美国送到火星上的两辆火星漫游车,勇气号和机遇号,现在已经在火星表面活动了两年的时间。它们分别穿越了几公里的路程,在行进途中,它们还要频繁地停下来,用它们的照相机、分光计和其他设备寻找火星远古时期曾含有液态水的证据。它们的努力取得了成效,基本证明了火星上曾经存在 Two Mars rover, courage and Opportunity aircraft that the United States has sent to Mars have now been active on Mars for two years. They traveled several kilometers respectively, and on their way, they stopped frequently, using their cameras, spectrometers and other devices to find evidence that Mars had contained liquid water in ancient times. Their efforts have yielded results, basically demonstrating the existence on Mars