Update: Mars Rovers Weather the Storm
A time-lapse image of the dust storm's progress from the Opportunity rover, from June 14, 2007 through July 19, 2007. The images are approximately true color composites, generated using data from the rover's panoramic camera's various filters. The numbers across the top of the image report a measurement of atmospheric opacity, called "tau." The lower the number, the clearer the sky.
Credit: NASA/JPL-Caltech/Cornell

A global dust storm at Mars continues to veil the two surface rovers and their solar panels, but NASA officials reported today they expect the robots are capable of weathering the tempest.

The situation grew steadily worse after the first storm started in mid-June, leading to a global dust shroud. But in recent days the situation has improved. Still, until the storm abates, the robots' operators on Earth will be on alert.

The rovers rely on sunlight to charge their batteries and keep vital electronic parts warm. The space agency plans to keep the rovers on a low-energy diet for the time being, transferring data from the Martian surface only once every three days until the storm dies down.

"We are still waiting out the storms, and we don't know how long they will last or how bad they will get," said John Callas, rover mission manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif.

The rover Spirit now is weathering the dustiest sky it has ever recorded, though not as severe as what its twin, Opportunity, faced a week ago. NASA, however, has said Opportunity is still the most vulnerable because of a heater switch that has been stuck in the "on" position since landing day in January 2004.

Each rover has eight radioactive heaters in addition to electric heaters for keeping batteries and electronics within safe operating temperatures. While the plutonium-powered heaters aid the rovers' survival on low-power days and through extremely cold nights, the electric heaters are also necessary.

  • Mars Rovers' Top 10 Most Amazing Discoveries
  • SPECIAL REPORT: Mars Rovers
  • VIDEO: Mars Rover Team Ponders Mission's End