On March 21, 1971, United Nations Secretary-General U Thant spoke of a spaceship Earth on Earth Day, hereby referring to the ecosystem services the earth supplies to us, and hence our obligation to protect it (and with it, ourselves).
1971年3月21日，联合国秘书长吴丹在地球日上提到了太空船地球号，指的是地球生态系统服务对人们的恩典，人们又义务保护它（就是保护自己）。