The atmosphere was stripped away by solar winds, Mars lost its magnetosphere, and then cosmic rays and U.V. bombarded the surface and water escaped to space and went underground.
大气被太阳风一揭而散， 火星失去了它的磁层， 接着宇宙射线和紫外线冲击了地表 然后水资源逃离到了空间中和地层下。