This undated handout is a NASA illustration of one of its two six-wheeled rovers，Opportunity and Spirit, operating on the surface of Mars, searching for geological evidence about water in the bygone Martial environment. (Xinhua/Reuters Photo) Photo Gallery>>>

    LOS ANGELES, Nov. 11 (Xinhua) -- Due to massive Martian dust storms, NASA's Spirit Mars rover is running out of power, it was announced on Tuesday.

    Spirit last communicated with Earth on Sunday, when it reported that its solar arrays had produced just 89 watt-hours of energy, which is much less than the rover needs in a day, the Jet Propulsion Laboratory (JPL) said.

    The news came only a day after NASA declared an end to the Phoenix mission to Mars' north pole, the first to sample ice on an alien planet. Dust storms and the approach of winter in the northern hemisphere were blamed for Phoenix's demise.

    It is also the least power that either Spirit, or its twin, Opportunity, has produced over the entire life of the mission, which began in 2004.

    Spirit's survival might be in jeopardy because the dusty arrays were producing only a third as much power as they were capable of, even before the latest dust storms hit, said John Callas, the rover project manager at JPL in La Canada Flintridge near Los Angeles.

    The storms of the last few days have reduced the output even more to 26.5 percent, he said.

    The low power levels probably tripped a built-in fault-protection system, which automatically disconnects nearly all the rover's electronics from its batteries to keep them from draining completely. When that happens, mission managers on Earth lose control of the vehicle, Callas said.

    "The best chance for survival for Spirit," Callas said, is to avoid a low-power trip, from which the rover might not awake. To avoid draining the batteries, mission managers sent a message to the rover today, ordering it not to communicate with Earth until Thursday when the dust storms have cleared and the solar panels produce more power.

    Meanwhile, Opportunity, which has not been compromised by the dust storms to the same extent, is driving to a deep crater.