The NASA team had hoped Spirit would find equally clear signs on the ground: things like the sort of rounded pebbles or boulders found in terrestrial river beds, ripples in the sand, or rocks built up over time by the deposit of sediments from water.

• nasa的工作人员希望“勇气号”能在地面上找到对等的痕迹，如：河床上的圆形鹅卵石或漂石，沙滩上的波纹，经过长时间由水中沉淀物沉积而成的石头。