Dust Storms threaten Mars Rovers

Two Martian Rovers, Spirit and Opportunity, are trying to ride out the dust storms that are occurring on Mars. They continue to successfully weather these storms that are threatening to cut power to their solar panels. It is a day-to-day battle for survival.

The pervasive dust in the martian atmosphere and the settling of dust onto the machinery impedes the ability of the rovers’ solar panels to convert sunlight into enough electricity to supply their needs. One of the vital needs is to protect each rover’s “vital organs” of internal computer electronics, heaters and batteries from becoming so cold that something may snap.
Both rovers are in position to pounce on science targets. Spirit is ready to gather evidence for long-past explosive volcanic activity in an area dubbed Home Plate. While Opportunity is a mere 130 feet from the point where it will enter Victoria Crater.
These two rovers landed on the planet in January of 2004 and have wheeled across Mars for longer than their original 90-day warranties.

John Callas, project manager for the Mars Exploration Rovers at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California explains, “There is some suggestion that the storm may be breaking up. But that's on a global scale. What really counts is what is the weather doing over each of the rover sites ... and it's still troublesome.”

They are being careful about how much power they consume, so they are not doing any driving as of now. They are making daily science observations and feel Spirit is in good health. However Opportunity is suffering more than Spirit. Atmospheric opacity is still very high and solar array power available to the robot remains low (between 130-140 watt hours) at Opportunity’s locale. Opportunity is currently performing on bare-bones survival activities. The two concerns with Opportunity are: the need to keep the vehicle “power positive” (make sure that it generates more power than it consumes) and the need for the rover to keep its electronic innards warm enough.

If things get too tough for Opportunity, the vehicle will go invoke its onboard fault protection” capabilities. The vehicle will go into safe-mode and will not send data at all. It will use the power it has to stay warm and sleep all day only waking up for a short period each day to listen for commands from Earth.

Jim Bell, the NASA Mars Exploration Rover Project’s Panoramic Camera Payload Element Lead at Cornell University, calls it “a frustrating waiting game.” But he is “optimistic that the rovers will ride out this storm and then get back 'on the road' to do great science.”

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