] 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.[44] Its red colour comes from iron oxide
                            (rust) in its soil.[45] Mars has two tiny natural satellites (Deimos and Phobos) thought to
                            be captured asteroids.[46]
                        </description>
 