Opportunity examines basaltic Bounce, while Spirit heads for the hills

PASADENA, Calif. (April 1, 2004) -- During the coming weekend (April 3 and 4), the Mars rover Spirit will pass the 90-day mark since it bounced down on the red planet on Jan. 3. Although the vehicle was built to last 90 days, NASA mission engineers and scientists now think that Spirit and its twin rover, Opportunity, could still be roaming the Martian surface in August and even September.

The scientific instruments and the engineering systems are working well on both rovers, report mission managers who had worried that Martian dust would settle on the solar panels and choke off precious sunlight.

The dusty Martian atmosphere has cleared significantly and the threat of reduced sunlight has diminished, said Jim Bell, Cornell associate professor of astronomy and the lead scientist on the two rovers' panoramic cameras, at a NASA press briefing at the Jet Propulsion Laboratory in Pasadena on April 1. "Dust in the Martian atmosphere is down by a factor of two," he reported.

Bell explained that to date the two rovers have taken a total of 20,000 images, of which 16,000 are from the panoramic cameras and the remainder from the hazard avoidance cameras (hazcams) and the navigation cameras (navcams). The images amount to 2.3 gigabits of data.

Meanwhile Opportunity, which has been on Mars for 65 Martian days, or sols, has imaged the jagged rock struck by its deployed airbags when it bounced down on Jan. 24. Mission controllers have aptly named the rock "Bounce" and have instructed the rover to use its robotic instrument arm to get a close-up view of the rock with its microscopic imager.

Opportunity first spotted Bounce when it was still in Eagle crater, where it came to rest after its landing. But scientists could not determine if the distant object was, indeed, a rock until they got a close-up look. "It's a rock," said Bell at the press briefing, "and it's an interesting one at that. It's different than what we've seen before."

Bell says that Bounce -- about 40 meters from Eagle crater -- is covered with iron dust. After using the rock abrasion tool to grind away a clean hole, the mission scientists believe it is mostly a basaltic specimen, composed of volcanic iron minerals. It is the first time that that this type of rock has been seen during the rover mission.

Spirit, in the meantime, is on a record-breaking journey toward "Columbia Hills," about two kilometers from its current position in Gusev crater. NASA engineers believe it will take the vehicle about 40 sols to reach the base of the hills.