1.   Altering Martian soil to support plants from Earth may be a solution.

2.   Commanded from Earth to traverse a three-foot stretch of Martian soil, Sojourner went a little more than five inches too far.

3.   On the way, little Sojourner was ordered to lock five of its six wheels and spin one to dig beneath the surface of the Martian soil.

4.   Of particular concern, McSween said, is the question of toxic metals in Martian soil and windblown dust.

5.   On board is Sojourner, a rover the size of a shoe box that is roaming around gathering data on Martian soil.

6.   Samples that the landers took of the Martian soil underwent a battery of tests but showed no unambiguous signs of life.

7.   Temperature sensors will tell how well the Martian soil conducts heat, giving clues to its composition.

8.   The calcium and sulfur in Martian soil are in the form of gypsum, the stuff of plaster.

9.   The fact-finding mission will study the composition of Martian soils and test the engineering of a descent system that uses parachutes and large balloons to soften surface landings.

10.   The images should reveal whether its passenger, Sojourner, arrived intact and has an unobstructed path to the Martian soil.