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End of the Road For NASA's Mars Rover?

Posted by CmdrTaco on from the hello-up-there dept.

An anonymous reader writes "NASA celebrated Mars rover Spirit's bountiful, six-year stint on the red planet on Sunday – way longer than its forecast three-month mission. But it all may soon come to an end, stuck as it is in Martian sand."

4 of 181 comments (clear)

  1. Re:Spoiler: Why it's dying; emits one last factoid by Chris+Burke · · Score: 4, Informative

    Does it need continuous power to stay capable of operating?

    Yes. It requires some nominal amount of power for heating to avoid freezing and damaging components. This is what happened to the Phoenix lander (as anticipated in that case). With the panels covered in dust, plus the additional cold and lack of sunlight during the winter, Spirit is unlikely to survive the winter unless something changes.

    --

    The enemies of Democracy are
  2. Re:Way to go, NASA! by Guysmiley777 · · Score: 3, Informative

    The USSR bounced plenty of probes off and past Mars before and after the Mars 3 lander. Getting onto the surface of Mars is no trivial task. I think they had 7 failures (not including launchpad kerfuffles) where the probe either stopped responding, missed the planet or created a new crater.

    --
    Coding with assembly is like playing with Legos. Coding an application in assembly is like building a car with Legos.
  3. Correction of misinformation by tlambert · · Score: 3, Informative

    "The rovers run a VxWorks embedded operating system on a radiation-hardened 20 MHz RAD6000 CPU with 128 MB of DRAM with error detection and correction and 3 MB of EEPROM. Each rover also has 256 MB of flash memory. To survive during all of the various mission phases, the rover's vital instruments must stay within a temperature of 40 C to +40 C (40 F to 104 F). At night the rovers are heated by eight radioisotope heater units (RHU) which each continuously generate 1 W of thermal energy from the decay of radioisotopes, along with electrical heaters that operate only when necessary. A sputtered gold film and a layer of silica aerogel are used for insulation."

    http://en.wikipedia.org/wiki/Mars_Exploration_Rover

    -- Terry

  4. Yes, it needs power; here's why by tlambert · · Score: 4, Informative

    Tthe OS reboots periodically if there's no communication to ensure that it doesn't hang because of the OS. It's a hardware watchdog, which is NOT shut down when the rover is put to sleep, so it will wake periodically over the winter, try to establish communications, ask for a software update (if any), and then go back to sleep. Given that the original mission anticipated a 90 life expectancy, expect these reboots to be relatively frequent.

    http://www.flightsoftware.org/files/FSW08_Deliman.pdf

    -- Terry