Passage 3 Future Uncertain for Stuck Mars Rover
“精神”與“機(jī)遇”，同生不同命 《今日美國(guó)》
[00:01]Spirit has always been the unluckier of NASA's twin Mars rovers.
[00:08]Just weeks after landing in a Martian crater in 2004,
[00:15]it wasn't fuctioning well and transmitted gibberish to Earth.
[00:22]Engineers eventually nursed it back to health.
[00:26]As if the near-death experience wasn't enough,
[00:31]Spirit was upstaged early on by its twin Opportunity,
[00:37]which landed in a geologic gold mine and was the first to determine
[00:42]that the frigid, dusty planet possessed a wetter past.
[00:49]Bad luck has fallen again on Spirit.
[00:53]As the workhorse rover marks its sixth year on the red planet on Sunday,
[01:01]it finds itself stuck in a sand trap, perhaps forever.
[01:07]The six-wheel robot geologist has been in jams before,
[01:13]but this is the worst plight yet.
[01:17]With Martian winter arriving in several months,
[01:22]Spirit may not have enough power to keep going
[01:27]unless scientists can point the solar-powered rover toward the sun.
[01:34]The latest misfortune occurred in April when Spirit,
[01:39]driving backward because of a lame wheel,
[01:44]broke through the crusty ground like a person falling through a frozen pond
[01:50]and got stuck in fluffy sand.
[01:54]NASA was dealt a major setback recently
[01:59]when another wheel appeared to have stopped moving,
[02:03]leaving Spirit with only four working wheels to plot its great escape.
[02:11]It's been a particularly rough year for Spirit.
[02:17]Besides getting stuck in a sand rut,
[02:20]it suffered periodic bouts of memory loss
[02:25]and other sufferings including sudden computer reboots.
[02:30]Though the forecast of getting Spirit out looks bleak,
[02:36]scientists are not ready to give up yet.
[02:41]But if they exhaust all escape options,
[02:44]they will switch to Plan B and try to lean the rover to the north
[02:51]where it can get more sunshine to keep running
[02:54]so that it can continue to do science in one spot.
[02:59]Unlike a rover, which performs science experiments as it wanders,
[03:06]a lander studies its surroundings while stationary.
[03:11]Fortunately for researchers, what may turn out to be
[03:15]Spirit's final resting spot looks like a scientific godsend.
[03:21]The sand is rich in sulfate, a mineral that forms in the presence of water.
[03:29]Originally designed as a three-month mission,
[03:33]Spirit and Opportunity have operated past their warranty.
[03:39]Spirit and Opportunity are also closing in on the record
[03:44]for longest-running Mars surface mission currently held
[03:49]by the Viking 1 lander, which operated on the planet for six years and 116 days.
[03:59]Opportunity didn't have to work hard to impress scientists
[04:05]because it jumped to an ancient lakebed flooded with minerals
[04:10]that pointed to geologic evidence of past water.
[04:15]Spirit, on the other hand, touched down in the rugged rock plains of
[04:22]a crater on the opposite side of the planet
[04:25]and had to trek toward the hills to make discoveries.
[04:30]With Spirit immobile, it's still snapping pictures of
[04:35]its surroundings and sending data back to Earth.
[04:41]Spirit's next challenge will be surviving the upcoming Martian winter.
[04:47]Meanwhile, Opportunity has been busy grinding into a dark-toned rock
[04:54]that scientists think may be a stony meteorite.
