Mars Orbiter Focusing on Fellow Probes

Jan. 24, 2007 — With the prospect that liquid water exists on Mars, that biologically produced methane may be in the atmosphere and other mind-bending Martian mysteries, scientists were surprisingly united about the first targets for NASA's new $500 million Mars Reconnaissance Orbiter: our old stuff.

And they've been successful, too, coming up with a picture book full of dead — and living — probes. There are the Viking landers from the 1970s, the 1997 Mars Pathfinder mother ship, which marked NASA's return to the Red Planet after a 20-year hiatus, and the long-running rovers, Spirit and Opportunity, now in their third year of operation.

"This instrument is just blowing us all away," said Rob Manning, chief engineer for NASA's Mars program at the Jet Propulsion Laboratory in Pasadena, Calif. "Until I actually saw the pictures, I didn't really grasp what MRO was able to do."

Scientists say they are not being vain.

Imaging known objects makes it easier to interpret the size of other topographical features on the planet's surface. And one of MRO's main tasks is to find a safe landing spot for a new rover named Phoenix, which is scheduled to be launched in August to explore the northern polar region of Mars.

With its high-resolution camera, MRO can image details on the planet's surface as small as about 2.6 feet (0.8 meters) across. By comparing the orbital views of old probes' landing sites with photos on the ground by the probes themselves, scientists have been able to estimate the number and size of smaller boulders that MRO can't see.

"It aids our interpretation of orbital images of other places," said Alfred McEwen, with the University of Arizona in Tucson and the principal investigator for MRO's high fidelity camera.

The pictures already have forced Phoenix mission planners to scrap their first-choice landing spot.

"We found boulders the size of VW Bugs," Manning said in an interview with Discovery News. "Even if we landed there safely, we wouldn't be able to open the solar arrays because you'd bang into a boulder. So we have to bail out on our No. 1 science site."

MRO's family album not only includes the Mars Pathfinder, but also the parachutes, airbags, pieces of the heat shield and other gear the spacecraft used to descend and land on the planet's surface. The team is still on the hunt for Pathfinder's small rover, Sojourner.

"This is so cool," Manning said. "We had a mental picture of where things were on Mars, but we couldn't see them. It's a lot of fun to see our hand-made equipment on Mars."