Or, as NASA contends, it may take longer: The space agency puts the date in the 2030s, and then not to land on Mars but just to orbit it. At National Geographic, exploration of new frontiers is in ...

It was not the Mars of the Viking missions of the 1970s or even of the last successful landing mission a few years ago. And although he had spent many of his 34 years honing his own sense of the ...