火星模拟计划It takes about nine months to travel from Earth to Mars. If astronauts (宇航员) can get there, then they could live and work on Mars. But it’s a big challenge for astronauts.
21世纪报社版权所有，未经书面授权，禁止转载或建立镜像。 主办单位：中国日报社 Copyright by 21st Century English Education Media All Rights Reserved 版权所有 复制必究 京ICP备13028878号-12京公网安备 11010502033664号
京公网安备 11010502033664号
