Mars' South Pole Is Totally Alien... Obviously.

When you think of Mars you'd be forgiven if the first words that pop into your head are 'Red Planet', or 'Chocolate Bar'.

The fact is that the planet Mars is neither all red or indeed made of delicious chocolate and caramel. It's a glorious concoction of colours that range from dark browns to deep reds, right through to a clear cream coloured.

This is Mars' South Pole. Taken by the ESA spacecraft Mars Express it shows the huge ice cap that dominates the southern most tip of the planet.

Composed of water and carbon dioxide the cap isn't a perfect circle and there's a reason for that. A particularly massive crater formation called Hellespontus Montes is driving Martian winds down against the cap, forcing it into that somewhat slanted disc shape.

At around 3km thick and spanning over 350km in diameter it's hard to imagine the sheer size of such an enormous body of ice.