Colour mosaic of Mars’ North Pole
Colour mosaic of Mars’ North Pole
With its icy ‘spiral arms’, curved like hooks, Mars’ ice cap looks very different than the polar ice caps on Earth. The alternate layers of ice and dust are likely to have originated from winds that carry dust and deposit it in a seasonal rhythm. The permanent ice cap has a diameter of approximately 1100 kilometres and is over two kilometres thick in places. The ice cap consists of a mixture of water ice and frozen carbon dioxide. The entire mass is comparable with that of the Greenland ice sheet. Almost no impact craters can be seen, which suggests that the polar cap in this form is not very old.
