Still Exploring After Martian Winter, Rovers Send Back More Signs of Water
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The two roving vehicles Spirit and Opportunity have explored Mars about three times as long as originally scheduled and keep finding evidence of past liquid water.
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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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The twin Mars rovers have found a wonderland of weird rocks and enticing dunes along with more evidence the Red Planet once had water, NASA scientists said Wednesday.
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By RANDOLPH E. SCHMID Associated Press  WASHINGTON -- An orbiting spacecraft has sent back new evidence for the presence of water on Mars.    Scientists long have debated whether water flowed on the red planet, with evidence increasing in recent years.
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NASA has funded another extension of their mission -- an additional six months, if they last. Word from the Jet Propulsion Laboratory is that NASA has regained reliable contact with the rovers Spirit and Opportunity
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It&#39;s the discovery by two Mars rovers that the Red Planet once had water and possibly could have supported life. That recognition comes today from the journal Science.
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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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LIVELY MARS : ET might just be out there. NASA&#39;s two Mars rovers, Opportunity and Spirit, landed on the Red Planet early in 2004 and have since found conclusive evidence of water that could possibly have harboured life.
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NASA is paying for the Mars Rovers to keep working. The twin rovers &quot;Spirit&quot; and &quot;Opportunity&quot; landed on the surface of Mars last January.
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NASA&#39;s Mars rover, Opportunity, has discovered more evidence that water may have flowed over rocks on the Red Planet. Data sent back by Opportunity suggests an area known as the Meridiani Planum, was drenched
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THE Mars rover Opportunity has found new evidence of past existence of water on the Red Planet, NASA said today. Opportunity keeps finding new clues of past water as it continues probing Mars, said mission
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Almost by accident, NASA's Mars rover Opportunity has found a rock that may point to a second water event in the red planet's past.
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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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Spirit, one of the two rovers exploring Mars, has discovered the first rock on the planet that scientists say could have formed only in water - - but whether the water was flowing, or lay like a shallow sea that came and went, remains unknown, the mission
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LOS ANGELES - NASA&#39;s Spirit rover has found more evidence of past water on the hills of Mars, while its twin, Opportunity, has observed a field of dunes inside a crater.
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The Mars rover Opportunity has sent back its first color panorama of the large Martian crater it recently reached after a 21 month trek, and NASA scientists could barely contain their excitement about what they found.
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The Mars Reconaissance Orbiter sends back images supporting theories that water once existed  -  or could still exist  -  on the red planet