MARINER 9
he novel feature of NASA’s Mariner 9 probe was a rocket engine powerful enough to place it in a stable orbit, allowing it to observe the planet at leisure. The previous successful Mars missions – Mariners 4, 6 and 7 – had only involved fleeting flybys, collecting a meagre 222 images between them. Mariner 9’s main objective was to photograph a large proportion of the
