This series of five maps shows near-global coverage of key minerals that help plot the history of Mars.
The map of hydrated minerals indicates individual sites where a range of minerals that form only in the presence of water were detected. The maps of olivine and pyroxene tell the story of volcanism and the evolution of the planet’s interior. Ferric oxides, a mineral phase of iron, are present everywhere on the planet: within the bulk crust, lava outflows and the dust oxidised by chemical reactions with the martian atmosphere, causing the surface to ‘rust’ slowly over billions of years, giving Mars its distinctive red hue.
The apparent data gap over the Hellas Basin, towards the lower right, is due to the unique atmospheric conditions in this 9 km-deep impact crater preventing robust detections from the crater floor to be made by OMEGA. The vast distance between the surface to Mars Express also impairs measurements over the smaller Argyre basin just to the left of centre in the southern hemisphere. Seasonal carbon dioxide and water-ice frosts occurring in the polar regions restricts observing periods and spatial coverage in these regions.