Oxidized iron dominates the Martian color palette. The dusty reds, ochers, browns and tans give the planet its nickname: the Red Planet. But new images of Mars’ south polar region show something different. Swirls of pink, purple and red highlight the region and a feature named Thyles Rupes, an icy crag with cliffs higher than 1 km (0.6 miles). Rupes means cliff in Latin, while Thyles is a mythical northern land spoken of in the ancient world.
All the differently colored materials in this region have different sources. Volcanoes created and spread the darker material, which is rich in minerals like olivine and pyroxene, both of which are also plentiful in Earth’s mantle. Olivine is made of magnesium, iron and silicate. Pyroxenes are a group of silicate minerals made mostly of silicon and oxygen, also common in Earth’s upper mantle.
The pale bluish areas, like those in the crater, are covered in frozen carbon dioxide. Near the south pole, this material persists even in springtime, when this image was captured. The pale patch on the lower left is part of the south polar cap. The main cap never melts, but a seasonal CO2 frost cap expands and contracts with the seasons.
