Slashdot Mirror


Spirit Outlasts Viking 2 Lander

ScottMaxwell writes "Spirit, the Mars rover designed for a 90-day mission, has now outlasted the Viking 2 lander. Viking 2 survived until its 1281st sol (Martian day); Spirit is now on sol 1282 and counting. Assuming both rovers continue to weather the ongoing dust storms, Spirit's sister, Opportunity, will reach the same age in a few weeks. They aren't breathing down the neck of the all-time record just yet, though — the Viking 1 lander lasted 2245 sols on the surface of Mars; Spirit and Opportunity won't break that record for another 2.7 Earth years."

7 of 137 comments (clear)

  1. Nuclear powered by FTL · · Score: 5, Informative
    Mars lander trivia:
    • Both Viking landers were nuclear powered (RTGs).
    • So are both of the rovers, to a certain extent. Both rovers contain slugs of plutonium which keep the electronics boxes warm and reduce the amount of solar power needed for heating.
    • Viking 2 lasted 1281 sols and died when its batteries failed. Although the RTGs would have produced usable power for another ten years, the power levels were too low for 70s electronics. So the RTGs would slowly charge the batteries then the batteries would power up the lander for short durations.
    • Viking 1 lasted 2245 sols and lost contact with Earth when a bad command was sent which instructed Viking to point its antenna in a different direction (sort of like typing "shutdown -h now" on the command line of a remote server, there's no recovery short of a house-call).
    --
    Slashdot monitor for your Mozilla sidebar or Active Desktop.
    1. Re:Nuclear powered by nelsonal · · Score: 3, Informative

      From the summary, it looks like sunrise/sunset cycle on the local planet (~24 hours on earth). My knowledge of the solar system is fuzzy (it's been a long time since I was a "junior astronomer" but I think the martian day is about 25 Earth hours (their year is considerably longer, though).

      --
      Degaussing scares the bad magnetism out of the monitor and fills it with good karma.
    2. Re:Nuclear powered by Anonymous Coward · · Score: 5, Informative

      A 'sol' is a day in local time. Different planets rotate at different speeds making the length of their days different. One sol on Earth is 24 hours. One sol on Mars is 24.5 hours. One sol on Venus is a staggering 243 Earth days.

    3. Re:Nuclear powered by C0vardeAn0nim0 · · Score: 3, Informative

      because not everyone in the world speak english. and nasa colaborates wit the ESA, wich is composed by many countries wich speak latin languages (portuguese, spanish, french, italian,...). and "sol" comes right from latin.

      it's all about being nice with their partners.

      --
      What ? Me, worry ?
  2. Re:NASA by TheSuperlative · · Score: 5, Informative

    Got me on Challenger, but Columbia, no. The shuttles were all designed with a 10-year lifespan in mind - they have more than outlasted that expectation

    --
    "In God we trust, all others we monitor." -- Unofficial NSA motto
  3. Sorry, not Barry Bonds here by Tablizer · · Score: 5, Informative

    that needs a big fat asterisk. Seriously, a "90-day mission" and it's still going 3 years later? Something is rotten in Mars.

    Most thought that dust on the solar panels would end the missions after a few months. Turns out that whirlwinds clean them every now and then. They didn't know such would happen since long-duration solar missions hadn't been done yet.

    And mechanics *are* wearing out, it is just that they find workarounds. Spirit drives backward because of a failed wheel, and Oppy holds its elbow in a single place most of the time, using wheels to maneuvor instead of bend the bad elbow. And some if it is probably luck; the electronics could snap at any time due to heat-cold cycles. (Oppy's front wheel is showing signs of wear also.)

    It is also true that statistically, once missions get past the early phase, they tend to last well. The failure spots are usually early in most missions if there are failures.

  4. Re:Oh my goodness me by big-magic · · Score: 4, Informative

    Assuming I counted correctly, there have only been 5 successful landers/rovers (Viking 1 and 2, Mars Pathfinder, Opportunity, and Spirit) and 1 partial success (Mars 6). Check the page http://en.wikipedia.org/wiki/Exploration_of_Mars. There were a lot more missions to Mars than I realized, most of them failures. Going to Mars is hard, which makes the success of Opportunity and Spirit even more amazing. It would be a mistake for us to get cocky and think we've got this mastered, just because our couple missions went really well.