All of Creation
Mars
Mars (1.5 AU from the Sun) is smaller than Earth and Venus (0.107 Earth masses). It possesses an atmosphere of mostly carbon dioxide with a surface pressure of 6.1 millibars (roughly 0.6% of that of Earth).[76] Its surface, peppered with vast volcanoes, such as Olympus Mons, and rift valleys, such as Valles Marineris, shows geological activity that may have persisted until as recently as 2 million years ago.[77] Its red colour comes from iron oxide (rust) in its soil.[78] Mars has two tiny natural satellites (Deimos and Phobos) thought to be captured asteroids.[79]