Mars Rover Struggles to Weather Severe Dust Storm
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The hardy Mars rover Opportunity is struggling to stay alive  amid a severe and long-lasting Martian dust storm -- posing the greatest threat so far to the unexpectedly long-lived vehicle.
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A severe dust storm is underway on Mars, causing an energy crisis for NASA's Mars rovers. Dust in the atmosphere over Opportunity has blocked 99 percent of direct sunlight, leaving only the limited diffuse sky light to power the rover.
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NASA&#39;s Mars rovers have uncovered more tantalizing evidence of a watery past on the Red Planet, scientists said Wednesday. And the rovers, Spirit and Opportunity, are continuing to do their jobs months after they were expected to ...
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The twin rovers on Mars - now reviving having survived the freezing depths of Martian winter - have found new signs that water was once plentiful on Mars.
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NASA (news - web sites)&#39;s Mars rover Opportunity will back its way out of a crater it has spent four months exploring after reaching terrain that appears too treacherous to tread.
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In the next few weeks the twin Mars rovers will be out of touch with Earth when the Sun lines up to block communications. Daily operations will be taken over by longer-term instructions without radio links between the two planets.
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Extreme PlanetThough both rovers are exploring Mars well beyond their initial 90-day missions, electrical connections and moving parts are showing signs of temperature-related fatigue.&quot;Every day we have a huge thermal cycle,&quot; notes Jake Matijevic, chief of the rover engineering team. &quot;That causes the solder in electrical connections to expand and contract until it breaks.&quot;Seasonal ChangeDuring their exploration of Mars, the rovers have recorded temperatures ranging from midday highs of about 35 degrees C. (95 degrees F.) in spring and summer to nighttime lows of about minus 110 degrees C. (minus 166 degrees F.) in winter. Spirit has experienced greater swings in temperature because its location is farther from the martian equator, which puts it seasonally closer to or farther from the Sun than Opportunity.Three Years of DataRover engineer Dan Porter has been tracking temperatures recorded by 50 or so sensors on each of the rovers since shortly after they landed on Mars in January 2004. The results are not only of interest to scientists, they're a favorite of human audiences as well.&quot;People ask about this all the time,&quot; says New Mexico geologist Larry Crumpler, a member of the Mars rover science team who created the charts showing monthly average temperatures superimposed on panoramic-camera images from each of the rovers. &quot;These plots of daily temperature are destined to become an important part of all my public outreach talks.&quot;Cold vs. ColderJust as on Earth, temperatures on Mars are not uniform everywhere. Objects exposed to direct sunlight are apt to be warmer than those in the shade. Some objects retain heat better than others. A source of relative warmth on Mars is rocky terrain, because it retains heat better than sandy terrain.A solar panel is sort of like a &quot;warm wall in mid-winter,&quot; says Crumpler. Components beneath the solar panels, such as the hazard avoidance cameras, are closer in temperature to the martian air. Unlike Earth, Mars does not have a thick, atmospheric blanket to seal in warmth by night or minimize the Sun's heat by day.Wear and TearEngineers have traced stalls in a shoulder joint on Opportunity's robotic arm to a broken electrical wire. The shoulder motor has experienced greater temperature swings than other parts because of its location beside a heater that has been stuck in the &quot;on&quot; position since shortly after landing.Notes Matijevic, &quot;Our theory is that one of the wires in the electrical coil broke free and disabled the motor.&quot;Mechanical ProblemsExtremely cold temperatures have also caused mechanical problems. Recently, Opportunity's right front wheel began drawing excess electrical current, reminiscent of Spirit's right front wheel in 2004. The demand for more electrical current suggests that the wheel motor is working harder than usual. Engineers suspect that, like motor oil that can't handle freezing temperatures on Earth, gelid lubricant failed to flow properly and caused Spirit's right front wheel to fail.Adjusting ExpectationsRover drivers have compensated for Spirit's stuck wheel by driving on the other five wheels. They have compensated for Opportunity's stalled shoulder joint by unstowing it before going to sleep at night. This way, if the motor fails during the night, when temperatures are at their lowest, they would still have limited use of the arm by operating the remaining working joints. Each rover has lost a few temperature sensors as well, while dozens more continue operating.Time Will Tell
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An unexplained phenomenon akin to a space-borne car wash has boosted the performance of one of the two US rovers probing the surface of Mars, New Scientist magazine said on Tuesday.
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An unexplained phenomenon akin to a space-borne car wash has boosted the performance of one of the two U.S. rovers probing the surface of Mars, New Scientist magazine said on Tuesday.
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NASA's Mars  rover Opportunity&nbsp;will back its  way out of a&nbsp;crater it has spent four months exploring after reaching terrain&nbsp;that appears  too treacherous to tread.&nbsp;
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While those unflappable interplanetary twins - Spirit and Opportunity - continue to trudge across Mars, engineers and scientists are readying the next robotic rover destined to trail across the distant sands of the red planet.
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The Opportunity Mars rover has turned into a junkyard dog, prowling ever closer to a hunk of space litter at Meridiani Planum -- a discarded heat shield.
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Scientists said Friday they are plotting the next move for the Mars rover Opportunity, which reached the edge of a deep and geologically rich crater last week after a marathon trek.
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The Mars Rover Opportunity has  arrived at the rim of a big crater that scientists never  thought it could reach, NASA said on Wednesday.
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Mission scientists worry that nearly a month's worth of storms could permanently damage or disable the Mars rovers exploring the Red Planet.
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SPACE.com / BOULDER, Colorado-It has been a long, hard drive on Mars for NASA's Opportunity rover.
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NASA&#39;s Mars rovers don&#39;t seem to be wearing out so mission planners have begun to think more boldly, including a plan to let one climb up a steep &quot;escape hatch&quot; from a crater it has been exploring and set out on a trek across a plain.