Peek Into Crater Reveals More of the Same Martian Terrain

After traveling over the Martian surface for more than 30 days to reach the “Bonneville” crater, NASA’s Spirit rover peeked over the rim and found that the crater floor looked very much like the terrain it had already passed over, researchers said Thursday.

Notably absent in the 220-yard-diameter crater were rock outcroppings like those found by Spirit’s twin, Opportunity, halfway around Mars in a much smaller crater at Meridiani Planum.

Such outcroppings would have given the science team at NASA’s Jet Propulsion Laboratory in Pasadena a better idea of the rock composition below the surface at Gusev Crater, of which the Bonneville crater is a small part, and might have shed light on the question of whether large quantities of water once existed there.

The team has already confirmed that large quantities of water once existed at Meridiani Planum, where Opportunity landed Jan. 24.

Although the team has yet to take high-definition pictures of the interior of Bonneville, which might reveal unexpected details, it now seems likely that they will forgo the chance to drive the rover into the crater.

If the soil in the crater “is the same stuff we’ve been on and characterized already, then we’ll go where the object of the mission suggests, which is someplace else, basically,” said scientist Matt Golombek.

Spirit will most likely skirt the crater’s rim and head toward the East Hills about 1 1/2 miles away.

The new images of the crater show a layer of dusty soil punctuated by small rocks. On the far side of the crater, the images show the heat shield from Spirit’s lander, which crashed to the surface after the lander separated from it. In the distance, the same panoramic image reveals the lander’s parachute.

The two rovers turned their cameras to the sky this week. Spirit snapped a picture of Earth about an hour before sunrise. Spirit also snapped an image of a streak across the Martian sky that team members thought may be the National Aeronautics and Space Administration’s Viking 2 orbiter, which has been orbiting the Red Planet since 1976. Earth-based engineers have been unable to communicate with the orbiter for 20 years.

Opportunity, which has continued exploring the small crater in which it landed, captured images of Deimos and Phobos, Mars’ moons, as they crossed in front of the sun. The images will help astronomers characterize the moons’ orbits more precisely, enabling the European Space Agency’s Mars Express orbiter to turn its camera toward them.

JPL project manager Jennifer Trosper said the team expected each rover would survive for at least 200 Martian days. “It appears they are going to be with us for quite some time,” she said.