生命迹象

Did the samples gathered by the Viking landers of the 1970s actually find life on Mars? Paul Marks is glued to an expert rethink Chryse Planitia, the plains of gold, snapped by the Viking 1 lander in 1977 Book Meet the Neighbors Steven A. Benner Allen Lane FIFTY years ago last month, a life-detection test developed by Gil Levin, a NASA investigator and an engineer schooled in sensing dangerous microbial colonies in sewage, landed on Mars. It was on board Viking 1, the first of two life- seeking landers. Amazingly, both of the landers succeeded straight away. Levin’s test, alongside two others, quickly gave what planetary scientists call strong “life affirmative” results. …