristics ... if a robot gets a little hole in a hydraulic tube, it'll leak until it's empty. A human would clot that blood and carry on. If a human breaks a leg, you can bet they'd figure out a way to complete the mission with just one leg... I wouldn't give a robot those odds, even if they lost only one of six legs.

    But, I agree.. unmanned missions are great, just for totally different reasons: low cost and hence, the ability to many missions to many different areas, each with new instruments designed to test theorys proposed by the results of previous missions. A human mission would blow the whole budget with just one trip.

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    HIV Crosses Species Barrier... into Muppets
  5. Name a rock, 'Tux' by Megaport · · Score: 5, Interesting
    Actually, my friend Merideth considers herself to be the feature-naming goddess for Spirit, so if /.ers will reply to this post with possible names, I'll put in one of the highest moderated ones for consideration.

    Hi Justin,
    How about we get the ball rolling by naming a rock 'Tux', after the Linux mascot penguin?

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