by James Burk
MarsNews.com

The Mars Exploration Rover team was astonished at the landscape found when Opportunity landed yesterday within a 20-meter crater, somewhere on Meridiani Planum. The region of mars was chosen due to its abundance of hematite, a mineral usually formed in long-standing bodies of liquid water.

"I am flabbergasted. I am astonished. I am blown away,” said Steven Squyres, the MER mission’s Principal Investigator. “I still don't know what we're looking at.”

Around four hours after landing, JPL began receiving the first images from the Opportunity rover, showing the flat, nearly featureless terrain. Other than the marks created by the airbags’ retraction, the major feature of the landing site is the first bedrock outcropping ever seen on Mars.

The bedrock is geologically important because “you know where it came from,” according to Squyres. All other landing sites have been littered with rocks whose origin is ambiguous. The outcropping will be an early target when the rover traverses off the lander.

Previous landing sites look much different than Opportunity’s. Both Viking landers found rocky, desert-like plains upon landing. Mars Pathfinder was targeted at Ares Vallis, predicted to be an outflow channel where many rocks were deposited by catastrophic flooding. Spirit’s landing site, Gusev crater, resembles the Viking landing sites more than Pathfinder’s, with a limited amount of rocks, hopefully making it easier for the rover to traverse.

Early indications are that Opportunity landed in a crater, a “300 million mile hole in one” as Dr. Squyres put it. While the team is not 100% sure, the crater is approximately 20 meters wide and a couple meters deep. It should not pose any problems when the rover attempts to traverse out of it.

A much larger crater, seen on the descent images today, lies around half a mile away, and will likely be a longer-term target of the mission.

Opportunity is only the fifth successful landing on Mars since attempts first began in 1971. The first successful lander was Viking 1 in 1975, soon followed by its twin Viking 2. Mars Pathfinder in 1997 was the last successful Mars lander, prior to Spirit’s touch-down on January 3rd, 2004. All successful Mars landings have been attempted by the United States. The Soviet Union (with Mars 2 & 3 in 1971 and Mars ’96 in 1996) and now the European Space Agency (with the Beagle 2) have both experienced landing failures.

Posted by jburk at January 25, 2004 12:00 PM | TrackBack