Rover Sits Tight as Engineers Try to Sweep an Air Bag Aside

NASA’s Spirit rover sent back another high-definition color picture of Mars on Thursday, a view north from the rear of the lander showing Sleepy Hollow, a depression that mission scientists think may be the first destination when the rover rolls off the landing platform sometime next week.

But officials at the Jet Propulsion Laboratory in Pasadena said the roll-off might be delayed another day or so because a “lift and tuck” maneuver designed to retract one of the collapsed air bags did not work.

The maneuver left the lander sitting with “a slight list,” said James Bell of Cornell University. As a result, the latest photo looks as though the horizon is rising toward the right side of the frame. In actuality, the horizon is nearly flat, said Bell, who designed the camera.

The list will be corrected as scientists continue to try to free the air bag, one of the inflatable cushions that allowed the lander to bounce to a soft landing Saturday evening.

The slightly inflated air bag is at the end of one of the tiny ramps that the rover will use to roll from the larger ramps to the ground. Bell said the rover could probably roll over or around the air bag if necessary, but that would entail a small increase in risk and would be tried only as a last resort.

There are two other sets of ramps that the six-wheeled vehicle can use and, if the bag cannot be retracted out of the way during efforts Thursday evening, Spirit will probably use one of those routes, said JPL geologist Matt Golombek.

Engineers want to use the partially blocked ramp because the rover could simply roll straight ahead to leave the lander. To use one of the other ramps, it would have to first pirouette 120 degrees to the right to roll off in a forward direction, or 60 degrees to the left to roll off backward.

Bell said the rover has acquired a high-definition panoramic view of the entire area of Gusev Crater, but that only about 40% of the images have been sent back to Earth. Because they are such high-resolution images, each photo is a large data file requiring a significant amount of time to be transmitted.

“Over the next two, three or four sols [Martian days], we’ll trickle down those images and have the whole panorama in hand,” Bell said.