Ben Bova 
Mars [EPUB ebook] 

To the harsh landscape of Sol’s fourth planet travel thirteen astronauts, the best scientists from eleven nations, on a history-making voyage into the unknown. The international crew of the Mars mission have spent nine months in space, crossing 100 million kilometres, to reach the last great frontier. Their voyage is fraught with disputes, both personal and political, and their time on Mars limited to 'footprints and flags’; yet while there they will come face-to-face with the most incredible and shocking discovery of all.