白天,当你头顶蓝天白云;晚上,当你仰望璀璨星空,你一定会感叹,我们头顶的这片天,是多么洁净呀,不像我们生活的地面上,垃圾随处可见。这种想法嘛,在几十年前还是正确的,可是现在呀,那看似洁净的太空,其实也布满了垃圾。自上世纪50年代开始进军宇宙以来,人类已经发射了四千多枚 During the day, when you have blue sky and white clouds above you, when you look up to the bright stars and sky at night, you will surely lament how clean it is on the sky above our head. Unlike the ground on which we live, rubbish can be seen everywhere. Well, this idea was still correct in the past few decades, but now it appears that the seemingly clean space is in fact covered with rubbish. Since the beginning of entering the universe in the 1950s, more than 4,000 human beings have been launched