Life may have had a tough time getting started in the ancient environment that left its mark in the Martian rock layers examined by NASA's Opportunity rover. Conditions in the Meridiani Planum region of Mars were strongly acidic, oxidizing, and sometimes wet.

While most planetary scientists believe water on Mars is the best clue to finding interesting rock samples, there are big questions that remain about where exactly that water may be found. New results give a short-list for some who track the water history on the red planet.

With the second rover less than two weeks from a rendezvous on the other side of Mars from the current Spirit rover, comparisons between landing sites and entry conditions take on increased importance.

The three standout features in the initial color postcard from the Opportunity landing site at Meridiani Planum include: the first observed martian bedrock, a talcum-powder-like soil texture, and the iron-rich color reminiscent of red clays from Texas and Oklahoma.

by Astrobiology Magazine staffwriter As the Spirit rover unfolded from its stowed position and prepared to drive with six wheels in the martian soil, mission scientists described why the current landing site has their team ready to drive.Astrobio Magazine -- "We asked the rover engineers to fit a square peg in a round hole," said the Spirit rover mission manager, Jennifer Trosper of NASA JPL.