Mars Is Dust Great!

Effort to Clear Path of Mars Rover Fails
By ANDREW BRIDGES

PASADENA, Calif. (AP) - NASA's efforts to clear the way for the Spirit rover to reach Mars' surface have so far failed, and engineers are considering alternative routes for maneuvering the six-wheeled robot off its lander, scientists said Thursday morning.

NASA planned to try one more time to gather up the deflated air bags that cradled Spirit during landing but now blocks the ramp engineers want to use as the rover's exit to the Martian soil.

``We were not successful in doing that yesterday,'' said Matt Wallace, mission manager for Spirit's sixth day of operations.

The earliest Spirit would leave the lander now is Wednesday. Further delays are possible if NASA opts to send Spirit down an alternative ramp, turning either 120 degrees to the right or 60 degrees to the left, which would be a greater risk for the $820 million mission.

Even while perched atop its lander, Spirit has begun doing science work, including snapping high-resolution pictures of its immediate surroundings. It completed a full color panorama of its surroundings, which should reach Earth in the next few days.

Initial analyses of the earliest images from Spirit suggest the landing site inside Gusev Crater is not the pristine dry lake bed scientists originally had hoped.

That indicates the robotic explorer's hunt for geologic evidence that the planet once was a wetter place conducive to life might be more difficult than expected.

The Mars Exploration Rover project also includes a second, identical rover, named Opportunity. It is scheduled to arrive on Mars on Jan. 24.

Spirit, swaddled in its air bags, bounced about 25 times after hitting the surface during its landing Saturday, said Rob Manning, manager of the entry, descent and landing portion of the mission. On its first bounce, Spirit rose an estimated 26 feet.

It came to a rest to the south of a cluster of impact craters seen in the three images its lander snapped in the seconds before landing.

``We could go explore those,'' Manning said.

Scientists have received the first data from Spirit's mini-thermal emissions spectrometer, which determines the mineralogical composition of the rocks and soils it views.

Once the data are interpreted, probably over the next few days, they should help scientists pick the first targets Spirit will investigate close-up.

Scientists selected Spirit's landing site because they believed the broad crater once contained a brimming lake - the type of place that may have been hospitable to life. If that was the case, Spirit should be seeing a flat plain rich in fine-grained sediments, said Ray Arvidson, of Washington University, the mission's deputy principal scientist.

``That's not what we're looking at,'' Arvidson said.

Spirit's first look suggests if the landing site was ever a lake bed, it has been significantly altered by other geologic processes. What they might have been remains the subject of intense debate among mission scientists.

On the Net: http://marsrovers.jpl.nasa.gov