Mars special: Celebrating a year of exploration New Scientist

IN SPACE, a year can be a long time. Back at the beginning of 2004, the idea that the Red Planet had once been covered with rivers, lakes and seas was just a theory. Now abundant evidence on the ground has turned it into established fact. A year ago it was scientific heresy even to talk of the possibility of life existing today on Mars. But with the proof of past water, plus evidence that there was methane in the air not so long ago, it is now a subject for serious discussion.