在国际空间站生活了近1年时间的美国宇航局宇航员斯科特·凯利与两名同伴搭乘“联盟号”飞船返回地球。现在,斯科特·凯利回到了自己的家中,但是他的新一项任务才刚刚开始,因为他在太空中近一年的生活也是美国宇宙局研究计划的一部分。在这一年中,他的双胞胎兄弟马克·凯利则生活在地球上。科学家希望通过对他们兄弟两人的身体变化情况进行对比分析,研究太空旅行对人体 NASA astronaut Scott Kelly, who has been on the International Space Station for nearly a year, returns to Earth with two of his companions on the Soyuz spacecraft. Now, Scott Kelly is back in his home, but his new assignment has just begun, as his nearly one-year life in space is also part of NASA’s research program. During the year, his twin brother, Mark Kelly, lives on Earth. Scientists hope to compare the body changes of their two brothers and study the impact of space travel on the human body