... 4000 Kilometers Above Saturns Iapetus . ... What does the surface of Saturn's mysterious moon Iapetus look like? To help find out, the robotic Cassini spacecraft now orbiting Saturn was sent soaring last week just 2,000 kilometers from the unique equatorial ridge of the unusual walnut-shaped two-toned moon. ... Inside Victoria Crater on Mars . ... At about 100 meters from the cargo bay of the space shuttle Challenger, Bruce McCandless II was further out than anyone had ever been before. ...