There’s a huge amount still to find out about Mars. Despite its more-or-less uniform colour, Mars is a hugely diverse world, with a variety of different environments and landscape features -we really have only scratched the surface, but as we do so, we are discovering evidence for an increasingly Earth-like past, raising major questions that we still can’t fully answer.
How much water flowed on the surface? Did Mars ever have seas? What happened to its atmosphere and oceans? Did simple life ever manage to get a foothold and might it still cling on somewhere? These are mysteries that recent craft like MAVEN and MOM are hoping to solve.