Mars rovers hunker down to weather space sandstorms
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After three years on Mars, NASA rovers built for a three-month mission face their toughest foe: Martian sandstorms blocking the sunlight that charges their batteries.
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Clearing dust storms on Mars allow Nasa's robotic rovers to increase their workload.
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It's been a watershed year  of science for&nbsp;the NASA&nbsp;Mars rover Spirit,&nbsp;a  six-wheeled&nbsp;automaton&nbsp;that continues to probe the red planet's  secrets&nbsp;as it clambers up the Columbia Hills.
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NASA's Opportunity Mars rover has come across  an interesting object&nbsp;-- perhaps a meteorite sitting out in the open at Meridiani  Planum. Initial data taken by the robot's Mini-Thermal Emission Spectrometer  (Mini-TES) is suggestive that the odd-looking rock is made of  metal.
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SAN FRANCISCO: Pictures of Earth-like clouds were captured by Nasa&#39;s Mars rover on Wednesday. Reports also indicate that there&#39;s a rock that doesn&#39;t look like anything scientists have ever seen.
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Two animations allow viewers to "hang-glide" over terrain currently being explored by Nasa's Mars rovers.
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LONDON - 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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One of the Mars rovers that have spent most of the past year studying the ruddy rocks and soil on the Red Planet is now taking a close look at some of the junk it shed during its fiery descent last January.
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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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Three years after the two Mars rovers were expected to stop working, they're still exploring the red planet, having shut down for the better part of two months because of dust storms.
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Almost by accident, NASA&#39;s Mars rover Opportunity has found a rock that may point to a second water event in the red planet&#39;s past.
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PASADENA, Calif. NASA thinks its Mars rovers just might keep going and going and going. The space agency has funded another extension of their mission, for an additional six months, if they last.
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The twin rovers  on Mars are in good shape today despite widespread dust storms that worsened last week  and threatened to cut off solar power to the robotic explorers.
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LOS ANGELES - NASA&#39;s Mars rover, Opportunity, has found more signs that rocks on the Red Planet were once submerged in water. Data sent by Opportunity suggest a crater was drenched a second time after drying out, scientists said.
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Description: An investigation into the loss of Britain&#39;s Beagle 2 spacecraft last December suggests the cause may have been unusual Martian weather.
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After surviving near fatal dust storms on Mars, NASA&#39;s Opportunity rover is gearing up for its long-awaited trek inside an expansive crater on the red planet&#39;s surface.
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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