Wallpaper: Iapetus Portrait

Wallpaper: Iapetus Portrait Iapetus is a moon that is on one side one of the brightest objects and on the other one of the darkest objects. In addition to this oddity is the giant equatorial ridge that runs nearly complete around the whole of the moon. Neither of these features origins have been established, although many theories exist. One theory is that Iapetus at one time grazed the edge of Saturn’s rings which would have deposited a huge amount of material around its equator. But to do this it would have had to have been much closer to Saturn and have been ejected out past most of the larger moons to its present position. Another theory suggests that the materials might have come from another of Saturn’s moons, Pheobe, and spiraled in to be swept up by Iapetus. More theories involve internal heating and the movement of matrials from the interior to the surface through various means such as cryo-volcanism.

IMAGE NOTE: The image was originally black and white and has been colorized based upon other colored images.

Also see the wallpaper of Iapetus’s brighter side here added in September, 2007.